Disentangling the effect of growth from development in size-related trait scaling relationships

In plant ecology, the terms growth and development are often used interchangeably. Yet these constitute two distinct processes. Plant architectural traits (e.g. number of successive forks) can estimate development stages. Here, we show the importance of including the effect of development stages to better understand size-related trait scaling relationships (i.e. between height and stem diameter). We focused on one common savanna woody species (Senegalia nigrescens) from the Greater Kruger Area, South Africa. We sampled 406 individuals that experience different exposure to herbivory, from which we collected four traits: plant height, basal stem diameter, number of successive forks (proxy for development stage), and resprouting. We analysed trait relationships (using standardized major axis regression) between height and stem diameter, accounting for the effect of ontogeny, exposure to herbivory, and resprouting. The number of successive forks affects the scaling relationship between height and stem diameter, with the slope and strength of the relationship declining in more developed individuals. Herbivory exposure and resprouting do not affect the overall height-diameter relationship. However, when height and stem diameter were regressed separately against number of successive forks, herbivory exposure and resprouting had an effect. For example, resprouting individuals allocate more biomass to both primary and secondary growth than non-resprouting plants in more disturbed conditions. We stress the need to include traits related to ontogeny so as to disentangle the effect of biomass allocation to primary and secondary growth from that of development in plant functional relationships.

Conflation of reforestation with restoration is widespread

Across Africa, vast areas of nonforest are threatened by inappropriate restoration in the form of tree planting.

The bii4africa dataset of faunal and floral population intactness estimates across Africa's major land uses

Sub-Saharan Africa is under-represented in global biodiversity datasets, particularly regarding the impact of land use on species' population abundances. Drawing on recent advances in expert elicitation to ensure data consistency, 200 experts were convened using a modified-Delphi process to estimate 'intactness scores': the remaining proportion of an 'intact' reference population of a species group in a particular land use, on a scale from 0 (no remaining individuals) to 1 (same abundance as the reference) and, in rare cases, to 2 (populations that thrive in human-modified landscapes). The resulting bii4africa dataset contains intactness scores representing terrestrial vertebrates (tetrapods: ±5,400 amphibians, reptiles, birds, mammals) and vascular plants (±45,000 forbs, graminoids, trees, shrubs) in sub-Saharan Africa across the region's major land uses (urban, cropland, rangeland, plantation, protected, etc.) and intensities (e.g., large-scale vs smallholder cropland). This dataset was co-produced as part of the Biodiversity Intactness Index for Africa Project. Additional uses include assessing ecosystem condition; rectifying geographic/taxonomic biases in global biodiversity indicators and maps; and informing the Red List of Ecosystems.

A trillion trees: carbon capture or fuelling fires?

Afforesting grassy systems for carbon gain using flammable plantation trees could shift the fire regime from lower intensity grass-fuelled fires to high-intensity crown fires. Future changes in climate will worsen this. We highlight the fire risk of trees planted for carbon and costs of fire protection using African examples.

Valuing the functionality of tropical ecosystems beyond carbon

Land-based carbon sequestration projects, such as tree planting, are a prominent strategy to offset carbon emissions. However, we risk reducing natural ecosystems to one metric - carbon. Emphasis on restoring ecosystems to balance ecosystem services, biodiversity conservation, and carbon sequestration is a more appropriate strategy to protect their functioning.

Steal the rain: Interception loses and rainfall partitioning by a broad-leaf and a fine-leaf woody encroaching species in a southern African semi-arid savanna

Woody plant encroachment (WPE) has been found to alter ecosystem functioning and services in savannas. In rain-limited savannas, increasing woody cover can reduce streamflow and groundwater by altering evapotranspiration rates and rainfall partitioning, but the ecological relevance of this impact is not well known. This study quantified the altered partitioning of rainfall by two woody plant structural types (fine- and broad-leaved trees) across a gradient of encroachment in a semi-arid savanna in South Africa. Averaged across both plant functional types, loss of rainfall through canopy interception and subsequent evaporation roughly doubled (from 20.5% to 43.6% of total rainfall) with a roughly 13-fold increase in woody cover (from 2.4 to 31.4 m²/ha tree basal cover). Spatial partitioning changes comprised fourfold increases in stemflow (from 0.8% to 3.9% of total rainfall) and a decline in throughfall proportion of about two-fifths (from 80.2% to 47.3% of total rainfall). Changes in partitioning were dependent on plant functional type; rainfall interception by the fine-leaved multi-stemmed shrub Dichrostachys cinerea was almost double that of the broad-leaved tree Terminalia sericea at the highest levels of woody encroachment (i.e., 49.7% vs. 29.1% of total rainfall intercepted at tree basal area of 31.4 m²/ha). Partitioning was also dependent on rainfall characteristics, with the proportion of rainfall intercepted inversely related to rainfall event size and intensity. Therefore, increasing tree cover in African grassy ecosystems reduces the amount of canopy throughfall, especially beneath canopies of fine-leaved species in smaller rainfall events. Rainfall interception traits may thus confer a selective advantage, especially for fine-leaved woody plant species in semi-arid savannas.

[Population Health Intervention Research, Health Technology Assessment, Health Services Research and Intervention Implementation Research : Convergences and Singularities]

In public health, intervention is an object of research and evaluation which, over time, has given rise to numerous approaches. The first part of the article proposes to reposition intervention research in population health and intervention evaluation on a continuum. Although the former has a more cognitive objective and the latter a more pragmatic objective, they are not mutually exclusive. The distinction between these two practices is based on the predominance of the following characteristics: the objectives pursued, the scope of the investigations, the regulatory constraints, the financing obtained, the ethical approaches taken, and the deliverables established. The second part of the article offers a glance different fields and approaches within the continuum between these two poles: Health Technology Assessment, Health Services Research and Implementation Research. While all of them have the study of health interventions at their core, but each has developed through specialisation in one or the other type of intervention, in a particular scope or context, in certain evaluation questions, or in specific approaches. all as gateways to the study of public health intervention, these different approaches are by no means mutually exclusive.

[Describing and disseminating organizational innovation in public health DINOSP ; guide (Description of Organizational Innovations in Public Health)]

OBJECTIVES

The transition from experimentation to the scaling up of organizational innovations in public health is arduous. The innovation process requires back-up in view of enhancing the chances of success and generalization. The aim of this article is to present the development of a guide to support the description and analysis of organizational innovations in public health.

METHOD

The mobilization of two analysis and description tools, ASTAIRE and TIDIeR, made it possible to select the innovation criteria to be considered for generalization. Collective discussions between actors, decision-makers and researchers and individual interviews with the latter refined and completed the proposed guide, which was reread by experts and tested by project leaders, thereby improving its accuracy and usability.

RESULTS

The guide puts forward a two-step approach: i) to describe innovation at two levels: on the one hand, intervention methods, and on the other hand, interventional, population or contextual components corresponding to 27 criteria and ii) to assess the transferability of the innovation by distinguishing its key functions, its formal elements and the margins of maneuver to be maintained.

DISCUSSION

The guide presents a modular vision of innovations and leaves room for reflection on its mechanisms. It favors the synchronization of innovations with the existing system and their mutualization.

CONCLUSIONS

By putting forward a standardised description of organizational innovations in health and analyzing their effectiveness, the tool can effectively contribute to the development of effective, adaptable and generalizable projects, and thereby contribute to progress in public health.

Stepped-wedge randomized controlled trial of laparoscopic ventral mesh rectopexy in adults with chronic constipation

Background

The effectiveness of laparoscopic ventral mesh rectopexy (LVMR) in patients with defecatory disorders secondary to internal rectal prolapse is poorly evidenced. A UK-based multicenter randomized controlled trial was designed to determine the clinical efficacy of LVMR compared to controls at medium-term follow-up.

Methods

The randomized controlled trial was conducted from March 1, 2015 TO January 31, 2019. A stepped-wedge RCT design permitted observer-masked data comparisons between patients awaiting LVMR (controls) with those who had undergone surgery. Adult participants with radiologically confirmed IRP refractory to conservative treatment were randomized to three arms with different delays before surgery. Efficacy outcome data were collected at equally stepped time points (12, 24, 36, 48, 60, and 72 weeks). Clinical efficacy of LVMR compared to controls was defined as ≥ 1.0-point reduction in Patient Assessment of Constipation-Quality of Life and/or Symptoms (PAC-QOL and/or PAC-SYM) scores at 24 weeks. Secondary outcome measures included 14-day diary data, the Generalized Anxiety Disorder scale (GAD-7), the Patient Health Questionnaire-9 (PHQ-9), St Marks incontinence score, the Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire (PISQ-12), the chronic constipation Behavioral Response to Illness Questionnaire (CC-BRQ), and the Brief Illness Perception Questionnaire (BIPQ).

Results

Of a calculated sample size of 114, only 28 patients (100% female) were randomized from 6 institutions (due mainly to national pause on mesh-related surgery). Nine were assigned to the T0 arm, 10 to T12, and 9 to T24. There were no substantial differences in baseline characteristics between the three arms. Compared to baseline, significant reduction (improvement) in PAC-QOL and PAC-SYM scores were observed at 24 weeks post-surgery (– 1.09 [95% CI – 1.76, – 0.41], p = 0.0019, and – 0.92 [– 1.52, – 0.32], p = 0.0029, respectively) in the 19 patients available for analysis (9 were excluded for dropout [n = 2] or missing primary outcome [n = 7]). There was a clinically significant long-term reduction in PAC-QOL scores (− 1.38 [− 2.94, 0.19], p = 0.0840 at 72 weeks). Statistically significant improvements in PAC-SYM scores persisted to 72 weeks (− 1.51 [− 2.87, − 0.16], p = 0.0289). Compared to baseline, no differences were found in secondary outcomes, except for significant improvements at 24 and 48 weeks on CC-BRQ avoidance behavior (− 14.3 [95% CI − 23.3, − 5.4], and − 0.92 [− 1.52, − 0.32], respectively), CC-BRQ safety behavior (− 13.7 [95% CI − 20.5, − 7.0], and − 13.0 [− 19.8, − 6.1], respectively), and BIPQ negative perceptions (− 16.3 [95% CI − 23.5, − 9.0], and − 10.5 [− 17.9, − 3.2], respectively).

Conclusions

With the caveat of under-powering due to poor recruitment, the study presents the first randomized trial evidence of short-term benefit of LVMR for internal rectal prolapse.

Trial registration

ISRCTN Registry (ISRCTN11747152).

Supplementary Information

The online version contains supplementary material available at 10.1007/s10151-022-02633-w.

Savanna Rodents’ Selective Removal of an Encroaching Plant’s Seeds Increased With Grass Biomass

In savannas across the planet, encroaching woody plants are altering ecosystem functions and reshaping communities. Seed predation by rodents may serve to slow the encroachment of woody plants in grasslands and savannas. Our goals for this study were to determine if rodents in an African savanna selectively removed seeds of an encroaching plant and if foraging activity was influenced by the local vegetation structure or by the landscape context. From trials with two species of seeds (encroacher = Dichrostachys cinerea, non-encroaching overstory tree = Senegalia nigrescens) at 64 seed stations, we recorded 1,065 foraging events by seven species of granivorous rodents. We found a strong positive relationship between rodent activity and the number of seeds removed during trials. Foraging events were dominated by rodent seed predators, with <10.6% of events involving a rodent with the potential for secondary dispersal. Rodents selectively removed the seeds of the encroaching species, removing 32.6% more D. cinerea seeds compared to S. nigrescens. Additionally, rodent activity and the number of seeds removed increased at sites with more grass biomass. Our results suggest a potential mechanistic role for rodents in mitigating the spread of woody plants in grass dominated savannas.

[Innovative transformation of the health system through a preventive transition]

Given today's evolution of the healthcare system, organizational transformations, technological developments and major challenges, innovation has taken on primordial importance. In this context and with considerable support, many experimentations have taken place. Unfortunately, few have managed to scale up. What results is a congeries of innovations without a future, possibly avoidable squandering of resources, a number of missed opportunities, and the grim prospect of inventor burnout. As regards prevention, innovation is at the heart of an anticipated "preventive transition" of the health system that has yet to achieve operational status. In this article we attempt to redesign the contours of innovation in health, considering it first and foremost in regard to its social utility. We will go on to explore the limitations of innovative practices that delay the arrival of advances in health. Four types of obstacles appear: faulty evaluation; insufficient dialogue between researchers, stakeholders and decision-makers; lack of visibility and, finally, conceptions and perceptions of innovation characterized by tunnel vision. In the concluding section of this paper, we will present several tracks through which the innovation process could be impelled to drive health system transformation. They consist in: (i) incorporating an evaluative and comprehensive research into innovation processes, (ii) elaborating "bottom-up" approaches giving special consideration to innovations instigated by stakeholders and brought to fruition under real-life conditions, (iii) breaking from standardization by thinking from the outset of the adaptability of innovations and, finally, (iv) tying in the experimental approach with a decision-making process.

What shapes the range edge of a dominant African savanna tree, Colophospermum mopane? A demographic approach

Climate is widely assumed to be the primary process that limits the distribution ranges of plants. Yet, savannas have vegetation not at equilibrium with climate, instead its structure and function are shaped by interactions between fire, herbivory, climate, and vegetation. I use the rich literature of a dominant African savanna woody plant, Colophospermum mopane, to demonstrate that climate and disturbance interact with each demographic stage to shape this species range limits. This synthesis highlights that climate-based predictions for the range of C. mopane inadequately represents the processes that shape its distribution. Instead, seed bank depletion and rainfall limitation create a demographic bottleneck at the early seedling stage. The legacy of top-kill from disturbance changes tree stand architecture causing a critical limitation in seed supply. Exposure to top-kill at all demographic stages causes a vigorous resprouting response and shifts tree architecture from that of 1-2 stemmed tall trees to that of a short multi-stemmed shrub. The shorter, multi-stemmed shrubs are below the height threshold (4 m) at which they can produce seeds, resulting in shrub-dominated landscapes that are effectively sterile. This effect is likely most pronounced at the range edge where top-kill-inducing disturbances increase in frequency. The proposed mechanistic, demographic-based understanding of C. mopane's range limits highlights the complexity of processes that interact to shape its range edges. This insight serves as a conceptual model for understanding the determinants of range limits of other dominant woody savannas species living in disturbance limited ecosystems.

Evaluation of PSA and PSA Density in a Multiparametric Magnetic Resonance Imaging-Directed Diagnostic Pathway for Suspected Prostate Cancer: The INNOVATE Trial

Objectives: To assess the clinical outcomes of mpMRI before biopsy and evaluate the space remaining for novel biomarkers. Methods: The INNOVATE study was set up to evaluate the validity of novel fluidic biomarkers in men with suspected prostate cancer who undergo pre-biopsy mpMRI. We report the characteristics of this clinical cohort, the distribution of clinical serum biomarkers, PSA and PSA density (PSAD), and compare the mpMRI Likert scoring system to the Prostate Imaging-Reporting and Data System v2.1 (PI-RADS) in men undergoing biopsy. Results: 340 men underwent mpMRI to evaluate suspected prostate cancer. 193/340 (57%) men had subsequent MRI-targeted prostate biopsy. Clinically significant prostate cancer (csigPCa), i.e., overall Gleason ≥ 3 + 4 of any length OR maximum cancer core length (MCCL) ≥4 mm of any grade including any 3 + 3, was found in 96/195 (49%) of biopsied patients. Median PSA (and PSAD) was 4.7 (0.20), 8.0 (0.17), and 9.7 (0.31) ng/mL (ng/mL/mL) in mpMRI scored Likert 3,4,5 respectively for men with csigPCa on biopsy. The space for novel biomarkers was shown to be within the group of men with mpMRI scored Likert3 (178/340) and 4 (70/350), in whom an additional of 40% (70/178) men with mpMRI-scored Likert3, and 37% (26/70) Likert4 could have been spared biopsy. PSAD is already considered clinically in this cohort to risk stratify patients for biopsy, despite this 67% (55/82) of men with mpMRI-scored Likert3, and 55% (36/65) Likert4, who underwent prostate biopsy had a PSAD below a clinical threshold of 0.15 (or 0.12 for men aged <50 years). Different thresholds of PSA and PSAD were assessed in mpMRI-scored Likert4 to predict csigPCa on biopsy, to achieve false negative levels of ≤5% the proportion of patients whom who test as above the threshold were unsuitably high at 86 and 92% of patients for PSAD and PSA respectively. When PSA was re tested in a sub cohort of men repeated PSAD showed its poor reproducibility with 43% (41/95) of patients being reclassified. After PI-RADS rescoring of the biopsied lesions, 66% (54/82) of the Likert3 lesions received a different PI-RADS score. Conclusions: The addition of simple biochemical and radiological markers (Likert and PSAD) facilitate the streamlining of the mpMRI-diagnostic pathway for suspected prostate cancer but there remains scope for improvement, in the introduction of novel biomarkers for risk assessment in Likert3 and 4 patients, future application of novel biomarkers tested in a Likert cohort would also require re-optimization around Likert3/PI-RADS2, as well as reproducibility testing.

Measuring the success of climate change adaptation and mitigation in terrestrial ecosystems

Natural and seminatural ecosystems must be at the forefront of efforts to mitigate and adapt to climate change. In the urgency of current circumstances, ecosystem restoration represents a range of available, efficient, and effective solutions to cut net greenhouse gas emissions and adapt to climate change. Although mitigation success can be measured by monitoring changing fluxes of greenhouse gases, adaptation is more complicated to measure, and reductions in a wide range of risks for biodiversity and people must be evaluated. Progress has been made in the monitoring and evaluation of adaptation and mitigation measures, but more emphasis on testing the effectiveness of proposed strategies is necessary. It is essential to take an integrated view of mitigation, adaptation, biodiversity, and the needs of people, to realize potential synergies and avoid conflict between different objectives.

Comment on "The global tree restoration potential"

Bastin et al's estimate (Reports, 5 July 2019, p. 76) that tree planting for climate change mitigation could sequester 205 gigatonnes of carbon is approximately five times too large. Their analysis inflated soil organic carbon gains, failed to safeguard against warming from trees at high latitudes and elevations, and considered afforestation of savannas, grasslands, and shrublands to be restoration.

Human impacts in African savannas are mediated by plant functional traits

Tropical savannas have a ground cover dominated by C₄ grasses, with fire and herbivory constraining woody cover below a rainfall-based potential. The savanna biome covers 50% of the African continent, encompassing diverse ecosystems that include densely wooded Miombo woodlands and Serengeti grasslands with scattered trees. African savannas provide water, grazing and browsing, food and fuel for tens of millions of people, and have a unique biodiversity that supports wildlife tourism. However, human impacts are causing widespread and accelerating degradation of savannas. The primary threats are land cover-change and transformation, landscape fragmentation that disrupts herbivore communities and fire regimes, climate change and rising atmospheric CO₂ . The interactions among these threats are poorly understood, with unknown consequences for ecosystem health and human livelihoods. We argue that the unique combinations of plant functional traits characterizing the major floristic assemblages of African savannas make them differentially susceptible and resilient to anthropogenic drivers of ecosystem change. Research must address how this functional diversity among African savannas differentially influences their vulnerability to global change and elucidate the mechanisms responsible. This knowledge will permit appropriate management strategies to be developed to maintain ecosystem integrity, biodiversity and livelihoods.

Woody encroachment over 70 years in South African savannahs: overgrazing, global change or extinction aftershock?

Woody encroachment in 'open' biomes like grasslands and savannahs is occurring globally. Both local and global drivers, including elevated CO2, have been implicated in these increases. The relative importance of different processes is unresolved as there are few multi-site, multi-land-use evaluations of woody plant encroachment. We measured 70 years of woody cover changes over a 1020 km(2) area covering four land uses (commercial ranching, conservation with elephants, conservation without elephants and communal rangelands) across a rainfall gradient in South African savannahs. Different directions of woody cover change would be expected for each different land use, unless a global factor is causing the increases. Woody cover change was measured between 1940 and 2010 using the aerial photo record. Detection of woody cover from each aerial photograph was automated using eCognitions' Object-based image analysis (OBIA). Woody cover doubled in all land uses across the rainfall gradient, except in conservation areas with elephants in low-rainfall savannahs. Woody cover in 2010 in low-rainfall savannahs frequently exceeded the maximum woody cover threshold predicted for African savannahs. The results indicate that a global factor, of which elevated CO2 is the likely candidate, may be driving encroachment. Elephants in low-rainfall savannahs prevent encroachment and localized megafaunal extinction is a probable additional cause of encroachment.This article is part of the themed issue 'Tropical grassy biomes: linking ecology, human use and conservation'.

Surgery for constipation: systematic review and clinical guidance: Paper 1: Introduction & Methods

AIM

This manuscript provides the introduction and detailed methodology used in subsequent reviews to assess the outcomes of surgical interventions with the primary intent of treating chronic constipation in adults and to develop recommendations for practice.

METHOD

PRISMA guidance was adhered to throughout. A literature search was performed in public databases between January 1960 and February 2016. Studies that fulfilled strictly-defined PICOS (patients, interventions, controls, outcome, and study design) criteria were included. The process involved two groups of participants: (i): 'a clinical guidance group' of 18 UK experts (including junior support) who performed the systematic reviews and produced summary evidence statements (SES) based strictly on data synthesis in each review. The same group then produced prototype graded practice recommendations (GPRs) based on coalescence of SES and expert opinion; (ii): a European Consensus group of 18 ESCP (European Society of Coloproctology) nominated experts from nine European countries evaluated the appropriateness of each prototype GPR based on published RAND/UCLA methodology.

RESULTS

An overview of the search results is provided in this manuscript. A total of 156 studies from 307 full text articles (from 2551 initially screened records) were included, providing data on procedures characterized by: (i) colonic resection (n = 40); (ii) rectal suspension (n = 18); (iii) rectal wall excision (n = 44); (iv) rectovaginal septum reinforcement (n = 47); (v) sacral nerve stimulation (n = 7). The overall quality of evidence was poor with 113/156 (72.4%) studies providing only Oxford level IV evidence. The best evidence was extracted for rectal excisional procedures, where the majority of studies were Oxford level I or II. The five subsequent reviews provide a total of 99 SES (reflecting perioperative variables, efficacy, harms and prognostic variables) that contributed to 100 prototype GPRs covering patient selection, procedural considerations and patient counselling. The final manuscript details the 85/100 GPRs that were deemed appropriate by European Consensus (remaining 15 were all uncertain) and future research recommendations.

CONCLUSION

This manuscript and the following 6 papers suggest that the evidence base for surgical management of chronic constipation is currently poor although some expert consensus exists on best practice. Further studies are required to inform future commissioning of treatments and of research funding.

Surgery for constipation: systematic review and practice recommendations: Graded practice and future research recommendations

AIM

This manuscript forms the final of seven that address the surgical management of chronic constipation (CC) in adults. The content coalesces results from the five systematic reviews that precede it and of the European Consensus process to derive graded practice recommendations (GPR).

METHODS

Summary of review data, development of GPR and future research recommendations as outlined in detail in the 'introduction and methods' paper.

RESULTS

The overall quality of data in the five reviews was poor with 113/156(72.4%) of included studies providing only level IV evidence and only four included level I RCTs. Coalescence of data from the five procedural classes revealed that few firm conclusions could be drawn regarding procedural choice or patient selection: no single procedure dominated in addressing dynamic structural abnormalities of the anorectum and pelvic floor with each having similar overall efficacy. Of one hundred 'prototype' GPRs developed by the clinical guideline group, 85/100 were deemed 'appropriate' based on the independent scoring of a panel of 18 European experts and use of RAND-UCLA consensus methodology. The remaining 15 were all deemed uncertain. Future research recommendations included some potential RCTs but also a strong emphasis on delivery of large multinational high-quality prospective cohort studies.

CONCLUSION

While the evidence base for surgery in CC is poor, the widespread European consensus for GPRs is encouraging. Professional bodies have the opportunity to build on this work by supporting the efforts of their membership to help convert the documented recommendations into clinical guidelines.

Savanna woody encroachment is widespread across three continents

Tropical savannas are a globally extensive biome prone to rapid vegetation change in response to changing environmental conditions. Via a meta-analysis, we quantified savanna woody vegetation change spanning the last century. We found a global trend of woody encroachment that was established prior the 1980s. However, there is critical regional variation in the magnitude of encroachment. Woody cover is increasing most rapidly in the remaining uncleared savannas of South America, most likely due to fire suppression and land fragmentation. In contrast, Australia has experienced low rates of encroachment. When accounting for land use, African savannas have a mean rate annual woody cover increase two and a half times that of Australian savannas. In Africa, encroachment occurs across multiple land uses and is accelerating over time. In Africa and Australia, rising atmospheric CO₂ , changing land management and rainfall are likely causes. We argue that the functional traits of each woody flora, specifically the N-fixing ability and architecture of woody plants, are critical to predicting encroachment over the next century and that African savannas are at high risk of widespread vegetation change.

INNOVATE: A prospective cohort study combining serum and urinary biomarkers with novel diffusion-weighted magnetic resonance imaging for the prediction and characterization of prostate cancer

BACKGROUND

Whilst multi-parametric magnetic resonance imaging (mp-MRI) has been a significant advance in the diagnosis of prostate cancer, scanning all patients with elevated prostate specific antigen (PSA) levels is considered too costly for widespread National Health Service (NHS) use, as the predictive value of PSA levels for significant disease is poor. Despite the fact that novel blood and urine tests are available which may predict aggressive disease better than PSA, they are not routinely employed due to a lack of clinical validity studies. Furthermore approximately 40 % of mp-MRI studies are reported as indeterminate, which can lead to repeat examinations or unnecessary biopsy with associated patient anxiety, discomfort, risk and additional costs.

METHODS/DESIGN

We aim to clinically validate a panel of minimally invasive promising blood and urine biomarkers, to better select patients that will benefit from a multiparametric prostate MRI. We will then test whether the performance of the mp-MRI can be improved by the addition of an advanced diffusion-weighted MRI technique, which uses a biophysical model to characterise tissue microstructure called VERDICT; Vascular and Extracellular Restricted Diffusion for Cytometry in Tumours. INNOVATE is a prospective single centre cohort study in 365 patients. mp-MRI will act as the reference standard for the biomarker panel. A clinical outcome based reference standard based on biopsy, mp-MRI and follow-up will be used for VERDICT MRI.

DISCUSSION

We expect the combined effect of biomarkers and VERDICT MRI will improve care by better detecting aggressive prostate cancer early and make mp-MRI before biopsy economically viable for universal NHS adoption.

TRIAL REGISTRATION

INNOVATE is registered on ClinicalTrials.gov, with reference NCT02689271 .

Initial validation of equilibrium contrast imaging for extracellular volume quantification using a three-dimensional engineered tissue model

BACKGROUND

To test the principles underpinning equilibrium contrast imaging estimation of tissue extracellular volume (ECV) fraction, using a three-dimensional (3D) engineered tissue model with known cellular and extracellular volumes.

METHODS

Six 3D tissue models (tumoroids) consisting of cell cultures within a collagen containing hydrogel were constructed after culture centrifugation and direct measurement of the cell component volume. Measured tumoroid ECV ranged from 0.89 to 1. ECV was calculated after measuring the T1 relaxation time at 3 Tesla using inversion recovery relaxometry (TI 100-1500 ms) within the tumoroids and surrounding medium before and 375 min after spiking the medium with Gadolinium (to achieve a concentration of 1.4 mM/L). Linear regression model prediction of directly measured ECV (ECVm ) by EQ-MRI measured ECV (ECVeq ); and Bland-Altman agreement between measures was assessed.

RESULTS

The fractional cellular volume measured by EQ-MRI (ECVeq ) within the tumoroids ranged from 0.821 to 0.963. ECVeq was a good predictor of ECVm (R2 = 0.77, P = 0.02). The regression line Y-axis intercept (when X = 0) was 0.045 ± 0.019 with a slope of 1.28 ± 0.35. Bland-Altman comparison demonstrated 95% limits of agreement between -0.002 and 0.114 with a bias (SD) of 0.056 (0.03).

CONCLUSION

This study supports the principles of ECV estimation using equilibrium contrast MRI, but future development of this model may allow validation over a wider, more physiological ECV range and a greater understanding of the effect of tissue extracellular protein burden on ECV.

Degradation parameters of amaranth, barley and quinoa in alpacas fed grass hay

This study was conducted to determine the compartment 1 (C1) characteristics of alpacas (fistulated male, 7 ± 1.5 years old, 61 ± 5 kg BW) fed grass hay (GH) supplemented with amaranth (AM), quinoa (Q) and barley (B) grains. Alpacas were provided water ad libitum while housed in metabolism crates. The GH and GH plus treatments were fed at 0700 every day. Treatment periods were for 14 days in which GH or GH plus one of the grain treatments were randomly allocated. On day 14, volatile fatty acids (VFA), pH and ammonia nitrogen (NH3 -N) were determined at 1, 3, 6, 10, 14, 18 and 24 h post-feeding. C1 degradation of each feed component was also determined with the alpacas being fed GH only and the samples incubated for 0, 2, 4, 8, 14, 24, 48 and 72 h. Dry matter (DM), neutral detergent fibre (NDF) and crude protein (CP) were determined and were divided into three categories: a = immediately soluble; b = the non-soluble but degradable; and u = non-degradable/unavailable, potential extent of degradation (PE), degradation rate (c) and effective degradation (ED). C1 passage rate was determined using acid detergent insoluble ash as a marker and was calculated to be 5.5%∙h-1. Total DM intake was highest (p < 0.05) for B and resulted in a higher (p < 0.05) CP intake. GH and AM were different in mean pH (6.81 and 6.66, respectively). B NH3 -N was greater (p < 0.05) than the other treatments. Total VFA was greatest (p < 0.05) for AM, with the greatest composition differences being a shift form acetate percentage to butyrate. DM, NDF and CP degradation was different across the treatments, where PE and ED were higher (p < 0.05) for the grain treatments. The pseudo-grains AM and Q had similar C1 degradation characteristics to B.

Increasing temperatures can improve seedling establishment in arid-adapted savanna trees

Plant species are shifting their ranges in response to global climate change, thus intensifying the need to predict such changes accurately. As the environmental requirements controlling plant distribution act differently at each developmental stage, there is a need to acquire a demographic-specific understanding of the factors which determine these distributions. Here we investigated the germination niche of two common savanna species Acacia nigrescens and Colophospermum mopane, with the aims to disentangle the direct and indirect effects of temperature on seed germination and establishment and to explore the impact of higher temperatures on the establishment success of savanna trees. Under laboratory conditions, we used thermal gradient plates to determine the thermal germination niche of both species, and a water stress experiment was conducted on C. mopane to account for water-temperature interactions. Using these data we parameterised a soil-moisture model to determine germination and establishment success under field conditions at current and future temperatures (+4 °C). Based on this model, higher future temperatures will not limit germination directly, but they will reduce the number of germination events by reducing the time window of suitable available soil water. Conversely, warmer conditions will accelerate the rate of radicle extension and increase the frequency of seedling establishment events. An additional advantage of higher temperatures is that fewer seeds will germinate, resulting in slower seed bank depletion when successful seedling establishment events do occur.

Clinical validity of plasma and urinary desmosine as biomarkers for chronic obstructive pulmonary disease

BACKGROUND

Although an increased concentration of degraded elastin products in patients with chronic obstructive pulmonary disease (COPD) has been reported for many years, its clinical validity and utility remain uncertain due to technical difficulties, small study groups and the unknown relationship between exacerbation and elastin degradation. The objectives of this study were to determine the validity of urinary and blood total desmosine/isodesmosine in patients with COPD and asthma and to evaluate their relationship to exacerbation status and lung function.

METHODS

Urinary and blood desmosine levels were measured using validated isotopic dilution liquid chromatography-tandem mass spectrometry methods.

RESULTS

390 study participants were recruited from the following groups: healthy volunteers, stable asthma, stable and 'during an exacerbation' COPD. Compared with healthy non-smokers, we found increased urinary or blood desmosine levels in patients with COPD, but no differences in patients with asthma or healthy smokers. The elevation of urinary desmosine levels was associated with the exacerbation status in patients with COPD. Approximately 40% of patients with stable and 'during an exacerbation' COPD showed elevated blood desmosine levels. Blood desmosine levels were strongly associated with age and were negatively correlated with lung diffusing capacity for carbon monoxide.

CONCLUSION

The results suggest that urinary desmosine levels are raised by exacerbations of COPD whereas blood desmosine levels are elevated in a subgroup of patients with stable COPD and reduced lung diffusing capacity. The authors speculate that a raised blood desmosine level may identify patients with increased elastin degradation suitable for targeted therapy. Future prospective studies are required to investigate this hypothesis.

Patient physical characteristics and primary care physician decision making in preconception genetic screening

BACKGROUND

There has been growing emphasis on preconception care as a strategy to improve maternal and child health since the 1980s. Increasingly, development of genetic tests will require primary care providers to make decisions about preconception genetic screening. Limited research has been conducted on how primary care providers interpret patients' characteristics and use constructs, such as ethnicity and race, to decide whom to offer preconception genetic screening.

OBJECTIVE

This report assessed the influence of patient characteristics on decisions to offer preconception genetic screening.

METHODS

A web-based survey of family physicians was conducted. Physicians reviewed a clinical vignette that was accompanied by a picture of either a black or a white patient. Physicians indicated whether they would offer genetic screening, and if yes, what tests they would offer and what factors influenced their decisions.

RESULTS

The majority (69.2%) of physicians reported that they would not offer genetic screening. Respondents who reviewed the vignette accompanied by a picture of the black patient were more likely to offer screening (35% vs. 26%, p = 0.0034) and rated race as more important to their decision to offer testing than those who viewed the picture of the white patient (76% vs. 49%, p < 0.0001).

CONCLUSIONS

Our findings suggest that patient race is important to physicians when making decisions about preconception genetic testing and that decision making is influenced by patients' physical characteristics. The reticence of physicians in this sample to offer preconception screening is an important finding for public health and clinical practice.

Reducing door-to-antibiotic time in community-acquired pneumonia: Controlled before-and-after evaluation and cost-effectiveness analysis

BACKGROUND

Practice guidelines suggest that all patients hospitalised with community-acquired pneumonia (CAP) should receive antibiotics within 4 h of admission. An audit at our hospital during 1999-2000 showed that this target was achieved in less than two thirds of patients with severe CAP.

METHODS

An experienced multidisciplinary steering group designed a management pathway to improve the early delivery of appropriate antibiotics to patients with CAP. This was implemented using a multifaceted strategy. The effect of implementation was evaluated using a controlled before-and-after study design over two winter seasons (November-April 2001-2 and 2002-3). Cost-effectiveness analyses were performed from the hospital's perspective.

RESULTS

The proportion of patients receiving appropriate antibiotics within 4 h of admission to hospital increased from 33% to 56% at the intervention site, and from 32% to 36% at the control site (absolute change adjusted for differences in severity of illness 17%, p = 0.035). The cost per additional patient receiving appropriate antibiotics within 4 h was 132 pound with no post-implementation evaluation, and 456 pound for a limited post-implementation evaluation. Simple modelling from the results of a large observational study suggests that the cost per death prevented could be 3003 pound with no post-implementation evaluation, or 16,632 pound with a limited post-implementation evaluation.

CONCLUSIONS

The intervention markedly improved door-to-antibiotic time, albeit at considerable cost. It might still be a cost-effective strategy, however, to reduce mortality in CAP. Uncertainty about the cost effectiveness of such interventions is likely to be resolved only by a well-designed, cluster randomised trial.

The glial cell response to a viral vector in the aged brain

The normal aged brain undergoes pro-inflammatory changes. We investigated the effect of injecting a potential inflammatory stimulus, an adenoviral vector, on the response of microglia and astroglia in the aged brain. Groups of young (4 months) and old (31 months) male C57BL/Icrfat mice received a unilateral injection into the striatum of adenoviral vector encoding the LacZ gene. After 48 h, the mice were killed and the brains analysed for numbers of activated microglia and macrophages using the biotinylated lectin Griffonia simplicifolia as a marker; astroglia were identified by immunohistochemistry for glial fibrillary acidic protein (GFAP). The cell counts were analysed using two-way analysis of variance (anova). Transgene expression was assessed by beta-galactosidase histochemistry. The numbers of activated microglia in the striatum increased in response to the adenovirus in both young [contralateral 19.5 (3.7), ipsilateral 36 (3.0)] and old [contralateral 23.1 (9.6), ipsilateral 40.8 (6.9)] mice (two-way anova; P < 0.0001), but there was no significant difference between the two age groups. There was a significant age-related increase in the number of GFAP-positive astroglia in the uninjected, contralateral striatum [4 months, 2.5 (1.4); 31 months, 29.7 (9.3)] (two-way anova; P < 0.0001). However, there was no difference in response to the adenovirus in both young [contralateral 2.5 (1.4), ipsilateral 3.2 (1.2)] and old [contralateral 29.7 (9.3), ipsilateral 28.9 (8.2)] mice. We conclude that even though it has been argued that the aged brain is in a pro-inflammatory state, under the experimental conditions used in this study, there was no difference in the nature of the immune response between young and old mice of this strain to an adenoviral load.

Inhaler devices for asthma and COPD: choice and technique

Nurses caring for patients with asthma or chronic obstructive pulmonary disease need a good basic knowledge of the types of inhaler devices available and which may suit, for example, a very young child, an active young person or an elderly patient with dexterity problems. This Study describes the advantages and disadvantages of some commonly prescribed devices.

Diastereoselective synthesis, activity and chiral stability of cyclic alkoxyketone inhibitors of cathepsin K

The diastereoselective synthesis of a novel class of cathepsin K inhibitors together with their cathepsin K affinity and stability towards aqueous buffer is reported.

Maternal smoking cessation and relapse prevention during health care visits

BACKGROUND

Although effects of maternal smoking during pregnancy could be alleviated if women quit early in pregnancy, most do not. Relapse rates among quitters are high.

OBJECTIVE

To test the effects of a low-intensity, smoking-cessation/relapse-prevention intervention delivered by clinic staff and providers and based on stages-of-change constructs of the transtheoretical model and brief motivational interviewing techniques.

METHODS

A quasi-experimental prospective cohort design employed in obstetric, in-patient, and pediatric care delivery settings of a large health maintenance organization in Portland, Oregon. Subjects were pregnant smokers registered for their first prenatal visit. Primary outcome measures were sustained (self-reported) quit rates during pregnancy and smoking abstinence between 6 and 12 months after delivery.

RESULTS

Regression analyses found statistically significant improvement for intervention women in sustained pregnancy quit rates (OR=2.7, CI=1. 2-5.7) and on smoking abstinence between 6 and 12 months after delivery (OR=2.4, CI=1.1-5.3).

CONCLUSIONS

While these outcomes are based on self-report only, they emerged despite variable delivery of the intervention across clinics and represent clinically meaningful improvements in rates of nonsmoking. The intervention supports women who want to quit smoking during pregnancy and improves the likelihood of their remaining nonsmokers for the long term.

Synthesis, chromatographic resolution and chiroptical properties of carboxyibuprofen stereoisomers: major metabolites of ibuprofen in man

The chromatographic resolution of the four stereoisomers of carboxy-ibuprofen, a major metabolite of ibuprofen in man, was achieved using a Chiralpak AD chiral stationary phase (CSP) (J.T. Baker, Milton, Keynes, UK). The elution order of the stereoisomers was determined to be 2'S,2R;2'R,2R;2'R,2S;2'S,2S by a combination of stereoselective synthesis of diastereoisomeric mixtures and analysis of the two diastereoisomers isolated from human urine following the administration of (S)-ibuprofen. The individual stereoisomers were isolated by semipreparative chiral phase chromatography and characterized by circular dichroism spectroscopy.

Deciding about hormone therapy: validation of a model

OBJECTIVE

The purposes of this study were to (1) validate components of a decision process regarding adoption of hormone therapy and (2) compare the decision processes women used with respect to their evaluation of decision quality.

DESIGN

A sample of women participating in a population-based study of midlife women's health participated in individual in-depth interviews.

RESULTS

Content analysis of 30 recorded interviews provided evidence that each component of the decision process (precontemplation, contemplation, commitment, critical evaluation, and continuance) was replicated. Few additional codes were identified, and these could be subsumed under the phases of the original decision model.

CONCLUSIONS

Women's self-reported statuses on a screening questionnaire corresponded to the stages of the decision model coded from their interviews. What women actually decided to do (use hormone therapy or something else) was not associated with their decision process. Satisfaction with the decision, uncertainty about the decision, and other factors related to the decision were independent of the decision phases.

Reaching minority and underserved populations: the impact of the Cancer Information Service's outreach program. Part 3

Through its regional outreach program, the Cancer Information Service (CIS) develops partnership with organizations that reach minority and underserved populations and connects them with accurate cancer information and an array of support services and resources. To evaluate the usefulness, satisfaction, and impact of the CIS outreach program on partner organizations, a national random sample survey was conducted by an independent research firm in 1996. This paper focuses on the survey results of 359 special population partner organizations that identified their main audience as a specific racial or ethnic group and/or the underserved. Almost all (84% to 93%) rated the services provided by the CIS outreach program to be very important or important to meeting the goals of their projects. A large majority of these special population partners stated that the CIS provided them with the latest cancer information (67%) and National Cancer Institute (NCI) resources (83%), and more than half (57%) utilized CIS expertise to develop and plan programs. Special populations partners were more likely to use an array of CIS assistance than other CIS partners. Furthermore, they were more likely to be heavy users of CIS assistance and more likely than other CIS partners to indicate that the CIS had an important impact on their programs. The results indicate that the CIS's nationally coordinated, regionally focused outreach program provides critical support and has an important impact on the cancer-related programs of partner organizations that reach minority and underserved audiences.