Sleep disturbances, altered brain microstructure and chronic headache in youth

Chronic headache (persistent or recurrent headache for 3-months or longer) is highly prevalent among youth. While sleep disturbances have been associated with headache, their inter-relationship with brain connectivity remains unknown. This observational study examined whether self-report and actigraphy measures of sleep were associated with alterations to white matter tracts (i.e., uncinate fasciculus and cingulum) in youth with chronic headache versus healthy controls. Thirty youth aged 10-18 years with chronic headache and thirty controls underwent an MRI. Diffusion tensor images were obtained and mean fractional anisotropy values of the cingulum and uncinate were extracted. One-week prior to their MRI, youth wore an actigraph to obtain sleep duration, wake after sleep onset and sleep efficiency measures. Moreover, they completed questionnaires regarding their sleep quality and pain symptomatology. Linear regression was applied to examine the relationships between sleep (self-report and actigraphy), fractional anisotropy, and number of headache days per month. Self-report and actigraphy measures of sleep did not differ between patients and controls. However, poorer self-reported sleep quality was associated with lower fractional anisotropy values in the left uncinate (P = 0.05). Lower left uncinate fractional anisotropy was related to increased headache frequency (P = 0.002) in youth with chronic headache. Therefore, alterations to connectivity may be associated with the relationship between altered perceptions of sleep and headache chronicity.

RADCAM-A radiation camera system combining foil bolometers, AXUV diodes, and filtered soft x-ray diodes

Measurements of radiated power are critical for characterizing and optimizing tokamak performance. The RADCAM system, comprising arrays of foil bolometers, Absolute eXtreme UltraViolet (AXUV), and filtered soft x-ray diodes, has been constructed to provide improved measurements of plasma radiation on "Tokamak a Configuration Variable" (TCV). An overview of the physical geometry, electronics, and design of the system is provided. The construction of the bolometer foils together with the improved sensitivity characteristics resulting from the inclusion of an anti-reflection carbon coating are presented. The large number of lines of sight in RADCAM are shown to significantly increase the spatial resolution over the legacy system. The system calibration procedure is detailed, and the mean system sensitivity is shown to vary by less than 5% over 1000 discharges. Additionally, the methodology for cross-calibration of the AXUV diodes with the bolometer foils is presented and applied to generate high temporal resolution measurements. The RADCAM radiation camera system is a compact, versatile system that is demonstrated to provide high resolution profiles of the radiated power in TCV.

T-Cell Progenitors As A New Immunotherapy to Bypass Hurdles of Allogeneic Hematopoietic Stem Cell Transplantation

Allogeneic hematopoietic stem cell transplantation (HSCT) is the treatment of preference for numerous malignant and non-malignant hemopathies. The outcome of this approach is significantly hampered by not only graft-versus-host disease (GvHD), but also infections and relapses that may occur because of persistent T-cell immunodeficiency following transplantation. Reconstitution of a functional T-cell repertoire can take more than 1 year. Thus, the major challenge in the management of allogeneic HSCT relies on the possibility of shortening the window of immune deficiency through the acceleration of T-cell recovery, with diverse, self-tolerant, and naïve T cells resulting from de novo thymopoiesis from the donor cells. In this context, adoptive transfer of cell populations that can give rise to mature T cells faster than HSCs while maintaining a safety profile compatible with clinical use is of major interest. In this review, we summarize current advances in the characterization of thymus seeding progenitors, and their ex vivo generated counterparts, T-cell progenitors. Transplantation of the latter has been identified as a worthwhile approach to shorten the period of immune deficiency in patients following allogeneic HSCT, and to fulfill the clinical objective of reducing morbimortality due to infections and relapses. We further discuss current opportunities for T-cell progenitor-based therapy manufacturing, including iPSC cell sources and off-the-shelf strategies. These opportunities will be analyzed in the light of results from ongoing clinical studies involving T-cell progenitors.

Signature for Pain Recovery IN Teens (SPRINT): protocol for a multisite prospective signature study in chronic musculoskeletal pain

INTRODUCTION

Current treatments for chronic musculoskeletal (MSK) pain are suboptimal. Discovery of robust prognostic markers separating patients who recover from patients with persistent pain and disability is critical for developing patient-specific treatment strategies and conceiving novel approaches that benefit all patients. Given that chronic pain is a biopsychosocial process, this study aims to discover and validate a robust prognostic signature that measures across multiple dimensions in the same adolescent patient cohort with a computational analysis pipeline. This will facilitate risk stratification in adolescent patients with chronic MSK pain and more resourceful allocation of patients to costly and potentially burdensome multidisciplinary pain treatment approaches.

METHODS AND ANALYSIS

Here we describe a multi-institutional effort to collect, curate and analyse a high dimensional data set including epidemiological, psychometric, quantitative sensory, brain imaging and biological information collected over the course of 12 months. The aim of this effort is to derive a multivariate model with strong prognostic power regarding the clinical course of adolescent MSK pain and function.

ETHICS AND DISSEMINATION

The study complies with the National Institutes of Health policy on the use of a single internal review board (sIRB) for multisite research, with Cincinnati Children's Hospital Medical Center Review Board as the reviewing IRB. Stanford's IRB is a relying IRB within the sIRB. As foreign institutions, the University of Toronto and The Hospital for Sick Children (SickKids) are overseen by their respective ethics boards. All participants provide signed informed consent. We are committed to open-access publication, so that patients, clinicians and scientists have access to the study data and the signature(s) derived. After findings are published, we will upload a limited data set for sharing with other investigators on applicable repositories.

TRIAL REGISTRATION NUMBER

NCT04285112.

Virtual Reality Augments Movement During Physical Therapy: A Pragmatic Randomized Trial

OBJECTIVE

Virtual reality facilitates physical therapy via improved engagement. Although shown to benefit specific patient populations, such as stroke patients, it is less established in otherwise healthy adults and children receiving outpatient physical therapy. The primary objective was to compare total physical therapy-guided movement supplemented with virtual reality with physical therapy-guided movement alone without virtual reality.

DESIGN

This pragmatic, randomized, crossover study compared physical therapy-guided movement supplemented with virtual reality with physical therapy-guided movement alone without virtual reality in outpatients (ages 6-80 yrs). This community sample had variable physical therapy indications (injury, postoperative, chronic pain), and in pre-existing conditions, therefore, participants served as their own controls. Participants received 10 mins of both physical therapy-guided movement supplemented with virtual reality and physical therapy-guided movement alone without virtual reality separated by 5 mins. The primary outcome was differences in aggregate movement of physical therapy-guided exercises. Secondary outcomes explored OMNI rating of perceived exertion and participant and physical therapist satisfaction. Paired t tests, χ2 tests, and regression models were used to analyze differences.

RESULTS

The 41 participants (17 pediatric and 24 adult) moved significantly more during physical therapy-guided movement supplemented with virtual reality compared with physical therapy-guided movement alone without virtual reality (1120.88 vs. 672.65 m, P < 0.001), regardless of which intervention was completed first. Physical therapy-guided movement supplemented with virtual reality treatment was associated with more movement of the target limbs, lower body (P < 0.001), and upper body (P < 0.05). The OMNI rating of perceived exertion scores did not differ between those who started with physical therapy-guided movement supplemented with virtual reality or physical therapy-guided movement alone without virtual reality, and physical therapist and patient surveys endorsed physical therapy-guided movement supplemented with virtual reality.

CONCLUSIONS

Patients completed more physical therapy-guided movement during physical therapy-guided movement supplemented with virtual reality than physical therapy-guided movement alone without virtual reality, and therapists and patients supported its use. Future studies will examine finer tracking of movements.

A DL-4- and TNFα-based culture system to generate high numbers of nonmodified or genetically modified immunotherapeutic human T-lymphoid progenitors

Several obstacles to the production, expansion and genetic modification of immunotherapeutic T cells in vitro have restricted the widespread use of T-cell immunotherapy. In the context of HSCT, delayed naïve T-cell recovery contributes to poor outcomes. A novel approach to overcome the major limitations of both T-cell immunotherapy and HSCT would be to transplant human T-lymphoid progenitors (HTLPs), allowing reconstitution of a fully functional naïve T-cell pool in the patient thymus. However, it is challenging to produce HTLPs in the high numbers required to meet clinical needs. Here, we found that adding tumor necrosis factor alpha (TNFα) to a DL-4-based culture system led to the generation of a large number of nonmodified or genetically modified HTLPs possessing highly efficient in vitro and in vivo T-cell potential from either CB HSPCs or mPB HSPCs through accelerated T-cell differentiation and enhanced HTLP cell cycling and survival. This study provides a clinically suitable cell culture platform to generate high numbers of clinically potent nonmodified or genetically modified HTLPs for accelerating immune recovery after HSCT and for T-cell-based immunotherapy (including CAR T-cell therapy).

Subclinical post-traumatic stress symptomology and brain structure in youth with chronic headaches

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ACEs and PTSS did not significantly differ between patients and healthy controls.

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Patients demonstrated greater corticolimbic connectivity compared to controls.

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Greater PTSS and less corticolimbic connectivity increased headache frequency.

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Less corticolimbic connectivity may indicate greater disease progression.

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Patients may be more vulnerable to the effects of PTSS compared to controls.

Background/aims

Post-traumatic stress symptoms (PTSS) and chronic pain often co-occur at high rates in youth. PTSS may alter brain structure thereby contributing to headache chronicity. This study examined whether PTSS and altered limbic circuitry were associated with headache frequency in youth.

Methods

Thirty youth aged 10–18 years with chronic headaches and 30 age- and sex-matched controls underwent a 3T MRI scan. Volumes of the hippocampus and amygdala were obtained from T1-weighted images. Mean fractional anisotropy (FA, an index of white matter structure) axial and radial diffusivity values of the cingulum and uncinate fasciculus were extracted from diffusion-weighted images. Youth reported on their headaches daily, for one-month, and self-reported pubertal status, emotion regulation, adverse childhood experiences (ACEs) and PTSS using validated measures. Volumes of the hippocampus and amygdala and diffusivity values of the cingulum and uncinate were compared between patients and controls. Hierarchical linear regressions were used to examine the association between PTSS, subcortical volumes and/or diffusivity values and headache frequency.

Results

Mean FA values of the cingulum were higher in patients compared to controls (P = 0.02, Cohen’s d = 0.69). Greater PTSS (P = 0.04), smaller amygdala volumes (P = 0.01) and lower FA of the cingulum (P = 0.04) were associated with greater headache frequency, after accounting for age, puberty, pain duration, emotion regulation, and ACEs (Adjusted R² ≥ 0.15). Headache frequency was associated with increases in radial diffusivity (P = 0.002, Adjusted R² = 0.59), as opposed to axial diffusivity (n.s.).

Conclusions

PTSS, smaller amygdalar volume, and poorer cingulum structural connectivity were associated with headache frequency in youth, and may underlie headache chronicity.

Robust impurity detection and tracking for tokamaks

A robust impurity detection and tracking code, able to generate large sets of dust tracks from tokamak camera footage, is presented. This machine learning-based code is tested with cameras from the Joint European Torus, Doublet-III-D, and Magnum-PSI and is able to generate dust tracks with a 65-100% classification accuracy. Moreover, the number dust particles detected from a single camera shot can be up to the order of 1000. Several areas of improvement for the code are highlighted, such as generating more significant training data sets and accounting for selection biases. Although the code is tested with dust in single two-dimensional camera views, it could easily be applied to multiple-camera stereoscopic reconstruction or nondust impurities.

Ex vivo generated human T-lymphoid progenitors as a tool to accelerate immune reconstitution after partially HLA compatible hematopoietic stem cell transplantation or after gene therapy

Prolonged T-cell immunodeficiency following HLA- incompatible hematopoietic stem cell transplantation (HSCT) represents a major obstacle hampering the more widespread use of this approach. Strategies to fasten T-cell reconstitution in this setting are highly warranted as opportunistic infections and an increased risk of relapse account for high rates of morbidity and mortality especially during early month following this type of HSCT. We have implemented a feeder free cell system based on the use of the notch ligand DL4 and cytokines allowing for the in vitro differentiation of human T-Lymphoid Progenitor cells (HTLPs) from various sources of CD34+ hematopoietic stem and precursor cells (HSPCs). Co- transplantion of human T-lymphoid progenitors (HTLPs) and non- manipulated HSPCs into immunodeficient mice successfully accelerated the reconstitution of a polyclonal T-cell repertoire. This review summarizes preclinical data on the use of T-cell progenitors for treatment of post- transplantation immunodeficiency and gives insights into the development of GMP based protocols for potential clinical applications including gene therapy approaches. Future clinical trials implementing this protocol will aim at the acceleration of immune reconstitution in different clinical settings such as SCID and leukemia patients undergoing allogeneic transplantation. Apart from pure cell-therapy approaches, the combination of DL-4 culture with gene transduction protocols will open new perspectives in terms of gene therapy applications for primary immunodeficiencies.

Symptom monitoring and the uncertain threat of disease recurrence: A deductive thematic analysis with adolescent and young adult (AYA) cancer survivors

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Background: Symptom monitoring plays an important role in both the physical and psychological challenges of surviving cancer. Anecdotally, cancer survival is characterized by uncertainty, symptom-related fear, and the interpretation of normal bodily sensations as symptomatic of cancer recurrence. This fear may lead to over-vigilance of benign bodily sensations, increasing anxiety and decreasing quality of life. Yet, there are few studies investigating how cancer survivors interpret and make sense of post-cancer symptoms. These studies are needed to guide considerations for clinical practice and the development of supportive interventions. Methods: We conducted in-depth semi-structured interviews with 18 AYA cancer survivors about how they interpret, manage, and respond to physical symptoms during survivorship. Participants were 15-25 years old. The sample was diverse in terms of disease history, ethnicity (8 Hispanic), and gender (9 females, 1 nonbinary). We conducted thematic analysis using a deductive coding scheme that was developed using our Cancer Threat Interpretation (CTI) theoretical model of cognitive, affective, and behavioral processes in post-cancer symptom perception. Results: AYA cancer survivors reported experiencing anxiety in the face of common physical sensations. These sensations were often interpreted as potential signs of recurrence or as late effects of treatment. Survivors most commonly reported worries about pain and fatigue, but also other sensations such as breathlessness. We coded participant transcripts into the following themes: biased attending towards symptoms, biased interpretations of symptoms as threatening, fear and worry about symptoms, and behavioral response to symptoms. In addition, we generated a new theme that was not previously captured in the CTI model: trust in the body. Conclusions: Knowing how to appraise and respond to symptoms such as pain is a challenge for AYA cancer survivors. This rich qualitative data provides support for the CTI model and suggests future directions. The results of this study can inform how clinicians talk to their patients about symptom monitoring after treatment ends.

Concise Review: Boosting T-Cell Reconstitution Following Allogeneic Transplantation-Current Concepts and Future Perspectives

Allogeneic hematopoietic stem cell transplantation (HSCT) is the treatment of choice for a large number of malignant and nonmalignant (inherited) diseases of the hematopoietic system. Nevertheless, non‐HLA identical transplantations are complicated by a severe T‐cell immunodeficiency associated with a high rate of infection, relapse and graft‐versus‐host disease. Initial recovery of T‐cell immunity following HSCT relies on peripheral expansion of memory T cells mostly driven by cytokines. The reconstitution of a diverse, self‐tolerant, and naive T‐cell repertoire, however, may take up to 2 years and crucially relies on the interaction of T‐cell progenitors with the host thymic epithelium, which may be altered by GvHD, age or transplant‐related toxicities. In this review, we summarize current concepts to stimulate reconstitution of a peripheral and polyclonal T‐cell compartment following allogeneic transplantation such as graft manipulation (i.e., T‐cell depletion), transfusion of ex vivo manipulated donor T cells or the exogenous administration of cytokines and growth factors to stimulate host‐thymopoiesis with emphasis on approaches which have led to clinical trials. Particular attention will be given to the development of cellular therapies such as the ex vivo generation of T‐cell precursors to fasten generation of a polyclonal and functional host‐derived T‐cell repertoire. Having been tested so far only in preclinical mouse models, clinical studies are now on the way to validate the efficacy of such T‐cell progenitors in enhancing immune reconstitution following HSCT in various clinical settings. stem cells translational medicine2019;00:1–8

When pain gets stuck: the evolution of pain chronification and treatment resistance

It is well-recognized that, despite similar pain characteristics, some people with chronic pain recover, whereas others do not. In this review, we discuss possible contributions and interactions of biological, social, and psychological perturbations that underlie the evolution of treatment-resistant chronic pain. Behavior and brain are intimately implicated in the production and maintenance of perception. Our understandings of potential mechanisms that produce or exacerbate persistent pain remain relatively unclear. We provide an overview of these interactions and how differences in relative contribution of dimensions such as stress, age, genetics, environment, and immune responsivity may produce different risk profiles for disease development, pain severity, and chronicity. We propose the concept of "stickiness" as a soubriquet for capturing the multiple influences on the persistence of pain and pain behavior, and their stubborn resistance to therapeutic intervention. We then focus on the neurobiology of reward and aversion to address how alterations in synaptic complexity, neural networks, and systems (eg, opioidergic and dopaminergic) may contribute to pain stickiness. Finally, we propose an integration of the neurobiological with what is known about environmental and social demands on pain behavior and explore treatment approaches based on the nature of the individual's vulnerability to or protection from allostatic load.

A Type 1 Diabetes Genetic Risk Score Predicts Progression of Islet Autoimmunity and Development of Type 1 Diabetes in Individuals at Risk

OBJECTIVE

We tested the ability of a type 1 diabetes (T1D) genetic risk score (GRS) to predict progression of islet autoimmunity and T1D in at-risk individuals.

RESEARCH DESIGN AND METHODS

We studied the 1,244 TrialNet Pathway to Prevention study participants (T1D patients' relatives without diabetes and with one or more positive autoantibodies) who were genotyped with Illumina ImmunoChip (median [range] age at initial autoantibody determination 11.1 years [1.2-51.8], 48% male, 80.5% non-Hispanic white, median follow-up 5.4 years). Of 291 participants with a single positive autoantibody at screening, 157 converted to multiple autoantibody positivity and 55 developed diabetes. Of 953 participants with multiple positive autoantibodies at screening, 419 developed diabetes. We calculated the T1D GRS from 30 T1D-associated single nucleotide polymorphisms. We used multivariable Cox regression models, time-dependent receiver operating characteristic curves, and area under the curve (AUC) measures to evaluate prognostic utility of T1D GRS, age, sex, Diabetes Prevention Trial-Type 1 (DPT-1) Risk Score, positive autoantibody number or type, HLA DR3/DR4-DQ8 status, and race/ethnicity. We used recursive partitioning analyses to identify cut points in continuous variables.

RESULTS

Higher T1D GRS significantly increased the rate of progression to T1D adjusting for DPT-1 Risk Score, age, number of positive autoantibodies, sex, and ethnicity (hazard ratio [HR] 1.29 for a 0.05 increase, 95% CI 1.06-1.6; P = 0.011). Progression to T1D was best predicted by a combined model with GRS, number of positive autoantibodies, DPT-1 Risk Score, and age (7-year time-integrated AUC = 0.79, 5-year AUC = 0.73). Higher GRS was significantly associated with increased progression rate from single to multiple positive autoantibodies after adjusting for age, autoantibody type, ethnicity, and sex (HR 2.27 for GRS >0.295, 95% CI 1.47-3.51; P = 0.0002).

CONCLUSIONS

The T1D GRS independently predicts progression to T1D and improves prediction along T1D stages in autoantibody-positive relatives.

The metabolic syndrome and cancer: Is the metabolic syndrome useful for predicting cancer risk above and beyond its individual components?

AIMS

The metabolic syndrome (MetS) is a risk factor for cancer. However, it is not known if the MetS confers a greater cancer risk than the sum of its individual components, which components drive the association, or if the MetS predicts future cancer risk.

MATERIALS AND METHODS

We linked 20,648 participants from the Australian and New Zealand Diabetes and Cancer Collaboration with complete data on the MetS to national cancer registries and used Cox proportional hazards models to estimate associations of the MetS, the number of positive MetS components, and each of the five MetS components separately with the risk for overall, colorectal, prostate and breast cancer. Hazard ratios (HR) and 95% confidence intervals (95%CI) are reported. We assessed predictive ability of the MetS using Harrell's c-statistic.

RESULTS

The MetS was inversely associated with prostate cancer (HR 0.85; 95% CI 0.72-0.99). We found no evidence of an association between the MetS overall, colorectal and breast cancers. For those with five positive MetS components the HR was 1.12 (1.02-1.48) and 2.07 (1.26-3.39) for overall, and colorectal cancer, respectively, compared with those with zero positive MetS components. Greater waist circumference (WC) (1.38; 1.13-1.70) and elevated blood pressure (1.29; 1.01-1.64) were associated with colorectal cancer. Elevated WC and triglycerides were (inversely) associated with prostate cancer. MetS models were only poor to moderate discriminators for all cancer outcomes.

CONCLUSIONS

We show that the MetS is (inversely) associated with prostate cancer, but is not associated with overall, colorectal or breast cancer. Although, persons with five positive components of the MetS are at a 1.2 and 2.1 increased risk for overall and colorectal cancer, respectively, and these associations appear to be driven, largely, by elevated WC and BP. We also demonstrate that the MetS is only a moderate discriminator of cancer risk.

Rapid treatment-induced brain changes in pediatric CRPS

To date, brain structure and function changes in children with complex regional pain syndrome (CRPS) as a result of disease and treatment remain unknown. Here, we investigated (a) gray matter (GM) differences between patients with CRPS and healthy controls and (b) GM and functional connectivity (FC) changes in patients following intensive interdisciplinary psychophysical pain treatment. Twenty-three patients (13 females, 9 males; average age ± SD = 13.3 ± 2.5 years) and 21 healthy sex- and age-matched controls underwent magnetic resonance imaging. Compared to controls, patients had reduced GM in the primary motor cortex, premotor cortex, supplementary motor area, midcingulate cortex, orbitofrontal cortex, dorsolateral prefrontal cortex (dlPFC), posterior cingulate cortex, precuneus, basal ganglia, thalamus, and hippocampus. Following treatment, patients had increased GM in the dlPFC, thalamus, basal ganglia, amygdala, and hippocampus, and enhanced FC between the dlPFC and the periaqueductal gray, two regions involved in descending pain modulation. Accordingly, our results provide novel evidence for GM abnormalities in sensory, motor, emotional, cognitive, and pain modulatory regions in children with CRPS. Furthermore, this is the first study to demonstrate rapid treatment-induced GM and FC changes in areas implicated in sensation, emotion, cognition, and pain modulation.

The Presence of Borrelia miyamotoi, A Relapsing Fever Spirochaete, in Questing Ixodes ricinus in Belgium and in The Netherlands

Borrelia miyamotoi is a tick-borne bacterium that may cause relapsing fever in humans. As this pathogen has been discovered in Europe only recently, only little is known about its local impact on human health and its spatial distribution. In this study, we show the results of PCR screenings for B. miyamotoi in flagged Ixodes ricinus from Belgium and the Netherlands. B. miyamotoi was detected in nine of thirteen, and three of five locations from the Netherlands and Belgium, respectively. These outcomes indicate that B. miyamotoi is more spread than previously thought. The mean infection rate B. miyamotoi was 1.14% for Belgium and 3.84% for the Netherlands.

Foci report on indigenous Dermacentor reticulatus populations in Belgium and a preliminary study of associated babesiosis pathogens

The occurrence of autochthonous clinical cases of canine and equine babesiosis in Belgium during the last two decades suggests that the vector of the pathogens responsible for these diseases, Dermacentor reticulatus (Ixodida: Ixodidae), may be present in this country. Consequently, evidence for the presence of this tick species in different locations within Belgium was investigated. Four different locations were monitored by flagging in 2010; these included the locations at which D. reticulatus was previously found on a dog in 2009 and on two red deer in 2007. Two different species of tick were identified, Ixodes ricinus (Ixodida: Ixodidae) and D. reticulatus. A total of 282 D. reticulatus adult ticks (98 males, 184 females) were collected from the four sites. Ticks were found mainly from early March until the end of May and a peak in activity was apparent in March. A Babesia spp. (Piroplasmida: Babesiidae) genus-specific polymerase chain reaction test based on the amplification of a fragment of the 18S rRNA gene was used to investigate the potential presence of Babesia spp. All DNA extracts isolated from the total tick samples yielded negative results. Additional studies to accurately determine the distribution and vectorial capacity of this important tick species in Belgium are warranted.

A score for the prediction of cardiovascular events in the hypertensive aged

BACKGROUND

With few exceptions, tools used to estimate cardiovascular disease (CVD) risk in those without prior events are based mainly on data from middle-aged subjects. Given the ever increasing number of older people, many with hypertension, a risk score relevant to this group is warranted. Our aim was to develop a cardiovascular risk equation suitable for risk prediction in elderly, hypertensive populations.

METHODS

We utilized cardiovascular end point data from 4.1 years median follow-up in 5,426 hypertensive subjects without previous CVD from the Second Australian National Blood Pressure Study (ANBP2). Our risk model, based on Cox regression, was developed using 75% of subjects without evident CVD (n = 4,072), randomly selected and stratified by age and gender, and internally validated using the remaining 25%. The model was also externally validated against the Dubbo Study dataset.

RESULTS

The final model included sex, age, physical activity in the 2 weeks prior to entry into study, family history, use of anticoagulants, centrally acting antihypertensive agents or diabetes medication, and an interaction term for sex and diabetes medication. The C-statistic was 0.65 (0.62-0.67) for our predictive model on the model development dataset and 0.62 (0.57-0.67) on the internal validation dataset. The Dubbo Data C-statistic for CVD was 0.68 (95% CI 0.65-0.71).

CONCLUSIONS

All models performed similarly. Because of greater ease of implementation, we recommend that existing algorithms be extended into older age groups.

An analysis of discourses shaping mental health practitioners

A mental health practitioner (MHP) role was introduced to health services in southern England in 2003. The paper will discuss the initial phase within a longitudinal research study. A discursive approach will be adopted in order to understand how healthcare discourses constrain and provide possibilities for the emergence of a new worker role in mental health. The manner in which MHPs understand and talk about their work is socially constructed in interaction and constantly being modified by competing discourses. This paper will analyse three overarching health discourses, namely, the biomedical, person-centred and psychological discourses that have shaped MHP trainees. Discourses intersect to inform the role, where practices of nursing, psychology, medicine and occupational therapy are combined. Thus, the inclusion of physical, psychological and person-centred components of care serve as a multifaceted approach to care. This form of interprofessionalism leads MHPs one step closer in the advance towards an interdisciplinary discourse of holistic care.

New ways of working: how mental health practitioners perceive their training and role

This paper outlines advances in the mental health workforce by detailing the development, education and training of graduates from the social sciences in mental health practice. The mental health practitioner (MHP) programme is a partnership between higher education and the National Health Service to provide graduates with a new point of entry into the mental health workforce. The MHP is a new role in mental health i.e. in principle, trans-disciplinary, traversing psychology, nursing and occupational therapy. The role is informed by a bio-psychosocial philosophy of collaborative mental health care and therefore acts as a bridge between the different professions that constitute a multidisciplinary team on acute inpatient units and in the community. However, MHPs form part of the nursing team and work most closely with mental health nurses. They see their role as linked to, but other than, nursing. This paper will discuss the development of this programme and its philosophy of care, and will present outcome research on trainee perceptions and experiences of occupying the MHP role in mental health. It will present findings from the first stage of a longitudinal study (employing interviews and survey data) about trainee perceptions of their role and training before the programme commenced, 6 months into their training and at graduation.

Social support, coping, and psychological distress in mothers and fathers of pediatric transplant candidates: a pilot study

Both parents and children report significant psychological difficulties and family disruption prior to transplantation; however, there have been fewer studies examining predictors of distress in both mothers and fathers and across multiple transplant groups. Thirty-four mothers and 22 fathers participated in this pilot study. Parents completed measures during a routine tertiary pretransplant psychological evaluation. Paired sample t-test results indicated that mothers and fathers differed significantly on specific coping strategies employed, with fathers less likely to use engagement strategies than mothers. Correlation analyses demonstrated strong associations between engagement coping strategies and less psychological distress and the reverse with disengagement coping strategies for both mothers and fathers. Social support was associated with less psychological distress for mothers, but was unrelated to distress for fathers. Using regression analyses, for mothers, lack of social support, and disengagement coping predicted poor psychological outcomes. Taken together, these results suggest that assessing specific coping strategies employed by both mothers and fathers is an essential component of the pretransplant evaluation process. This study delineates areas for intervention that impact adjustment in parents of pediatric transplant candidates.

The Emerging Risk Factors Collaboration: analysis of individual data on lipid, inflammatory and other markers in over 1.1 million participants in 104 prospective studies of cardiovascular diseases

Many long-term prospective studies have reported on associations of cardiovascular diseases with circulating lipid markers and/or inflammatory markers. Studies have not, however, generally been designed to provide reliable estimates under different circumstances and to correct for within-person variability. The Emerging Risk Factors Collaboration has established a central database on over 1.1 million participants from 104 prospective population-based studies, in which subsets have information on lipid and inflammatory markers, other characteristics, as well as major cardiovascular morbidity and cause-specific mortality. Information on repeat measurements on relevant characteristics has been collected in approximately 340,000 participants to enable estimation of and correction for within-person variability. Re-analysis of individual data will yield up to approximately 69,000 incident fatal or nonfatal first ever major cardiovascular outcomes recorded during about 11.7 million person years at risk. The primary analyses will involve age-specific regression models in people without known baseline cardiovascular disease in relation to fatal or nonfatal first ever coronary heart disease outcomes. This initiative will characterize more precisely and in greater detail than has previously been possible the shape and strength of the age- and sex-specific associations of several lipid and inflammatory markers with incident coronary heart disease outcomes (and, secondarily, with other incident cardiovascular outcomes) under a wide range of circumstances. It will, therefore, help to determine to what extent such associations are independent from possible confounding factors and to what extent such markers (separately and in combination) provide incremental predictive value.

Preliminary results of a multicenter phase II trial of vinflunine (with trastuzumab in HER2+ pts) as first-line treatment in metastatic breast cancer

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Background: Vinflunine (VFL) is a new and innovative microtubule inhibitor of the vinca alkaloid class that achieves high intracellular concentrations. By inhibition of tubulin polymerization, cell proliferation is arrested leading to apoptotic death. Demonstrating anti- angiogenic and vascular disrupting activities, VFL has demonstrated significant efficacy as 2nd line chemotherapy in MBC (M. Campone, BJC 2006). This trial was designed to evaluate the response rate and safety of VFL as 1st line therapy in MBC as well as its activity in combination with trastuzumab in HER2+ MBC pts. Methods: Eligibility: 0 prior regimens for MBC, > 6 mo from adjuvant therapy, RECIST measurable disease, ECOG PS 0–2, adequate organ function, < G2 neuropathy. Treatment: 320 mg/m2 IV over 20 minutes q3 weeks; 280 mg/m2 with trastuzumab 6 mg/kg q3 weeks in HER2+ pts. Response evaluations q9 weeks; treatment continued until progression or toxicity. A total of 96 pts will be enrolled, 48 pts per each of 2 cohorts, HER2- and HER2+. Results: 18 pts are enrolled, 13 pts evaluable for toxicity and 12 pts for response. 3 pts received VFL monotherapy and 10 pts were treated with VFL + trastuzumab. Median age: 59 years (43–78). ECOG PS 0: 9 pts, 1: 3 pts, 2: 1 pt. Prior adjuvant chemo: 7 pts (54%), with 5 prior anthracyclines and 6 prior taxanes. 2 pts received adjuvant hormonal therapy only. 4 pts presented with de novo stage IV HER2+ MBC. Metastatic disease sites: liver: 6 pts, lung: 7 pts, bone: 5 pts, lymph nodes: 6 pts. 46% had 3 or more sites of organ involvement. Median of 3 cycles (range:1 - 11) was delivered. 7 pts (58%, all HER2+) had a PR and 4 pts (33%) achieved SD. Only 1 pt progressed. Heme toxicity: G3/4 neutropenia: 2 pts (16%); no febrile neutropenia was noted. G3 non-heme toxicity consisted of N/V: 2 pts and myalgia, 2 pts. There were no G4 events. 4 pts were hospitalized (vomiting: 2, cerebro-vascular accident: 1, back pain: 1 pt). 92% of pts remain free of progression at 6 months. Median TTP has not been reached. Conclusions: Vinflunine is a promising new drug with a high level of activity as first line MBC therapy, especially in combination with trastuzumab. VFL is well tolerated in this patient population with a manageable toxicity profile. Accrual to this trial continues.

[Table: see text]

Biweekly neoadjuvant gemcitabine, epirubicin, and nano-particle albumin bound (nab) paclitaxel (GEA) with tumor SPARC analysis correlated with pathologic responses: Results of a multicenter phase II trial

11060

Background: The triplet combination of gemcitabine (G), anthracyclines and taxanes have demonstrated significant activity in the metastatic as well as neoadjuvant breast cancer setting with objective response rates of 90% and pathologic CRs of 20–25% with a variety of schedules. SPARC, a poor prognostic indicator, is a glycoprotein expressed in many solid tumors, including breast cancer, and is thought to mediate active tumor transport of nab paclitaxel resulting in high intratumoral concentrations. The present tumor analysis correlates SPARC expression with pathologic responses to neoadjuvant GEA. Methods: Patients with clinical T1c-T4d and/or N0–3, M0 (T1N0M0 excluded) breast cancer, chemo naive, ECOG PS 0–2, normal LVEF, adequate organ function were treated with neoadjuvant G 2000 mg/m2, epirubicin 50 mg/m2, nab paclitaxel (A)175 mg/m2 IV q14 x 6 cycles followed by surgery. Postoperative therapy: G 2000 mg/m2 and A 220 mg/m2 q14 x 4 cycles. Neulasta 6 mg sc D2 was given with all cycles although alternative granulocyte stimulating factors was permitted. Enrollment planned for 120 pts. Results: 72 pts are enrolled, 48 patients evaluable for toxicityand pathologic responses available for 35 pts. Median age: 48 years (29–73), ECOG PS 0 - 45 pts (96%), 1 - 3 (6%), median tumor size 4.5 cm, 79% ductal, 4% lobular, 13% inflammatory. 54% ER-/PR-, 81% HER2 negative. 21 (60%) were triple negative, basal subtype. Heme toxicity was minimal: G3/4 neutropenia: 4 (8%) pts, thrombocytopenia: 3 (6%) pts. There were no episodes of febrile neutropenia. Nonheme toxicity significant for G3/4 arthraglias: 5 (10%) pts & fatigue in 3 (6%) pts. 3 pts hospitalized (infection, PE, abd pain). 1 pt developed PD during neoadjuvant therapy; 5 pts did not complete post op chemo (pt compliance: 2, PD: 2, MD discretion: 1). pCR was noted in both breast and LNs in 7 pts (20%) and pPR in 26 (74%). Conclusions: Neoadjuvant dose dense GEA is feasible and extremely well tolerated. Significant activity with a pCR of 20% is evident with the basal subtype of breast cancer. SPARC tumor analysis correlations with observed pathologic responses will be presented and updated with the continuing accrual to this trial.

No significant financial relationships to disclose.

Importance of timing of PET scan after therapy in oncology

13014

Background: Growth factors are routine after systemic chemotherapy both as primary and secondary prophylaxis. Similarly PET scan is increasingly used for initial staging and follow-up of response. Timing of both is important since false positive results are noted due to high sensitivity of the test. Methods: Records of four patients with super positive PET scan with diffuse uptake in the axial skeleton were analyzed for the timing of administration of white cell growth factor before imaging and confirmation of bone finding with a follow- up bone scan to rule out mets. Results: Two patients were treated for stage IIIB/IV non-small cell lung cancer, one patient with breast cancer was receiving adjuvant treatment for stage IIIA breast cancer, and the last patient was treated for metastatic pancreatic cancer. All had negative scans for bone mets before the start of treatment. PET scan was done for staging in one patient and evaluation of abnormal CT scan in another, and follow-up of response in two patients. It was inadvertently obtained 10–14 days after the filgrastim/pefilgrastim administration. Based on the unusual uptake in bony skeleton, bone scan was ordered to rule out bone mets in all four patients. Since their bone scans were negative for metastatic disease they were continued on their treatment plan as scheduled. Conclusions: PET scan has been sparingly used until 1990’s due to high cost. Currently Medicare has approved it for wider indications. PET scan in general has high sensitivity and low specificity and false positive results are more common from metabolically active infection and inflammation. Granulocyte colony stimulating factor used with cancer treatments can increase the FDG uptake in PET scan. Diffuse increased uptake in bone marrow by PET scan can be seen in reactive marrow following growth factor therapy. Usually FDG uptake is modest with SUV of less than 3, uniform and diffuse if due to growth factor stimulation in contrast to greater intensity with SUV around 6 with non uniform distribution. Awareness of this pitfalls associated with PET scan allows image interpretation accurately. PET-CT fusion may increase the diagnostic specificity. However timing of the scan in relation to growth factor administration may also help to avoid the unnecessary anxiety and further follow up testing which adds to the health care costs.

No significant financial relationships to disclose.

Cost-effectiveness of referral for generic care or problem-solving treatment from community mental health nurses, compared with usual general practitioner care for common mental disorders: Randomised controlled trial

BACKGROUND

UK general practitioners (GPs) refer patients with common mental disorders to community mental health nurses.

AIMS

To determine the effectiveness and cost-effectiveness of this practice.

METHOD

Randomised trial with three arms: usual GP care, generic mental health nurse care, and care from nurses trained in problem-solving treatment; 98 GPs in 62 practices referred 247 adult patients with new episodes of anxiety, depression and life difficulties, to 37 nurses.

RESULTS

There were 212 (86%) and 190 (77%) patients followed up at 8 and 26 weeks respectively. No significant differences between groups were found in effectiveness at either point. Mean differences in Clinical Interview Schedule - Revised scores at 26 weeks compared with GP care were -1.4 (95% CI -5.5 to 2.8) for generic nurse care, and 1.1 (-2.9 to 5.1) for nurse problem-solving. Satisfaction was significantly higher in both nurse-treated groups. Mean extra costs per patient were 283 pound (95% CI154-411) for generic nurse care, and 315 pound (183-481) for nurse problem-solving treatment.

CONCLUSIONS

GPs should not refer unselected patients with common mental disorders to specialist nurses. Problem-solving should be reserved for patients who have not responded to initial GP care.

A phase II trial of biweekly pemetrexed (P) and gemcitabine (G) in the first-line treatment (tx) of patients (pts) with advanced non-small cell lung cancer (NSCLC)

17054

Background: P and G are active and well-tolerated non-platinum agents used in the tx of NSCLC. Previous trials have combined P and G in the first-line NSCLC setting using a 21D schedule. This trial examined the safety and activity of biweekly P/G. Methods: Theprimary endpoints of this single center community-based phase II study were toassess the safety and response rate (RR) of P/G in pts with previously untreated stage III (unresectable) or IV NSCLC. Tx included: P 500mg/m2 IV D1 and G 1500mg/m2 IV D1 Q 14D for 8–12 cycles. Pts also received folate and B12 prophylaxis. Pts were restagedafter 4 cycles. Eligibility included:measurable disease, ECOG PS 0–2, adequate organ function, informed consent, and no active brain metastases. Analysis was by intent to treat. Results: Thirty-five pts were enrolled between 5/05 and 8/05. The median follow-upis 6 months (3.5–7.5 months). Baseline characteristics include: medianage 65 years (41–85); male/female, 71%/29%; ECOG PS 0,1,2:17%/71%/12%; and histology, adenocarcinoma (34%), large cell (29%), squamous (11%), mixed or not specified (26%). The median number of cycles delivered was 8 (1–12). Grade (G)3/4 non-hematologic toxicity included:chest pain (6%), constipation (6%), fatigue (17%), hypercalcemia (6%), dyspnea (9%), and tachyarrhythmia (9%). G3/4 hematologic toxicity included: neutropenia(51%), anemia (8%), and thrombocytopenia (3%). G3/4 febrile neutropenia occurred in 14%. There were notx-related deaths. Response data are availablefor 35 pts. Complete/partial responses for all pts were observed in 0 pts/7pts, respectively, for an overall RR of 20% (95% CI 10%-36%, 1 pt unconfirmed by RECIST criteria). Fifty-four percentof pts had stable disease, and 14% had disease progression(4 pts were unevaluable.) Six-month progression-free survival (PFS) andoverall survival (OS) were 51% and 67%, respectively. Median PFS and OS have not been reached. Conclusions: Biweekly P/G is a safe and well-tolerated regimen with RRsimilar to other standard first-line regimens for the tx of pts with advanced NSCLC, and further study is warranted. Median and 1-year PFSand OS endpoints have not been reached in this trial.

[Table: see text]

Phase II pilot trial of imatinib mesylate with weekly docetaxel in metastatic breast cancer

10716

Background: Overexpression of platelet derived growth factor receptor (PDGFR) has been associated with breast cancer tumor progression and may serve as a potential target for therapy. Inhibition of PDGFR signaling in tumor stroma represents a novel strategy that has demonstrated enhanced chemotherapy antitumor effects, decreased tumor interstitial fluid pressure as well as increased tumor transcapillary transport. Imatinib mesylate (G) is a potent PDGFR tyrosine kinase antagonist. This phase II pilot study evaluates the feasibility, toxicity, and efficacy of imatinib administered with docetaxel as a strategy to enhance docetaxel’s chemotherapeutic effects in metastatic breast cancer (MBC). Methods: Eligibility requirements: 0–1 prior regimens for MBC, > 6 months from prior adjuvant taxanes, RECIST measurable disease, ECOG PS 0–2, adequate organ function, < G2 neuropathy. Treatment: docetaxel 30 mg/m2 IV weekly 3 of 4 weeks. Imatinib mesylate 600 mg po QD. Pts were evaluated for response every 8 weeks; treatment continued until progression or toxicity. Results: 7 pts have been enrolled to date. Median age is 61, all with ECOG PS 0. 5 pts received prior adjuvant therapy; 2 pts received prior taxanes. 43% received prior hormonal therapy. Only 1 pt was ER+/PR+. Hematologic toxicity was mild, consisting only of G3/4 anemia in 2 pts and G3 thrombocytopenia in 1. No febrile neutropenia was noted. Nonhematologic toxicity was characterized primarily by G3 GI toxicity: 4 pts diarrhea, 3 N, V, 1 anorexia, 1 abdominal pain. This was attributed to imatinib in all but 1 pt, in whom both drugs were implicated. 2 pts were removed from treatment and 3 pts required dose reductions, all due to GI toxicity consisting of N, V, and diarrhea. 3 pts experienced dose interruptions and 2 pts exhibited disease progression. Conclusion: These early preliminary results demonstrate imatinib mesylate, in combination with weekly docetaxel as a strategy to inhibit breast cancer PDGFR signaling, is feasible. GI toxicity with this combination was prominent and warrants dose modifications. Updated toxicity and efficacy data will be presented.

[Table: see text]

Phase II trial of gemcitabine and carboplatin, plus trastuzumab in HER2+ patients as first line therapy in metastatic breast cancer

10590

Background: Gemcitabine (G) and carboplatin (C) demonstrate significant preclinical synergy together as well as in combination with trastuzumab (H) in metastatic breast cancer (MBC) pts. This multicenter phase II trial evaluates the efficacy and safety of G + C with trastuzumab in HER2 + pts as 1st line therapy in MBC. Methods: Eligibility requirements: females > 18 with no prior regimens for MBC, ECOG 0–2, RECIST bidimensional disease, and adequate organ function. FISH HER2 + pts received H with GC. Treatment: G 1,000 mg/m2 D1& 8 with C AUC 5 D1 in the first 20 pts. Following a toxicity assessment revealing significant myelosuppression, C was administered in subsequent pts at AUC 4. 14 HER2+ pts received H 8 mg/kg loading dose followed by 6 mg/kg q21 days. Pts were evaluated for response after 9 weeks; treatment continued until progression or toxicity except in HER2+ pts who received up to 6 cycles GCH followed by single agent H. Results: Between 11/03 & 11/05, 45 pts have been treated: median age 55 for GC, 65 for GCH, ECOG 0/1 22/23. 19 pts were chemonaive. 26 pts received prior adjuvant chemotherapy: 20 pts adjuvant anthracyclines (A) & taxanes (T), 3 only prior A and 3 prior T. 73% had 2 or more metastatic sites of disease. 31 pts received GC & 14 pts received GCH. 18 of 41 evaluable pts (44%) had objective responses (PR 16, CR 2) with 17 pts (42%) exhibiting SD & 6 pts PD (15%). 91% of AT pretreated pts demonstrated SD or better. 9 remain on study. 6 went off study due to heme related toxicities and 9 due to MD discretion [4 max benefit, 3 XRT]. Median # of cycles was 5. Combined G3/4 hematologic toxicity was notable for 66% neutropenia (only 1 FN), 55% thrombocytopenia, and 32% anemia, predominately occurring at the carboplatin AUC 5 dose level. Transfusions of PRBCs and plts were administered in 14 and 8 pts respectively. Nonhematologic toxicity was minimal and remarkable for G3/4 fatigue in 20%. Conclusions: In FISH HER2+ pts, the addition of trastuzumab to GC yielded a 50% RR, with no evident cardiotoxicity. The combination of gemcitabine with carboplatin AUC 4 is active, albeit with moderate hematologic toxicity, warranting further exploration of alternate GC ± H schedules in breast cancer.

[Table: see text]

Ultrasonic treatment to improve anaerobic digestibility of dairy waste streams

The dairy-processing industry generates various types of organic wastes, which are utilised as stock feed, for anaerobic digestion, spread on land or alternatively land-filled at high costs. Owing to the generation of renewable energy, anaerobic digestion is an attractive option for many factories. To enhance the biological degradation process, a mechanical disintegration of various waste dairy streams was undertaken. While the successful application of ultrasonic treatment has been reported for various municipal waste streams, limited information was available for dairy industry applications. The results of this study showed that ultrasonic treatment can improve the digestibility of the more problematic dairy waste streams, such as sludges, by breaking down micro-organisms' cell walls and releasing soluble cell compounds. For more soluble streams, such as dairy factory effluent, an increased gas production was observed and attributed to the reduced particle size of the fat globules.

A trial of problem-solving by community mental health nurses for anxiety, depression and life difficulties among general practice patients. The CPN-GP study

OBJECTIVES

To compare the effectiveness of community mental health nurse (CMHN) problem-solving and generic CMHN care, against usual general practitioner (GP) care in reducing symptoms, alleviating problems, and improving social functioning and quality of life for people living in the community with common mental disorders; and to undertake a cost comparison of each CMHN treatment compared with usual GP care.

DESIGN

A pragmatic, randomised controlled trial with three arms: CMHN problem-solving, generic CMHN care and usual GP care.

SETTING

General practices in two southern English counties were included in the study. CMHNs were employed by local NHS trusts providing community mental health services.

PARTICIPANTS

Participants were GP patients aged 18--65 years with a new episode of anxiety, depression or reaction to life difficulties and had to score at least 3 points on the General Health Questionnaire-12 screening tool. Symptoms had to be present for a minimum of 4 weeks but no longer than 6 months.

INTERVENTIONS

Patients were randomised to one of three groups: (1) CMHN problem-solving treatment, (2) generic CMHN treatment, or (3) usual GP care. All three groups of patients remained free to consult their GPs throughout the course of the study, and could be prescribed psychotropic drug treatments.

MAIN OUTCOME MEASURES

Patients were assessed at baseline, and 8 weeks and 26 weeks after randomisation. The primary outcome measure was psychological symptoms measured on the Clinical Interview Schedule -- Revised. Other measures included social functioning, health-related quality of life, problem severity and satisfaction. The economic outcomes were evaluated with a cost--utility analysis.

RESULTS

Twenty-four CMHNs were trained to provide problem-solving under supervision, and another 29 were referred patients for generic support. In total, 247 patients were randomised to the three arms of the study, referred by 98 GPs in 62 practices. All three groups of patients were greatly improved by the 8-week follow-up. No significant differences were found between the groups at 8 weeks or 26 weeks in symptoms, social functioning or quality of life. Greater satisfaction with treatment was found in the CMHN groups. CMHN care represented a significant additional health service cost and there were no savings in sickness absence.

CONCLUSIONS

The study found that specialist mental health nurse support is no better than support from GPs for patients with anxiety, depression and reactions to life difficulties. The results suggest that healthcare providers could consider adopting policies of restricting referrals of unselected patients with common mental disorders to specialist CMHNs, although there may be other roles in primary care that CMHNs could play effectively. Further research should address the predictors of chronicity in common mental disorders and target extra treatment. More research is also needed into the effectiveness and cost-effectiveness of problem-solving treatment for other disorders, of facilitated self-help treatments for common mental disorders and of CMHN care for people with severe and enduring mental illnesses, as well as the prevention of mental disorders.

The financial cost of optimising blood pressure control

We have investigated the financial costs of attempts to optimise blood pressure control in patients referred to our blood pressure clinic. At first referral, the average blood pressure in the 262 patients studied were 167/97 mmHg and the monthly costs of the antihypertensive drugs was 23.44 pounds. After 1 year of clinic attendance, the blood pressure was reduced to 149/87 mmHg, and the average drug costs had risen to 30.68 pounds. For drug expenditure alone, the cost of reducing systolic blood pressure by 1 mmHg was 0.36p pounds (Euro 0.55, USD 0.55) and for diastolic blood pressure the cost-was 0.72p pounds (Euro 1.12, USD 1.13).

Assessment of control measures to achieve a food safety objective of less than 100 CFU of Listeria monocytogenes per gram at the point of consumption for fresh precut iceberg lettuce

The important new concept of the food safety objective (FSO) offers a strategy to translate public health risk into a definable goal such as a specified maximum frequency or concentration of a hazardous agent in a food at the time of consumption that is deemed to provide an appropriate level of health protection. For the foodborne pathogen Listeria monocytogenes, there is a proposed FSO of < 100 CFU/g in ready-to-eat (RTE) products at the time of consumption. Fresh precut iceberg lettuce is one of these RTE products. In this study, we worked with a commercial manufacturer to evaluate the effectiveness of two antimicrobial washing agents (sodium hypochlorite and a mixture of hydrogen peroxide and peroxyacetic acid) against L. monocytogenes under simulated fresh precut washing conditions and evaluated the growth potential of this pathogen on lettuce packaged in a gas-permeable film and stored at 4 or 8 degrees C for 14 days. We used the results of this experiment to demonstrate how the commercial manufacturer could meet the FSO for L. monocytogenes in fresh precut lettuce through the application of performance, process, and microbiological criteria.