Signalling between the sexes during pollen tube reception

Plant reproduction is a complex, highly-coordinated process in which a single, male germ cell grows through the maternal reproductive tissues to reach and fertilise the egg cell. Focussing on Arabidopsis thaliana, we review signalling between male and female partners which is important throughout the pollen tube journey, especially during pollen tube reception at the ovule. Numerous receptor kinases and their coreceptors are implicated in signal perception in both the pollen tube and synergid cells at the ovule entrance, and several specific peptide and carbohydrate ligands for these receptors have recently been identified. Clarifying the interplay between these signals and the downstream responses they instigate presents a challenge for future research and may help to illuminate broader principles of plant cell-cell communication.

Conserved cellular patterning in the mesophyll of rice leaves

The mesophyll cells of grass leaves, such as rice, are traditionally viewed as displaying a relatively uniform pattern, in contrast to the clear distinctions of palisade and spongy layers in typical eudicot leaves. This quantitative analysis of mesophyll cell size and shape in rice leaves reveals that there is an inherent pattern in which cells in the middle layer of the mesophyll are larger and less circular and have a distinct orientation of their long axis compared to mesophyll cells in other layers. Moreover, this pattern was observed in a range of rice cultivars and species. The significance of this pattern with relation to potential photosynthetic function and the implication of the widespread use of middle layer mesophyll cells as typical of the rice leaf have been investigated and discussed.

Severe maternal morbidity trends over 20 years in a tertiary referral stand-alone maternity unit

OBJECTIVE

Severe maternal morbidity (SMM) is a better indicator of quality of care than maternal mortality, which is a rare event. Risk factors such as advanced maternal age, caesarean section (CS) and obesity are increasing. The aim of this study was to examine the rate and trends in SMM at our hospital over a 20-year period.

STUDY DESIGN

Retrospective review was performed of cases of SMM from January 1st 2000 to December 31st 2019. Yearly rates for SMM and Major Obstetric Haemorrhage (MOH) were calculated (per 1000 maternities) and linear regression analysis was used to model the trends over time. Average SMM and MOH rates were also calculated for the periods 2000-2009 and 2010-2019 and compared using a chi-square test. The patient demographics of the SMM group were compared to the background population delivered at our hospital using a chi-square test.

RESULTS

702 women with SMM were identified out of 162,462 maternities over the study period yielding an incidence of 4.3 per 1000 maternities. When the two time periods (2000-2009 and 2010-2019) are compared, the rate of SMM increased 2.4 vs 6.2 (p < 0.001), largely due to an increase in MOH 1.72 vs 3.86 (p < 0.001) and pulmonary embolus (PE) also increased 0.2 vs 0.5 (p = 0.012). Intensive-care unit (ICU) transfer rates more than doubled 0.19 vs 0.44 (p = 0.006). Eclampsia rates decreased 0.3 vs 0.1 (p = 0.047) but the rate of peripartum hysterectomy 0.39 vs 0.38 (p = 0.495), uterine rupture 0.16 vs 0.14 (p = 0.867), cardiac arrest (0.04 vs 0.04) and cerebrovascular accidents (CVA) (0.04 vs 0.04) remained unchanged. Maternal age > 40 years 9.7% vs 5% (p = 0.005), previous CS 25.7% vs 14.4%; p < 0.001 and multiple pregnancy 8 vs 3.6% (p = 0.002) were more prevalent in the SMM cohort compared to the hospital population.

CONCLUSIONS

Overall, rates of SMM have increased threefold and transfer for ICU care has doubled over 20 years in our unit. The main driver is MOH. The rate of eclampsia has decreased and peripartum hysterectomy, uterine rupture, CVA and cardiac arrest remain unchanged. Advanced maternal age, previous caesarean delivery and multiple pregnancy were more prevalent in the SMM cohort compared to the background population.

The influences of stomatal size and density on rice abiotic stress resilience

A warming climate coupled with reductions in water availability and rising salinity are increasingly affecting rice (Oryza sativa) yields. Elevated temperatures combined with vapour pressure deficit (VPD) rises are causing stomatal closure, further reducing plant productivity and cooling. It is unclear what stomatal size (SS) and stomatal density (SD) will best suit all these environmental extremes. To understand how stomatal differences contribute to rice abiotic stress resilience, we screened the stomatal characteristics of 72 traditionally bred varieties. We found significant variation in SS, SD and calculated anatomical maximal stomatal conductance (gsmax ) but did not identify any varieties with SD and gsmax as low as transgenic OsEPF1oe plants. Traditionally bred varieties with high SD and small SS (resulting in higher gsmax ) typically had lower biomasses, and these plants were more resilient to drought than low SD and large SS plants, which were physically larger. None of the varieties assessed were as resilient to drought or salinity as low SD OsEPF1oe transgenic plants. High SD and small SS rice displayed faster stomatal closure during increasing temperature and VPD, but photosynthesis and plant cooling were reduced. Compromises will be required when choosing rice SS and SD to tackle multiple future environmental stresses.

Defining the scope for altering rice leaf anatomy to improve photosynthesis: a modelling approach

Leaf structure plays an important role in photosynthesis. However, the causal relationship and the quantitative importance of any single structural parameter to the overall photosynthetic performance of a leaf remains open to debate. In this paper, we report on a mechanistic model, eLeaf, which successfully captures rice leaf photosynthetic performance under varying environmental conditions of light and CO₂ . We developed a 3D reaction-diffusion model for leaf photosynthesis parameterised using a range of imaging data and biochemical measurements from plants grown under ambient and elevated CO₂ and then interrogated the model to quantify the importance of these elements. The model successfully captured leaf-level photosynthetic performance in rice. Photosynthetic metabolism underpinned the majority of the increased carbon assimilation rate observed under elevated CO₂ levels, with a range of structural elements making positive and negative contributions. Mesophyll porosity could be varied without any major outcome on photosynthetic performance, providing a theoretical underpinning for experimental data. eLeaf allows quantitative analysis of the influence of morphological and biochemical properties on leaf photosynthesis. The analysis highlights a degree of leaf structural plasticity with respect to photosynthesis of significance in the context of attempts to improve crop photosynthesis.

Estimating uncertainty: A Bayesian approach to modelling photosynthesis in C3 leaves

The Farquhar-von Caemmerer-Berry (FvCB) model is extensively used to model photosynthesis from gas exchange measurements. Since its publication, many methods have been developed to measure, or more accurately estimate, parameters of this model. Here, we have created a tool that uses Bayesian statistics to fit photosynthetic parameters using concurrent gas exchange and chlorophyll fluorescence measurements whilst evaluating the reliability of the parameter estimation. We have tested this tool on synthetic data and experimental data from rice leaves. Our results indicate that reliable parameter estimation can be achieved whilst only keeping one parameter, K_m , that is, Michaelis constant for CO₂ by Rubisco, prefixed. Additionally, we show that including detailed low CO₂ measurements at low light levels increases reliability and suggests this as a new standard measurement protocol. By providing an estimated distribution of parameter values, the tool can be used to evaluate the quality of data from gas exchange and chlorophyll fluorescence measurement protocols. Compared to earlier model fitting methods, the use of a Bayesian statistics-based tool minimizes human interaction during fitting, reducing the subjectivity which is essential to most existing tools. A user friendly, interactive Bayesian tool script is provided.

OS7.4 Calculating the net clinical benefit in brain tumor clinical trials by combining survival and health-related quality of life data using two methods: quality adjusted survival effect sizes (QASES) and joint modelling (JM)

BACKGROUND

The impact of treatment on both the quality and the quantity of life, i.e. the ‘net clinical benefit’, should be considered to inform glioma patients and facilitate shared decision making. We applied two methods (i.e. Quality Adjusted Effect Sizes (QASES) and Joint Modelling (JM)) that combine survival and health-related quality of life (HRQoL) data into one outcome, to gain insight in the net clinical benefit of a treatment strategy. In addition, we assessed if both methods result in similar interpretations.

MATERIAL AND METHODS

We calculated the net clinical benefit in one randomized controlled trial, EORTC 26951 comparing radiotherapy (RT) + PCV chemotherapy versus RT alone, as a proof of concept for other trials. With the QASES method, effect sizes for differences in survival and HRQoL between treatment arms were calculated. Next, the combined effect size can be determined by weighing the emphasis put on survival or HRQoL (e.g. survival more important). JM allows simultaneous modeling of a longitudinal outcome (HRQoL), and a time-to event outcome (survival). HRQoL scales/items that were selected for primary analysis in the main study were also selected for this analysis: fatigue, global health, social functioning, communication deficit, seizures, physical functioning, and nausea/vomiting.

RESULTS

288/386 patients completed baseline HRQoL forms and were included in the analysis. Overall survival (OS) was significantly longer with combined treatment (difference of 10.8 months). In contrast, the percentage of patients who experienced a clinically relevant deterioration (≥10 points) in nausea/vomiting, fatigue, social functioning and global health up to one year after treatment compared to baseline was larger in the RT+PCV arm. The QASES corresponded to a reduction in the median OS difference from 10.8 months to 6.8 months when adjusted for the HRQoL scales/items, when given equal weights to OS and HRQoL. JM analyses resulted in a theoretical loss of treatment effect in OS of 2–6% when adjusting for HRQoL.

CONCLUSION

Both methods showed that adjusting for the impact of treatment on a relevant HRQoL parameter reduced the survival benefit in the experimental treatment arm compared to standard treatment arm. Applying these methods may facilitate communicating the impact of treatment to patients in clinical practice.

Investigating the microstructure of plant leaves in 3D with lab-based X-ray computed tomography

BACKGROUND

Leaf cellular architecture plays an important role in setting limits for carbon assimilation and, thus, photosynthetic performance. However, the low density, fine structure, and sensitivity to desiccation of plant tissue has presented challenges to its quantification. Classical methods of tissue fixation and embedding prior to 2D microscopy of sections is both laborious and susceptible to artefacts that can skew the values obtained. Here we report an image analysis pipeline that provides quantitative descriptors of plant leaf intercellular airspace using lab-based X-ray computed tomography (microCT). We demonstrate successful visualisation and quantification of differences in leaf intercellular airspace in 3D for a range of species (including both dicots and monocots) and provide a comparison with a standard 2D analysis of leaf sections.

RESULTS

We used the microCT image pipeline to obtain estimates of leaf porosity and mesophyll exposed surface area (S_mes) for three dicot species (Arabidopsis, tomato and pea) and three monocot grasses (barley, oat and rice). The imaging pipeline consisted of (1) a masking operation to remove the background airspace surrounding the leaf, (2) segmentation by an automated threshold in ImageJ and then (3) quantification of the extracted pores using the ImageJ 'Analyze Particles' tool. Arabidopsis had the highest porosity and lowest S_mes for the dicot species whereas barley had the highest porosity and the highest S_mes for the grass species. Comparison of porosity and S_mes estimates from 3D microCT analysis and 2D analysis of sections indicates that both methods provide a comparable estimate of porosity but the 2D method may underestimate S_mes by almost 50%. A deeper study of porosity revealed similarities and differences in the asymmetric distribution of airspace between the species analysed.

CONCLUSIONS

Our results demonstrate the utility of high resolution imaging of leaf intercellular airspace networks by lab-based microCT and provide quantitative data on descriptors of leaf cellular architecture. They indicate there is a range of porosity and S_mes values in different species and that there is not a simple relationship between these parameters, suggesting the importance of cell size, shape and packing in the determination of cellular parameters proposed to influence leaf photosynthetic performance.

Cell density and airspace patterning in the leaf can be manipulated to increase leaf photosynthetic capacity

The pattern of cell division, growth and separation during leaf development determines the pattern and volume of airspace in a leaf. The resulting balance of cellular material and airspace is expected to significantly influence the primary function of the leaf, photosynthesis, and yet the manner and degree to which cell division patterns affect airspace networks and photosynthesis remains largely unexplored. In this paper we investigate the relationship of cell size and patterning, airspace and photosynthesis by promoting and repressing the expression of cell cycle genes in the leaf mesophyll. Using microCT imaging to quantify leaf cellular architecture and fluorescence/gas exchange analysis to measure leaf function, we show that increased cell density in the mesophyll of Arabidopsis can be used to increase leaf photosynthetic capacity. Our analysis suggests that this occurs both by increasing tissue density (decreasing the relative volume of airspace) and by altering the pattern of airspace distribution within the leaf. Our results indicate that cell division patterns influence the photosynthetic performance of a leaf, and that it is possible to engineer improved photosynthesis via this approach.

Esophagogastric junction outflow obstruction is often associated with coexistent abnormal esophageal body motility and abnormal bolus transit

Currently, the diagnosis of esophageal motility disorders is in part based upon a hierarchical algorithm in which abnormalities of the esophagogastric junction (EGJ) is prioritized. An important metric in evaluating the EGJ is the integrated relaxation pressure (IRP). Patients who do not have achalasia but are found to have an elevated IRP are diagnosed with EGJ outflow obstruction. It has been our observation that a subset of these patients also has a second named motility disorder and may also have abnormal bolus transit. The aim of this study is to determine the frequency of abnormal body motility and or abnormal bolus movement in patients with EGJ outflow obstruction. Further, in an effort to evaluate the potential clinical value in measuring bolus transit as a complement to esophageal manometry, specifically in patients with EGJ outflow obstruction, we analyzed the presenting symptoms of these patients. A total of 807 patients with a mean age of 53 years completed esophageal function testing with impedance monitoring and high-resolution manometry between January 2012 and October 2016. There were 74 patients with achalasia who were excluded from the study. Of the remaining 733 patients, 138 (19%) had an elevated IRP and were given a diagnosis of EGJ outflow obstruction. Among these patients, 56 (40%) were diagnosed with an abnormal motility pattern to liquids (ineffective esophageal motility = 28, distal esophageal spasm = 19, Jackhammer = 6), of which 44 (76%) had abnormal bolus transit to liquids, viscous, or both. In contrast, there were 82 patients with EGJ outflow obstruction and normal esophageal motility, of which 33 (40%) had abnormal bolus transit. Patients with preserved esophageal motility and EGJ outflow obstruction were then evaluated. Of the 733 patients, 299 (40%) had intact esophageal motility. Of the 299 patients with normal esophageal motility, 56 patients had an elevated IRP, of which 16 (28%) had abnormal bolus transit. There were 243 (33%) patients with intact esophageal motility and normal IRP. Of these, 56 (23%) patients had abnormal bolus transit. Among patients with abnormal bolus transit, the two most commonly presenting symptoms were dysphagia and heartburn. A substantial percentage of patients with EGJ outflow obstruction have abnormal esophageal body motility and or abnormal bolus transit. The clinical implications of EGJ outflow obstruction need to be further elucidated as current criteria do not allow for the description of other abnormalities in esophageal motility and bolus transit among patients who are given the diagnosis of EGJ outflow obstruction.

A double-blind, placebo-controlled randomized trial of creatine for the cancer anorexia/weight loss syndrome (N02C4): an Alliance trial

BACKGROUND

Multiple pilot studies, including one in colorectal cancer patients, suggest that creatine, an amino acid derivative, augments muscle, improves strength, and thereby could palliate the cancer anorexia/weight loss syndrome.

PATIENTS AND METHODS

In this randomized, double-blind, placebo-controlled trial, incurable patients with this syndrome were assigned creatine (20 g/day load×5 days followed by 2 g/day orally) versus identical placebo. Patients were weighed once a week for 1 month and then monthly. Patients were also assessed over 1 month for appetite and quality of life (validated questionnaires), fist grip strength, body composition (bioelectrical impedance), and adverse events. The primary endpoint was 10% or greater weight gain from baseline during the first month.

RESULTS

Within this combined cohort of 263 evaluable patients (134 received creatine and 129 placebo), only 3 gained ≥10% of their baseline weight by 1 month: two creatine-treated and the other placebo-exposed (P = 1.00). Questionnaire data on appetite, quality of life, and activities of daily living showed no statistically significant differences between groups. Similarly, no statistically significant differences between groups were observed for fist-grip strength or body composition. Rates and severity of adverse events were comparable between groups. Finally, a median survival of 230 and 239 days were observed in the creatine and placebo groups, respectively (P = 0.70).

CONCLUSION

Creatine, as prescribed in this trial, had no effect on the cancer anorexia/weight loss syndrome.

Van der Waals pressure and its effect on trapped interlayer molecules

Van der Waals assembly of two-dimensional crystals continue attract intense interest due to the prospect of designing novel materials with on-demand properties. One of the unique features of this technology is the possibility of trapping molecules between two-dimensional crystals. The trapped molecules are predicted to experience pressures as high as 1 GPa. Here we report measurements of this interfacial pressure by capturing pressure-sensitive molecules and studying their structural and conformational changes. Pressures of 1.2±0.3 GPa are found using Raman spectrometry for molecular layers of 1-nm in thickness. We further show that this pressure can induce chemical reactions, and several trapped salts are found to react with water at room temperature, leading to two-dimensional crystals of the corresponding oxides. This pressure and its effect should be taken into account in studies of van der Waals heterostructures and can also be exploited to modify materials confined at the atomic interfaces.

Early intervention of patients at risk for acute respiratory failure and prolonged mechanical ventilation with a checklist aimed at the prevention of organ failure: protocol for a pragmatic stepped-wedged cluster trial of PROOFCheck

INTRODUCTION

Acute respiratory failure (ARF) often presents and progresses outside of the intensive care unit. However, recognition and treatment of acute critical illness is often delayed with inconsistent adherence to evidence-based care known to decrease the duration of mechanical ventilation (MV) and complications of critical illness. The goal of this trial is to determine whether the implementation of an electronic medical record-based early alert for progressive respiratory failure coupled with a checklist to promote early compliance to best practice in respiratory failure can improve the outcomes of patients at risk for prolonged respiratory failure and death.

METHODS AND ANALYSIS

A pragmatic stepped-wedged cluster clinical trial involving 6 hospitals is planned. The study will include adult hospitalised patients identified as high risk for MV >48 hours or death because they were mechanically ventilated outside of the operating room or they were identified as high risk for ARF on the Accurate Prediction of PROlonged VEntilation (APPROVE) score. Patients with advanced directives limiting intubation will be excluded. The intervention will consist of (1) automated identification and notification of clinician of high-risk patients by APPROVE or by invasive MV and (2) checklist of evidence-based practices in ARF (Prevention of Organ Failure Checklist-PROOFCheck). APPROVE and PROOFCheck will be developed in the pretrial period. Primary outcome is hospital mortality. Secondary outcomes include length of stay, ventilator and organ failure-free days and 6-month and 12-month mortality. Predefined subgroup analysis of patients with limitation of aggressive care after study entry is planned. Generalised estimating equations will be used to compare patients in the intervention phase with the control phase, adjusting for clustering within hospitals and time.

ETHICS AND DISSEMINATION

The study was approved by the institutional review boards. Results will be published in peer-reviewed journals and presented at international meetings.

TRIAL REGISTRATION NUMBER

NCT02488174.

Applying Rasch analysis to evaluate measurement equivalence of different administration formats of the Activity Limitation scale of the Cambridge Pulmonary Hypertension Outcome Review (CAMPHOR)

BACKGROUND

Electronic formats of patient-reported outcome (PRO) measures are now routinely used in clinical research studies. When changing from a validated paper and pen to electronic administration it is necessary to establish their equivalence. This study reports on the value of Rasch analysis in this process.

METHODS

Three groups of US pulmonary hypertension (PH) patients participated. The first completed an electronic version of the CAMPHOR Activity Limitation scale (e-sample) and this was compared with two pen and paper administrated samples (pp1 and pp2). The three databases were combined and analysed for fit to the Rasch model. Equivalence was evaluated by differential item functioning (DIF) analyses.

RESULTS

The three datasets were matched randomly in terms of sample size (n = 147). Mean age (years) and percentage of male respondents were as follows: e-sample (51.7, 16.0 %); pp1 (50.0, 14.0 %); pp2 (55.5, 40.4 %). The combined dataset achieved fit to the Rasch model. Two items showed evidence of borderline DIF. Further analyses showed the inclusion of these items had little impact on Rasch estimates indicating the DIF identified was unimportant.

CONCLUSIONS

Differences between the performance of the electronic and pen and paper administrations of the CAMPHOR Activity Limitation scale were minor. The results were successful in showing how the Rasch model can be used to determine the equivalence of alternative formats of PRO measures.

The structure and continuous stoichiometry change of 1DTbBrx@SWCNTs

HRTEM and HAADF STEM of 1DTbBrx@SWCNT meta-nanotubes reveal three structural modifications of 1D nanocrystals within single wall carbon nanotube channels attributed to a different stoichiometry of the guest crystal. For SWCNTs with diameters Dm > 1.4 nm a most complete tetragonal unit cell is observed. When crystallization occurs inside SWCNT with Dm < 1.4 nm 1D TbBrx crystal deforms a nanotube to elliptical shape in cross section. In this case the 1D crystal unit cell becomes monoclinic, with possible loss of a part of bromine atoms. Two modifications of a monoclinic unit cell appear. One of them is characterized by single or pair vacancies in the structure of the 1D crystal. Another structure is explained by peripheral and central bromine atoms loss. An appearance of such modifications can be stimulated by electron irradiation. The loss of bromine atoms is in agreement with chemical analysis data. Electronic properties of obtained meta-nanotubes are investigated using optical absorption and Raman spectroscopy. It is shown that intercalation of terbium bromide into SWCNTs leads to acceptor doping of SWCNTs. According to local EDX analysis and elemental mapping this doping can arise from significant stoichiometry change in 1D nanocrystal indicating an average Tb:Br atomic ratio of 1:2.8 ± 0.1.

Depression among adults with neurofibromatosis type 1: prevalence and impact on quality of life

Neurofibromatosis type 1 (NF1) carries a significant psychosocial burden for affected individuals. The objective of this study was to measure the prevalence of depressive symptoms among a large sample of adults with NF1 and to quantify the impact of depressive symptoms on quality of life (QoL). This cross-sectional study used an Internet-based questionnaire to collect data from 498 adults who self-reported as having NF1. Using the Center for Epidemiologic Studies Depression (CESD) scale, 55% of all participants (61% of females and 43% of males) scored above 16, indicating a high likelihood of clinical depression. In a multivariate regression model controlling for demographics and potential confounders, depressive symptoms accounted for 32% of the variance in QoL as measured by the Quality of Life Index. This study is the largest to date and found the highest prevalence of depression compared to prior studies. Our data provide more compelling evidence that individuals with NF1 are at increased risk for psychiatric morbidity and suggest that this population should be routinely screened for depression. Because depression was found to be strongly associated with QoL and accounted for nearly one-third of the variance in QoL, it is likely that effectively treating depression may significantly enhance QoL for individuals with NF1.

Increased leaf mesophyll porosity following transient retinoblastoma-related protein silencing is revealed by microcomputed tomography imaging and leads to a system-level physiological response to the altered cell division pattern

The causal relationship between cell division and growth in plants is complex. Although altered expression of cell-cycle genes frequently leads to altered organ growth, there are many examples where manipulation of the division machinery leads to a limited outcome at the level of organ form, despite changes in constituent cell size. One possibility, which has been under-explored, is that altered division patterns resulting from manipulation of cell-cycle gene expression alter the physiology of the organ, and that this has an effect on growth. We performed a series of experiments on retinoblastoma-related protein (RBR), a well characterized regulator of the cell cycle, to investigate the outcome of altered cell division on leaf physiology. Our approach involved combination of high-resolution microCT imaging and physiological analysis with a transient gene induction system, providing a powerful approach for the study of developmental physiology. Our investigation identifies a new role for RBR in mesophyll differentiation that affects tissue porosity and the distribution of air space within the leaf. The data demonstrate the importance of RBR in early leaf development and the extent to which physiology adapts to modified cellular architecture resulting from altered cell-cycle gene expression.

Primary Sjogren's syndrome: cognitive symptoms, mood, and cognitive performance

OBJECTIVE

To investigate the relationships between self-reported cognitive abilities, psychological symptoms and neuropsychological outcomes in PSS.

METHODS

Patients with Primary Sjogren's syndrome (PSS) and healthy controls completed a comprehensive neuropsychometric battery and questionnaires: the Centers for Epidemiological Scale-Depression, the Profile of Fatigue-mental domain (Prof-M) for cognitive symptoms, Fatigue Severity Scale, and the Short-Form McGill Pain Questionnaire.

RESULTS

Female patients with PSS (N = 39) were similar to controls (N = 17) in estimated premorbid intellectual function, age and education. Depression (P = 0.002), cognitive symptoms (P = 0.001), fatigue (P = 0.000003), and pain (P = 0.024) scores were greater in the patient group. Patients with PSS demonstrated inferior performance relative to controls in psychomotor processing (P = 0.027) and verbal reasoning (P = 0.007). Patients with PSS with and without depression had similar performance on multiple tests, but depressed patients had significantly lower scores for executive function (P = 0.041). Cognitive symptoms correlated with verbal memory (P = 0.048), whereas pain correlated with executive function measures (Stroop, P = 0.017) and working memory (Trails B, P = 0.036). In the regression model, depression and verbal memory were independent predictors that accounted for 61% of the variance in cognitive symptoms.

CONCLUSION

The Prof-M is a simple self-report measure which could be useful in screening PSS subjects who may benefit from detailed psychometric evaluation. Our results are consistent with the hypothesis that depression and verbal memory impairment are overlapping but independent aspects of neural involvement in PSS. While pain and depression are significant confounders of cognitive function in PSS, this study suggests that impaired verbal reasoning ability in PSS is not attributable to pain or depression.

The Crystallography of Metal Halides formed within Single Walled Carbon Nanotubes

The crystal growth behaviour and crystallography of a variety of metal halides incorporated within single walled carbon nanotubes (SWNTs) as determined by high resolution electron microscopy (HRTEM) is described. Simple packed structures, such as the alkali halides, form related structures within SWNTs that are found to be integral atomic layers in terms of their thickness as a function of the encapsulating SWNT diameter. An enhanced HRTEM image restoration technique reveals precise data concerning lattice distortions present in these crystals. More complex structures, such as those derived from 3D complex, layered and chain halides form related crystal structures within SWNTs. In narrow SWNTs (i.e. with diameters less than ca. 1.6 nm), structures consisting of individual 1D polyhedral chains (1D-PHCs) were obtained that were derived from the corresponding bulk halides structures. In the case of infinite 3D network and layered halides, the 1D polyhedral chains form with lower co-ordinations than in the bulk. Molecular halides also intercalate into SWNTs but these do not readily form organised structures within SWNTs.

Abstract P2-14-10: Self Reported Cognitive Function in Breast Cancer Survivors: A 12 Month Longitudinal Descriptive Study

Background: Changes in cognitive function are commonly reported in breast cancer (BC) survivors. Longitudinal studies have only recently been completed and are few. In particular, long term studies are lacking. The purpose of this abstract is to describe self-reported cognitive changes in women before the start, or after the first cycle of chemotherapy, through 12 months.

Methods: The data for this analysis were collected as part of a placebo-controlled randomized trial evaluating ginkgo biloba for the prevention of cognitive decline during adjuvant chemotherapy for BC. As there was no evidence that gingko biloba impacted cognitive function in any way, the sample was combined. Descriptive statistics were calculated to obtain the percent of women reporting worse perceived functioning or changes in their cognitive function at the start of chemotherapy, at the completion of treatment, and at 6, 12 and 24 months later (24 month data still being analyzed). 210 women, mostly white and mostly beginning anthracycline based chemotherapy, completed self report measures of cognition throughout the study. Women rated 10 areas of functioning by choosing a number from 1, signifying “functioning extremely less than normal”, to 7, signifying “extremely better than normal”. A score of 4 represented functioning perceived as “normal” for the respondent. Results: At baseline and after chemotherapy, the means for all 10 self reported cognitive items indicated “less than normal” functioning. Areas with the worst functioning included memory, ability to think clearly, staying focused, and planning ahead. At 6 and 12 months after chemotherapy, a percentage of participants reported worse functioning compared to baseline in every area. Changes in functioning are in the table below.

Table 1

At 12 months, the mean for only 4 items indicated these areas were at “normal” functioning. These were the ability to learn, solve problems, react quickly and balance a checkbook.

Discussion: For a subgroup of women, cognitive changes continue to worsen throughout 12 months and for many, perceived deficits remain.

Areas most negatively impacted relate to attention, memory and executive function. Future research should focus on identifying predictors of worse functioning and continued research is needed to elucidate targets for intervention research to prevent unwanted cognitive changes.

Zoledronic Acid for Treatment of Osteopenia and Osteoporosis in Women with Primary Breast Cancer (BC) Undergoing Adjuvant Aromatase Inhibitor (AI) Therapy

Background: Postmenopausal women with significant osteopenia/osteoporosis are at increased risk of fracture, a risk that is exacerbated by the use of Aromatase Inhibitors (AIs). Bisphosphonates may be used for these patients because there is no known interaction with estrogen and/or progesterone receptors (ER, PR). This study evaluated the concurrent use of zoledronic acid in patients with significant osteopenia or osteoporosis who received initial adjuvant letrozole therapy for primary BC, to determine if further bone mineral density (BMD) loss could be prevented.Methods: Postmenopausal women with Stage I-IIIa, ER and/or PR + BC, no evidence of metastatic disease, and a BMD T-score &lt; -2.0 were treated with daily letrozole 2.5 mg/d, vitamin D 400 international units/d, calcium 500 mg twice daily, and 4 mg I.V. zoledronic acid every 6 months (for 5 years). The BMD was measured at baseline and at one year. Kruskall-Wallis p-value methodology was used as the method of statistical analysis. Since this was a single-arm study, the analysis plan was primarily descriptive. The primary endpoint was the mean change in lumbar spine (LS) BMD at 1 year.Results: 60 patients were enrolled; 46 completed 1 year of treatment. Mean patient age was 67 years, with 44% having taken prior tamoxifen. At 1 year (see figure 1), LS BMD increased 2.66% (p=0.01), femoral neck (FN) BMD increased 4.81% (p=0.01), and any measured endpoint (within the LS or FN) increased 4.55% (p=0.0052). 7% of patients experienced a fracture vs.13% with a pre-existing history of fracture before enrollment. No patients had disease recurrence during year 1. Toxicity was minimal with arthralgia as the most common complaint. There were no reports of osteonecrosis of the jaw.Conclusion: Zoledronic acid prevents additional bone loss in postmenopausal women with significant osteopenia or osteoporosis initiating letrozole. Treatment with zoledronic acid was associated with an improvement in BMD.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 2103.

Hydroxocobalamin dose escalation improves metabolic control in cblC

Cobalamin C (cblC), a combined form of methylmalonic acidaemia and hyperhomocysteinaemia, is recognized as the most frequent inborn error of intracellular cobalamin metabolism. This condition can be detected by expanded newborn screening and can have an acute neonatal presentation that is life-threatening if not suspected and promptly treated. Intramuscular (IM) hydroxocobalamin (OHCbl) is the main treatment for patients with cblC, but formal dosing guidelines do not exist. A clinical improvement and a decrease of plasma methylmalonic acid (MMA) and total homocysteine (tHcy) levels, and an increase in methionine are typically observed after its initiation. It is well recognized that despite treatment, long-term complications such as developmental delay and progressive visual loss, may still develop. We describe the biochemical response of a 13-year-old boy with worsening metabolic parameters despite strict adherence to a conventional treatment regimen. We progressively increased the OHCbl dose from 1 to 20 mg IM per day and observed a dose-dependent response with an 80% reduction of plasma MMA (25 to 5.14 micromol/L; normal range <0.27 micromol/L), a 55% reduction of tHcy (112 to 50 micromol/L; normal range: 0-13 micromol/L) and a greater than twofold increase in methionine (17 to 36 micromol/L; normal range: 7-47 micromol/L). This suggests that higher OHCbl doses might be required to achieve an optimal biochemical response in cblC patients, but it is unknown whether it may slow or eliminate other complications. Future clinical trials to determine the benefits of higher-dose OHCbl therapy in patients with cblC and other disorders of intracellular cobalamin metabolism should be planned.

Effect of a pathway bundle on length of stay

BACKGROUND

Pathways to guide clinical care are well accepted and used in many emergency departments. We wanted to introduce a number ("bundle") over a short space of time and involve the whole patient stay in the pathway. It was hypothesised that a more efficient process would result with an overall reduction in length of stay (LoS).

METHODS

A "bundle" of 14 evidence-based pathways of care was introduced into a medium-sized district general hospital (DGH) in late 2006/early 2007. These pathways covered emergency department care and acute medical care for a period of up to 48 h. A total of 8184 acute emergency admission episodes were audited, 3852 in the 8 months before introduction of the new pathways and 4332 in the 8 months after their introduction.

RESULTS

The overall effect of introducing the pathway bundle had a trend towards reduction in LoS by 0.2 days (95% CI -0.2 to 0.5), but this was not statistically significant (p>0.1). However, in those patients with </=2 diagnoses, the introduction of the pathway bundle had an independent effect in reducing LoS by 0.4 days (95% CI 0.04 to 0.7, p<0.01). In patients with </=2 diagnoses (63.0% of all pre-pathway cases and 63.4% of all post-pathway cases), the reduction in LoS equates to a saving of 2154 (CI 215 to 3769) bed days per annum or 5.9 (CI 0.6 to 10.3) beds saved each day. This reduced LoS represents an improvement of 2.5% (CI 0.25% to 4.38%) in medical bed usage. As this benefit occurs in the uncomplicated group of patients without multiple co-morbidities, such pathways would have the most effect in the type of patients who may be looked after by an emergency or acute physician. They are much less likely to be effective in those who require specialist intervention due to a more complicated presentation and possibly those with multiple co-morbidities.

CONCLUSION

The introduction of a bundle of evidence-based care pathways can modestly reduce LoS for certain types of acute medical patients in a DGH setting.

Soft tissue injuries: 7 Shoulder and elbow

A description of soft tissue injuries to the shoulder and elbow, together with assessment, imaging and treatment considerations.

Baseline quality of life as a prognostic factor for overall survival in lung cancer patients

e19031

Background: Useful predictors of survival in cancer patients have been found including such as gender, race, age, marital status, state of disease and tumor location. We set to explore the prognostic value of baseline QOL assessments on overall survival in lung cancer patients. Methods: A total of 1,319 lung cancer patients were followed at Mayo Clinic between 1997 and 2007. Overall QOL was assessed by either Lung Cancer Symptom Scale (LCSS) or a single-item Linear Analogue Self Assessment (LASA) with comparable wording. QOL scores were transformed to a 0–100 scale with higher scores representing better status. Patients QOL scores assessed within the first 6 months of follow-up were dichotomized using a priori definition for clinically deficiency score (CDS, ≤50 vs. >50). The Kaplan-Meier method was used to estimate the distribution of survival times by QOL clinical deficient categorization. Cox Proportional Hazards Models were used to evaluate the prognostic importance of QOL on OS alone and in the presence of age, smoking category, gender, treatment, stage of disease, smoking cessation and years of consuming a pack every day. Results: Baseline QOL was significantly associated with OS univariately (HR=0.46 with p<0.0001 based on the CDS categorization). After controlling for all these other factors, the indication of a clinically deficient baseline QOL contributed significantly to the prediction of patient survival (p=0.0002; HR=0.67). Age, treatment, disease stage, smoking cessation and smoking category were also significant predictors of OS multivariately. The median survival for patients that had an overall QOL score less than the CDS (≤50) was 1.6 versus 4.6 years for patients with QOL >50. Conclusions: Baseline overall QOL measured by LCSS or LASA is a significant and independent prognostic factor for OS in lung cancer patients. A meaningful next step in this research is to investigate interventions to improve lung cancer patient QOL and thereby increase their likelihood of survival as well.

No significant financial relationships to disclose.

Enamel defects and salivary methylmalonate in methylmalonic acidemia

INTRODUCTION AND OBJECTIVE

To characterize enamel defects in patients with methylmalonic acidemia (MMA) and cobalamin (cbl) metabolic disorders and to examine salivary methylmalonate levels in MMA.

SUBJECTS AND METHODS

Teeth from patients (n = 32) were evaluated for enamel defects and compared with age- and gender-matched controls (n = 55). Complementation class (mut, cblA, cblB and cblC) and serum methylmalonate levels were examined. Primary teeth from two patients were examined by light and scanning electron microscopy and salivary methylmalonate levels from two patients were analyzed.

RESULTS

Enamel defects were significantly more prevalent per tooth in the affected group than the control group, across complementation types (P < 0.0001). The mut MMA subgroup had a significantly higher prevalence per individual of severe enamel defects than controls (P = 0.021), and those with enamel defects exhibited higher serum methylmalonate levels than those without (P = 0.017). Salivary methylmalonate levels were extremely elevated and were significantly higher than controls (P = 0.002). Primary teeth were free of enamel defects except for two cblC patients who exhibited severe enamel hypoplasia. One primary tooth from a cblC patient manifested markedly altered crystal microstructure.

CONCLUSION

Enamel anomalies represent a phenotypic manifestation of MMA and cbl metabolic disorders. These findings suggest an association between enamel developmental pathology and disordered metabolism.

Levetiracetam for the treatment of hot flashes: A pilot study

9116

Background: Hot flashes affect 75 % to 90 % of women transitioning to menopause and are a major cause of morbidity among breast cancer survivors. Levetiracetam, a popular anticonvulsant, is a centrally active agent that anecdotally appeared to reduce hot flashes in clinical practice. This phase II trial sought to evaluate the efficacy of levetiracetam in reducing hot flashes among women with a history of breast cancer or women who did not wish to take estrogen therapy for fear of an increased risk of breast cancer. Methods: Women who were experiencing bothersome hot flashes (≥ 14 times per week, for ≥ 1 month) were eligible. A single arm pilot study design based on previous work was used with a planned sample size of 30 patients. The patients did not receive any study medication during the first week (baseline week). At the beginning of the second week, patients were started on levetiracetam (500 mg), and were to increase the dose by 500 mg each week to a goal of 1,000 mg twice daily. Hot flash diaries were completed daily. The primary endpoint was hot flash score (frequency times average severity). The change from week 1 (baseline) to week 5, the last treatment week, was analyzed by paired t-test and related Wilcoxon procedures. Results: A total of 30 women were enrolled onto this study in eight months. All patients were eligible. 19 women completed all 4 weeks of the study treatment and provided complete data. After treatment with levetiracetam for 4 weeks, mean hot flash scores were reduced by 57% (95% CI 39%-75%), while mean hot flash frequencies were reduced by 53% (95% CI 38%-68%), reductions being greater than what would be expected with a placebo. There were significant improvements, compared to baseline week data, in sweating, hot flash distress, and satisfaction with hot flash control. Eight subjects stopped the study drug due to treatment related adverse events (grade I/II), with the most frequently reported being somnolence, fatigue and dizziness. Conclusions: While levetiracetam appears to be a promising therapy for the treatment of hot flashes, further study is needed to better substantiate the toxicity and efficacy of this drug before it can be more definitively recommended for use in clinical practice.

No significant financial relationships to disclose.

A pilot, multi-dose, placebo-controlled evaluation of american ginseng (panax quinquefolius) to improve cancer-related fatigue: NCCTG trial N03CA

9001

Background: Fatigue is one of the most common symptoms in people diagnosed with cancer. Ginseng is a popular herb for treatment of this. It has been termed an “adaptogen”, felt to be able to restore balance to the body; its potential anti-fatigue efficacy is supported by animal data. The purpose of this pilot trial was to evaluate three doses of American Ginseng versus placebo for cancer-related fatigue. Methods: Patients with a life expectancy = 6 months and a history of cancer-related fatigue who had been experiencing fatigue = 1 month were eligible. Exclusion criteria included prior use of ginseng, chronic systemic steroids and brain malignancies. Other etiologies for fatigue, such as pain, were also excluded. Participants were randomized to receive, in a double blind manner, placebo, 750 mg/d, 1,000 mg/d or 2,000 mg/d of American Ginseng in BID dosing for 8 weeks. Endpoints included The Brief Fatigue Inventory (BFI), the Vitality Subscale of the SF-36 and several numeric analogue questions of perceived benefit; endpoints were measured at baseline, 4 weeks and 8 weeks. Area under the curve (AUC) and change from baseline were calculated. Results: Two hundred eighty two patients (69–72 per arm) were enrolled from 10/21/2005 to 07/05/2006. Available 8-week data are provided in the table below; higher numbers are better. There were no statistically significant differences in any grade of toxicity between active and placebo arms, and an equivalent number of patients discontinued the study due to adverse events in each arm. Conclusion: This randomized pilot trial provided data to suggest that American Ginseng doses of 1000–2000 mg/d may be effective for alleviating cancer related fatigue. Therefore, further study of American Ginseng in cancer survivors appears warranted.

No significant financial relationships to disclose.

[Table: see text]

Transdermal testosterone in female cancer survivors with decreased libido

8507

Background: Problems with sexual functioning are an issue negatively affecting the quality of life of female cancer survivors. Testosterone has been implicated as an important hormone in sexual functioning such as libido. Studies of transdermal testosterone have shown benefit in enhancing libido in women who have been diagnosed with hypoactive sexual desire disorder after bilateral oophorectomy. This phase III placebo-controlled clinical trial evaluated whether transdermal testosterone would increase libido in female cancer survivors. Methods: Women with a history of cancer, currently without evidence of disease, were eligible if they reported a decrease in sexual desire and had a sexual partner. Women must have been postmenopausal. Eligible women were randomized to receive 2% testosterone in Vanicream (10 mg daily) versus placebo Vanicream for four weeks, then crossed over to the opposite treatment. The primary endpoint, libido, was measured via the desire subscales of the Changes in Sexual Functioning Questionnaire (CSFQ), which were completed at baseline and at the end of 4 and 8 weeks of treatment. The primary endpoint was the average intra-patient change from baseline to four weeks in the CSFQ subscales between the two arms. A total of 64 patients per group were needed to provide 80% power to detect a difference of 8 units between the treatment means. Two-sided alternative hypothesis testing and a 5% Type I error rate were used. Results: One hundred fifty women were enrolled onto this study. Complete data were available for 132 women. For those on active testosterone cream, serum bioavailable testosterone levels increased significantly over placebo, with a mean change from baseline of 12 and 10 ng/dl for the first and second period, respectively (p<.0001). The average intra-patient change from baseline to week 4 in libido was 5.5 on testosterone and 4.4 on placebo (p=0.58). No carryover effect was detected. The difference in average intra-patient changes from baseline for the entire crossover design between the two arms was only 1.1 points (95% confidence interval of -1.2 to 3.4, p=0.35). Conclusion: Testosterone is not a panacea for libido troubles in women with a history of cancer. Further studies are needed to determine whether there is a role for transdermal testosterone in this population.

No significant financial relationships to disclose.