ID: 63: RAPID 3D PRECLINICAL QUANTITATIVE LUNG IMAGING WITH ULTRASHORT-ECHO TIME (UTE) MRI IN A MOUSE MODEL OF CYSTIC FIBROSIS LUNG DISEASE

Currently, the life expectancy for cystic fibrosis (CF) lung disease is less than 40 years due to decreasing lung function despite significant advances in the care and treatment of these patients. As patients live longer, the preservation of healthy lung tissue becomes of paramount importance to improve patient quality of life and increase life span. To do this, an understanding of the early disease processes is needed as is an ability to monitor the efficacy of therapeutic interventions early in life. CF lung disease, similar to other lung diseases, is a regional disease causing local dysfunction in the lung tissue and changes in lung anatomy. It is important for any monitoring or diagnostic tool to be sensitive to early regional disease which current methods (spirometry) are not. This lack of sensitivity to regional disease limits the ability of physicians and researchers to track the earliest stages of disease and assess treatment efficacy in these initial disease stages, ideally in infants and young children. Three dimensional imaging presents a unique solution to this problem by providing a non-invasive, volumetric investigation of the lung tissue. Computed tomography has long been the first choice in clinical lung imaging offering excellent resolution and fast imaging times but results in repeated exposure to ionizing radiation. Because the patient populations of interest are infants and children, avoidance of unnecessary, repeated radiation exposure during longitudinal monitoring is desirable. This combination of clinical and research need has led us to the exploration of rapid MRI techniques for lung imaging. We are interested in developing a novel, robust quantitative Magnetic Resonance Imaging technique that allows for 3D investigation of the lung tissue and is sensitive to early disease changes. Our hypothesis is that quantitative imaging will be able to detect changes in regional lung anatomy as an indication of early disease before disease is detected by standard methods. To accomplish this goal, we are proposing the implementation of multiple advanced quantitative MRI techniques including T1-mapping using Saturation-Recovery Look-Locker mapping and simultaneous multiple parameter mapping (combinations of T1, T2, T2*) using the recently developed Magnetic Resonance Fingerprinting method. An ultra-short echo time acquisition will be used to ensure imaging of the rapidly decaying MRI signal in the lung is possible. Using a radial acquisition, we plan to include an undersampled acquisition to reduce imaging time and generate an imaging method that is rapid and insensitive to patient motion. Our goal is to initially apply these quantitative measures in a mouse model of cystic fibrosis to establish the ability of the imaging methods to be sensitive to regional disease in CF mice. We expect to see changes in the quantitative parameters in areas that correspond to diseased areas of the lung upon histological investigation. These quantitative measurements should give unambiguous indications of disease and allow identification of changes in lung anatomy early in the disease process. This work will lay the foundation for translation of clinical CF monitoring in a pediatric population. Translational studies such as these will hopefully provide a measurement of disease progression and provide a new opportunity to evaluate early disease therapeutics offering insight into the earliest manifestations of CF lung disease.

Does a research article's country of origin affect perception of its quality and relevance? A national trial of US public health researchers

OBJECTIVES

The source of research may influence one's interpretation of it in either negative or positive ways, however, there are no robust experiments to determine how source impacts on one's judgment of the research article. We determine the impact of source on respondents' assessment of the quality and relevance of selected research abstracts.

DESIGN

Web-based survey design using four healthcare research abstracts previously published and included in Cochrane Reviews.

SETTING

All Council on the Education of Public Health-accredited Schools and Programmes of Public Health in the USA.

PARTICIPANTS

899 core faculty members (full, associate and assistant professors)

INTERVENTION

Each of the four abstracts appeared with a high-income source half of the time, and low-income source half of the time. Participants each reviewed the same four abstracts, but were randomly allocated to receive two abstracts with high-income source, and two abstracts with low-income source, allowing for within-abstract comparison of quality and relevance

PRIMARY OUTCOME MEASURES

Within-abstract comparison of participants' rating scores on two measures--strength of the evidence, and likelihood of referral to a peer (1-10 rating scale). OR was calculated using a generalised ordered logit model adjusting for sociodemographic covariates.

RESULTS

Participants who received high income country source abstracts were equal in all known characteristics to the participants who received the abstracts with low income country sources. For one of the four abstracts (a randomised, controlled trial of a pharmaceutical intervention), likelihood of referral to a peer was greater if the source was a high income country (OR 1.28, 1.02 to 1.62, p<0.05).

CONCLUSIONS

All things being equal, in one of the four abstracts, the respondents were influenced by a high-income source in their rating of research abstracts. More research may be needed to explore how the origin of a research article may lead to stereotype activation and application in research evaluation.

The perturbation paradigm modulates error-based learning in a highly automated task: outcomes in swallowing kinematics

Traditional motor learning studies focus on highly goal-oriented, volitional tasks that often do not readily generalize to real-world movements. The goal of this study was to investigate how different perturbation paradigms alter error-based learning outcomes in a highly automated task. Swallowing was perturbed with neck surface electrical stimulation that opposes hyo-laryngeal elevation in 25 healthy adults (30 swallows: 10 preperturbation, 10 perturbation, and 10 postperturbation). The four study conditions were gradual-masked, gradual-unmasked, abrupt-masked, and abrupt-unmasked. Gradual perturbations increasingly intensified overtime, while abrupt perturbations were sustained at the same high intensity. The masked conditions reduced cues about the presence/absence of the perturbation (pre- and postperturbation periods had low stimulation), but unmasked conditions did not (pre- and postperturbation periods had no stimulation). Only hyo-laryngeal range of motion measures had significant outcomes; no timing measure demonstrated learning. Systematic-error reduction occurred only during the abrupt-masked and abrupt-unmasked perturbations. Only the abrupt-masked perturbation caused aftereffects. In this highly automated task, gradual perturbations did not induce learning similarly to findings of some volitional, goal-oriented adaptation task studies. Furthermore, our subtle and brief adjustment of the stimulation paradigm (masked vs. unmasked) determined whether aftereffects were present. This suggests that, in the unmasked group, sensory predictions of a motor plan were quickly and efficiently modified to disengage error-based learning behaviors.

Neonatal intensive care unit to home: the transition from parent and pediatrician perspectives, a prospective cohort study

OBJECTIVES

To describe the experience of a low-income population during the transition from the neonatal intensive care unit (NICU) to home and to compare these experiences with pediatrician perspectives.

STUDY DESIGN

A prospective cohort study in a Level III, 40-bed NICU at a county hospital in Northern California affiliated with seven outpatient pediatric clinics. We surveyed parents in English or Spanish at discharge (n=79) and two weeks after discharge (n=49), along with outpatient pediatricians (n=17). Parents assessed experiences with discharge and the frequency with which barriers were encountered after discharge. We compared parent experiences with pediatrician estimates on four of these barriers.

RESULT

Spanish survey participants had more difficulty finding a NICU doctor (P=0.05) or nurse (P=0.001) to answer their questions. After discharge, 16% of families experienced significant challenges with two or more barriers. In contrast, the majority of pediatricians estimated that 50% or more families had significant challenges with all four barriers.

CONCLUSION

Communication difficulties were the most commonly reported barriers during the NICU stay and physicians overestimated the frequency that families experienced challenges after discharge. Parent input is important to create effective interventions aimed at improving care and limiting disparities.

Thrombocytopenia in Patients with Gastric Varices and the Effect of Balloon-occluded Retrograde Transvenous Obliteration on the Platelet Count

OBJECTIVES

Gastric varices primarily occur in cirrhotic patients with portal hypertension and splenomegaly and thus are probably associated with thrombocytopenia. However, the prevalence and severity of thrombocytopenia are unknown in this clinical setting. Moreover, one-third of patients after balloon-occluded retrograde transvenous obliteration (BRTO) have aggravated splenomegaly, which potentially may cause worsening thrombocytopenia. The aim of the study is to determine the prevalence and degree of thrombocytopenia in patients with gastric varices associated with gastrorenal shunts undergoing BRTO, to determine the prognostic factors of survival after BRTO (platelet count included), and to assess the effect of BRTO on platelet count over a 1-year period.

MATERIALS AND METHODS

This is a retrospective review of 35 patients who underwent BRTO (March 2008-August 2011). Pre- and post-BRTO platelet counts were noted. Potential predictors of bleeding and survival (age, gender, liver disease etiology, platelet count, model for end stage liver disease [MELD]-score, presence of ascites or hepatocellular carcinoma) were analyzed (multivariate analysis). A total of 91% (n = 32/35) of patients had thrombocytopenia (<150,000 platelet/cm(3)) pre-BRTO. Platelet counts at within 48-h, within 2 weeks and at 30-60 days intervals (up to 6 months) after BRTO were compared with the baseline pre-BRTO values.

RESULTS

35 Patients with adequate platelet follow-up were found. A total of 92% and 17% of patients had a platelet count of <150,000/cm(3) and <50,000/cm(3), respectively. There was a trend for transient worsening of thrombocytopenia immediately (<48 h) after BRTO, however, this was not statistically significant. Platelet count was not a predictor of post-BRTO rebleeding or patient survival. However, MELD-score, albumin, international normalized ratio (INR), and etiology were predictors of rebleeding.

CONCLUSION

Thrombocytopenia is very common (>90% of patients) in patients undergoing BRTO. However, BRTO (with occlusion of the gastrorenal shunt) has little effect on the platelet count. Long-term outcomes of BRTO for bleeding gastric varices using sodium tetradecyl sulfate in the USA are impressive with a 4-year variceal rebleed rate and transplant-free survival rate of 9% and 76%, respectively. Platelet count is not a predictor of higher rebleeding or patient survival after BRTO.

An exploratory investigation amongst Australian mothers regarding pharmacies and opportunities for nutrition promotion

The early years life-stage (1 year either side of childbirth) is an important period for preventive action focusing on optimizing nutritional health for mothers and babies. Community pharmacy is a much utilized, easily accessed setting for health promotion and exposure to the primary health care system. The literature suggests that there has been limited exploration of pharmacy utilization by mothers, particularly in the context of nutrition focused health promotion. This study aimed to explore mothers' expectations and experiences of pharmacy based health care and to explore mothers' attitudes and opinions regarding opportunities and scope for nutrition-related health promotion in pharmacy. Qualitative semi-structured telephone interviews were conducted amongst a purposive sample of 28 mothers from across Queensland, Australia. Interviews were transcribed and analysed thematically using an iterative approach. Participants as relatively frequent users of pharmacy services accessed pharmacy for medicines or product related concerns but expected information and health advice to be available. Opportunities for nutrition promotion in pharmacy, identified by participants, related primarily to addressing their personal needs for information, advice and support during this life-stage. Improving and reorienting pharmacy staff practices may contribute to more supportive guidance being provided to mothers in this setting.