MR-based cardiac and respiratory motion correction of PET: application to static and dynamic cardiac 18F-FDG imaging.

Motion of the myocardium deteriorates the quality and quantitative accuracy of cardiac PET images. We present a method for MR-based cardiac and respiratory motion correction of cardiac PET data and evaluate its impact on estimation of activity and kinetic parameters in human subjects. Three healthy subjects underwent simultaneous dynamic 18F-FDG PET and MRI on a hybrid PET/MR scanner. A cardiorespiratory motion field was determined for each subject using navigator, tagging and golden-angle radial MR acquisitions. Acquired coincidence events were binned into cardiac and respiratory phases using electrocardiogram and list mode-driven signals, respectively. Dynamic PET images were reconstructed with MR-based motion correction (MC) and without motion correction (NMC). Parametric images of 18F-FDG consumption rates (Ki) were estimated using Patlak's method for both MC and NMC images. MC alleviated motion artifacts in PET images, resulting in improved spatial resolution, improved recovery of activity in the myocardium wall and reduced spillover from the myocardium to the left ventricle cavity. Significantly higher myocardium contrast-to-noise ratio and lower apparent wall thickness were obtained in MC versus NMC images. Likewise, parametric images of Ki calculated with MC data had improved spatial resolution as compared to those obtained with NMC. Consistent with an increase in reconstructed activity concentration in the frames used during kinetic analyses, MC led to the estimation of higher Ki values almost everywhere in the myocardium, with up to 18% increase (mean across subjects) in the septum as compared to NMC. This study shows that MR-based motion correction of cardiac PET results in improved image quality that can benefit both static and dynamic studies.

How long do I have? Observational study on communication about life expectancy with advanced cancer patients.

OBJECTIVE: To examine how communication about life expectancy is initiated in consultations about palliative chemotherapy, and what prognostic information is presented. METHODS: Patients with advanced cancer (n=41) with a median life expectancy <1year and oncologists (n=6) and oncologists-in-training (n=7) meeting with them in consultations (n=62) to discuss palliative chemotherapy were included. Verbatim transcripts of audio-recorded consultations were analyzed using MAXqda10. RESULTS: Life expectancy was addressed in 19 of 62 of the consultations. In all cases, patients took the initiative, most often through direct questions. Estimates were provided in 12 consultations in various formats: the likelihood of experiencing a significant event, point estimates or general time scales of "months to years", often with an emphasis on the "years". The indeterminacy of estimates was consistently stressed. Also their potential inadequacy was regularly addressed, often by describing beneficial prognostic predictors for the specific patient. Oncologists did not address the reliability or precision of estimates. CONCLUSION: Oncologists did not initiate talk about life expectancy, they used different formats, emphasized the positive and stressed unpredictability, yet not ambiguity of estimates. PRACTICE IMPLICATIONS: Prognostic communication should be part of the medical curriculum. Further research should address the effect of different formats of information provision.

PUGS: A novel scale to assess perceptions of uncertainties in genome sequencing.

Expectations of results from genome sequencing by end users are influenced by perceptions of uncertainty. This study aimed to assess uncertainties about sequencing by developing, evaluating, and implementing a novel scale. The Perceptions of Uncertainties in Genome Sequencing (PUGS) scale comprised ten items to assess uncertainties within three domains: clinical, affective, and evaluative. Participants (n=535) from the ClinSeq® NIH sequencing study completed a baseline survey that included the PUGS; responses (mean = 3.4/5, SD=0.58) suggested modest perceptions of certainty. A confirmatory factor analysis identified factor loadings that led to elimination of two items. A revised eight-item PUGS scale was used to test correlations with perceived ambiguity (r = -0.303, p < 0.001), attitudinal ambivalence (r = -0.111, p = 0.011), and ambiguity aversion (r = -0.093, p = 0.033). Results support nomological validity. A correlation with the MICRA uncertainty subscale was found among 175 cohort participants who had received results (r = -0.335, p < 0.001). Convergent and discriminant validity were also satisfied in a second sample of 208 parents from the HudsonAlpha CSER Project who completed the PUGS (mean = 3.4/5, SD = 0.72), and configural invariance was supported across the two datasets. As such, the PUGS is a promising scale for evaluating perceived uncertainties in genome sequencing, which can inform interventions to help patients form realistic expectations of these uncertainties.

Health literacy and pap testing in insured women.

Several studies have found a link between health literacy and participation in cancer screening. Most, however, have relied on self-report to determine screening status. Further, until now, health literacy measures have assessed print literacy only. The purpose of this study was to examine the relationship between participation in cervical cancer screening (Papanicolaou [Pap] testing) and two forms of health literacy-reading and listening. A demographically diverse sample was recruited from a pool of insured women in Georgia, Massachusetts, Hawaii, and Colorado between June 2009 and April 2010. Health literacy was assessed using the Cancer Message Literacy Test-Listening and the Cancer Message Literacy Test-Reading. Adherence to cervical cancer screening was ascertained through electronic administrative data on Pap test utilization. The relationship between health literacy and adherence to evidence-based recommendations for Pap testing was examined using multivariate logistic regression models. Data from 527 women aged 40 to 65 were analyzed and are reported here. Of these 527 women, 397 (75 %) were up to date with Pap testing. Higher health literacy scores for listening but not reading predicted being up to date. The fact that health literacy listening was associated with screening behavior even in this insured population suggests that it has independent effects beyond those of access to care. Patients who have difficulty understanding spoken recommendations about cancer screening may be at risk for underutilizing screening as a result.

The short-term outcome of laser endoureterotomy for ureteric stricture.

With the advent of new technology, the treatment for ureteric stricture has moved from open surgery to endoscopic procedures. Our goals were to review and determine the prognostic factors for success of laser endoureterotomy for ureteric stricture. This is a cross sectional study for all cases that underwent laser endoureterotomy in a single centre from 2002 to 2009. Standard treatment in this centre utilizes holmium laser. The fiber used was 365nm, setting as 1J and frequency 8 Hz; power output 8 W. Confirmation of adequacy of incision wss by either visualization of extra-ureteric fat or extravasations of contrast on fluoroscopic imaging. Success or recurrence of the endoureterotomy was confirmed objectively with evidence of improvement from imaging. Of these 77 patients, 42 cases (61.8%) of the strictures were from upper ureter. Eight cases (11.7%) of mid-ureteric while lower ureter had 18 cases (26.5%). Length of stricture has been grouped into two groups; Short (<1cm) and long (≥1cm) and their distributions were 47.1% and 26.5% respectively. Follow-up duration ranged from six months to 88 months with an average of 19.6 months. Success rate was 76.5% (52 patients) while 16 patients (23.5%) developed recurrence. Stone disease, positive presenting symptoms and short length of the stricture were identified as variables with good predictor. This study achieved a 76.5% of success rate for this treatment modality for benign ureteric stricture in wellselected patients. Success is more likely if patient is symptomatic (earlier treatment) and previous stone disease present as a risk factor.

Hypoxia-specific GM-CSF-overexpressing neural stem cells improve graft survival and functional recovery in spinal cord injury.

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a hematopoietic cytokine that stimulates the differentiation and function of hematopoietic cells. GM-CSF has been implicated in nervous system function. The goal of the present study was to understand the effects of hypoxia-induced GM-CSF on neural stem cells (NSCs) in a model of spinal cord injury (SCI). GM-CSF-overexpressing NSCs were engineered utilizing a hypoxia-inducible gene expression plasmid, including an Epo enhancer ahead of an SV promoter (EpoSV-GM-CSF). Cells were then subjected to hypoxia (pO(2), 1%) or a hypoxia-mimicking reagent (CoCl(2)) in vitro. The progression of time of GM-CSF expression was tracked in EpoSV-GM-CSF-transfected NSCs. Overexpression of GM-CSF in undifferentiated and differentiated NSCs created resistance to H(2)O(2)-induced apoptosis in hypoxia. NSCs transfected with EpoSV-GM-CSF or SV-GM-CSF were transplanted into rats after SCI to assess the effect of GM-CSF on NSC survival and restoration of function. Moreover, a significantly higher amount of surviving NSCs and neuronal differentiation was observed in the EpoSV-GM-CSF-treated group. Significant improvement in locomotor function was also found in this group. Thus, GM-CSF overexpression by the Epo enhancer in hypoxia was beneficial to transplanted NSC survival and to behavioral improvement, pointing toward a possible role for GM-CSF in the treatment of SCI.

Historical changes in the objectives of the periodic health examination.

Important historical changes have occurred both in the content of the periodic health examination and in the legitimacy with which this examination has been viewed. These changes reflect fundamental shifts in the objectives of the examination and in the concerns of its advocates, the most prominent of whom have been physicians; leaders in the life insurance, private corporate, and prepaid health care industries; and medical expert panels. The shifting dominance of concerns has driven the development of the periodic health examination, and continual reassessment of the value and limitations of the examination is warranted.

Cultural factors associated with health-risk behavior among the Cheyenne River Sioux.

A field study was conducted to identify cultural factors--values, beliefs, and related characteristics--associated with health-risk behavior among adult members of the Cheyenne River Sioux Tribe. The Cultural Values Survey (CVS), an instrument for measuring cultural values and related characteristics, was developed and pilot tested in the study population. This instrument, along with the Health Risk Appraisal (HRA) (an instrument developed by the Centers for Disease Control to quantify major health-related behaviors), was administered to a random sample of 429 adults in the study community. Significant differences between females and males for both cultural characteristics and health-risk behaviors were found. Females had significantly higher HRA-calculated Health Index values than males, reflecting overall healthier behaviors. Females who scored higher on cultural factors consistent with more traditional Lakota Indian lifestyles (e.g., degree of Indian blood, Lakota language spoken in the home, traditional Lakota beliefs) had higher HRA Health Index values than females scoring lower in these characteristics. Males who scored higher in factors related to self-determination (e.g., hard work, personal control, industriousness, individual action) had higher Health Index values than those who scored lower in these areas. Further testing of the CVS instrument, as well as further research from both epidemiologic and social science perspectives is essential to elucidate the nature of the relationship between cultural factors and health-related behavior.