The NICHD Women's Contraceptive and Reproductive Experiences Study: methods and operational results

PURPOSE: This paper presents methods and operational results of a population-based case-control study examining the effects of oral contraceptive use on breast cancer risk among white and black women aged 35-64 years in five U.S. locations. METHODS: Cases were women newly diagnosed with breast cancer during July 1994 through April 1998. Controls were identified through random digit dialing (RDD) using unclustered sampling with automated elimination of nonworking numbers. Sampling was density-based, with oversampling of black women. In-person interviews were conducted from August 1994 through December 1998. Blood samples were obtained from subsets of cases and controls, and tissue samples were obtained from subsets of cases. A computerized system tracked subjects through study activities. Special attention was devoted to minimizing exposure misclassification, because any exposure-disease associations were expected to be small. RESULTS: An estimated 82% of households were screened successfully through RDD. Interviews were completed for 4575 cases (2953 whites; 1622 blacks) and 4682 controls (3021 whites; 1661 blacks). Interview response rates for cases and controls were 76.5% and 78.6%, respectively, with lower rates for black women and older women. CONCLUSIONS: The methodologic details of this large collaboration may assist researchers conducting similar investigations.     

Predicting the development of mild cognitive impairment: a new use of pattern recognition

While the conversion from mild cognitive impairment to Alzheimer's disease has received much recent attention, the transition from normal cognition to mild cognitive impairment is largely unexplored. The present pattern recognition study addressed this by using neuropsychological test scores and neuroimaging morphological measures to predict the later development of mild cognitive impairment in cognitively normal community-dwelling individuals aged 70-90years. A feature selection algorithm chose a subset of neuropsychological and FreeSurfer-derived morphometric features that optimally differentiated between individuals who developed mild cognitive impairment and individuals who remained cognitively normal. Support vector machines were used to train classifiers and test prediction performance, which was evaluated via 10-fold cross-validation to reduce variability. Prediction performance was greater when using a combination of neuropsychological scores and morphological measures than when using either of these alone. Results for the combined method were: accuracy 78.51%, sensitivity 73.33%, specificity 79.75%, and an area under the receiver operating characteristic curve of 0.841. Of all the features investigated, memory performance and measures of the prefrontal cortex and parietal lobe were the most discriminative. Our prediction method offers the potential to detect elderly individuals with apparently normal cognition at risk of imminent cognitive decline. Identification at this stage will facilitate the early start of interventions designed to prevent or slow the development of Alzheimer's disease and other dementias.     

Gender differences in brain activation on a mental rotation task

ABSTRACT Few neuroimaging studies have explored gender differences on mental rotation tasks. Most studies have utilized samples with both genders, samples mainly consisting of men, or samples with six or fewer females. Graduate students in science fields or liberal arts programs (20 males, 20 females) completed a mental rotation task during functional magnetic resonance imaging (fMRI). When a pair of cube figures was shown, the participant made a keypad response based on whether the pair is the same/similar or different. Regardless of gender, the bilateral middle frontal gyrus, bilateral intraparietal sulcus (IPS), and the left precuneus were activated when a subject tried to solve the mental rotation task. Increased activation in the right inferior frontal gyrus/middle frontal gyrus, the left precuneus/posterior cingulate cortex/cuneus region, and the left middle occipital gyrus was found for men as compared to women. Better accuracy and shorter response times were correlated with an increased activation in the bilateral intraparietal sulcus. No significant brain activity differences related to mental rotation were found between academic majors. These findings suggest that networks involved in visual attention appear to be more strongly activated in the mental rotation tasks in men as compared to women. It also suggests that men use a more automatic process when analyzing complex visual reasoning tasks while women use a more top-down process.     

An interactive model of anxiety sensitivity relevant to suicide attempt history and future suicidal ideation

Recent reports of increasing suicide rates among military personnel indicate a need for increased work in understanding processes relevant to suicide risk in the military. Anxiety, along with anxiety-related risk factors have been implicated in suicidality as well as posttraumatic stress disorder (PTSD). One such risk factor, anxiety sensitivity (AS), refers to fear of anxiety-related symptoms. Subfactors of AS, notably the physical and cognitive concerns factors, appear to be relevant to the construct of acquired capability for suicidal behavior, a risk factor for death by suicide postulated by the Interpersonal-Psychological Theory of Suicide (Joiner, 2005, Van Orden et al., 2010). Study 1 examined the interaction of AS-cognitive concerns and AS-physical concerns in an outpatient sample with PTSD symptomatology (N = 128). Analyses were consistent with our a priori model and indicated that the interaction of AS-cognitive concerns by AS-physical concerns predicted previous suicide attempt. Specifically, those with high AS-cognitive concerns and low AS-physical concerns were at increased risk for suicide attempt. Study 2 prospectively examined the associations between AS and suicidal ideation in a sample of military cadets undergoing basic training (N = 1081). A similar interaction emerged such that high AS-cognitive and low AS-physical scores at Time 1 significantly predicted suicidal ideation several months later, even after controlling for Time 1 suicidal ideation and psychopathology. These findings suggest that suicide potential may be related to interactions between cognitive risk factors for anxiety among individuals with PTSD symptomatology as well as individuals experiencing stressful life events.     

The "Golden Age" of prostate brachytherapy: a cautionary tale

PURPOSE: To investigate the earliest attempts to use man-made isotopes for prostate brachytherapy. METHODS AND MATERIALS: Two radiogold brachytherapy programs were analyzed, using literature review and interviews of participants. RESULTS: Although (198)Au has been discredited as a source for permanent prostate brachytherapy, the major flaw in the reviewed programs was the misapplication of the isotope. CONCLUSIONS: Safe and effective implant programs are grounded in the sound application of brachytherapy principles. New brachytherapy procedures should arise from the collaboration of radiation oncologists, surgeons, physicists, radiobiologists, and radiation safety specialists.     

Patterns of objectively measured physical activity in the United States

PURPOSE: We used latent class analysis (LCA) to assess patterns of physical activity among adults, using the 7 d of accelerometer data from the 2003-2004 NHANES. METHODS: For each participant, we determined the daily minutes of moderate-to-vigorous physical activity (MVPA), vigorous physical activity (VPA), and minutes of MVPA that occurred in bouts of 10 min. Participants were then categorized into patterns of activity, using LCA and adjusting for sociodemographic characteristics. RESULTS: For overall MVPA, five classes of physical activity were defined, including two least active classes, which averaged less than 25 min of MVPA per day and represented 78.7% of the total study population. The most active class averaged 134 min of MVPA per day and comprised 0.9% of the population. The results for bout minutes of MVPA were similar to the patterns produced for overall MVPA, with the exception of a "weekend warrior" class with moderate levels of physical activity Monday through Friday but with a much higher level of activity on the weekend, particularly on Sunday. This class represented 1.8% of the population. Only 1.4% of all days achieved 10 min or more of VPA, and in 91.1% of all days, participants accumulated less than 1 min of VPA. The LCA analysis of VPA did not produce stable results, because of the small number of participants registering any minutes of VPA. CONCLUSION: Our results indicate that a very large portion of the U.S. population may be classified into patterns of physical activity that represent low levels of MVPA throughout the week. The LCA analysis provided a novel approach for assessing patterns of objectively measured physical activity in epidemiologic studies.     

Magnetic resonance imaging of cystic adnexal lesions during pregnancy

Management of cystic adnexal lesions diagnosed during pregnancy is a challenging issue for obstetricians. The range of treatment options changes from immediate surgery to close follow-up. This pictorial essay illustrates the magnetic resonance imaging findings of various cystic adnexal lesions in pregnant patients. Magnetic resonance imaging may help in better characterization of some of the cystic adnexal lesions diagnosed during pregnancy without exposing the fetus to ionizing radiation.     

C-arm cone-beam CT: applications for spinal cement augmentation demonstrated by three cases

Spinal canal narrowing as a result of retropulsion of spinal structures before or during cement augmentation has been considered a contraindication to therapy. The authors describe three cases of compression fractures safely treated with cement augmentation with the novel application of C-arm cone-beam computed tomography (CT). All cases involved small amounts of posterior cement extrusion, after which osteotomy needles were left in place during C-arm cone-beam CT. Rapidly reformatted images were viewed with the use of bone windows, yielding three-dimensional visualization of pertinent anatomy to confirm endpoints of posterior extrusion and adequate bone filling.