Simultaneous acquisition of functional magnetic resonance images and impedance cardiography

While simultaneous acquisition of electrocardiography (ECG) data during MRI is a widely used clinical technique, the effects of the MRI environment on impedance cardiography (ICG) data have not been characterized. We collected echo planar MRI scans while simultaneously recording ECG and thoracic impedance using carbon fiber electrodes and customized amplifiers. Here, we show that the key changes in impedance (dZ/dt) and features of the ECG waveforms are not obstructed during MRI. We present a method for ensemble averaging ICG/ECG signals collected during MRI and show that it performs comparably with signals collected outside the MRI environment. These results indicate that ICG can be used during MRI to measure stroke volume, cardiac output, preejection period, and left ventricular ejection time.     

Suicide in late life. Review and commentary

Increasing attention has been directed to recent increases in suicide rates for children, adolescents, and young adults. Nevertheless, persons 65 years and older continue to commit suicide at a higher rate than any other age group in the United States. In this paper various aspects of suicide are examined by analyzing recent trends among young and elderly populations, cohort suicide rates, and future projection of the number of suicides in late life. Data are derived from US death certificates. Consideration of the epidemiologic data and projections may be helpful both to those interested in public policy and to clinicians serving the elderly.     

Management of triplet pregnancies in the 1980s--are we doing better?

The incidence of triplet pregnancies has increased with the introduction of ovulation induction agents and is expected to further increase with the implementation of multiple embryo transfer in the in vitro fertilization programs. We review our experience with 29 triplet pregnancies in the last 10 years. Despite early sonographic diagnosis, close follow-up, increased use of tocolytics, and prophylactic cervical suture, we could not document prolongation of pregnancy, increased infants' weight, or a significantly decreased perinatal mortality, which still remains about 14%. Furthermore, the use of cesarean section as the delivery method of choice did not change the well-documented unfavorable relationship between birth order and fetal outcome. There is an urgent need for prospective assessment of the value of different treatment modalities, which nowadays becomes possible with the increasing incidence of triplet pregnancies. The prevention of triplet pregnancies or treatment by selective fetal reduction deserves a second thought.     

Health services access and use among older adults in North Carolina: urban vs rural residents.

OBJECTIVES. This study compared health service use and satisfaction with health care among older adults living in urban vs rural counties in North Carolina. METHODS. A stratified random sample of 4162 residents of one urban and four rural counties of North Carolina was surveyed to determine urban/rural variation in inpatient and outpatient health service use, continuity of care and satisfaction with care, and barriers (transportation, cost) to care. RESULTS. Inpatient and outpatient service use did not vary by residence in controlled analyses. Continuity of care was more frequent in rural counties. Transportation was not perceived as a barrier to health care more frequently in rural than in urban counties, but cost was a greater barrier to care among rural elderly people. CONCLUSIONS. In this sample, older persons living in rural counties within reasonable driving distance of urban counties with major medical centers used health services as frequently and were as satisfied with their health care as persons in urban counties. Cost of care, however, was a significant and persistent barrier among rural elderly people, despite Medicare coverage.     

Smoking history and epidermal growth factor receptor expression as predictors of survival benefit from erlotinib for patients with non-small-cell lung cancer in the National Cancer Institute of Canada Clinical Trials Group study BR.21

BACKGROUND: Erlotinib is an oral, reversible inhibitor of the HER1/epidermal growth factor receptor (EGFR) tyrosine kinase. A survival advantage for erlotinib compared with placebo was demonstrated in the National Cancer Institute of Canada Clinical Trials Group study BR.21, a randomized double-blind study of 731 patients with advanced-stage non-small-cell lung cancer. PATIENTS AND METHODS: In this retrospective, exploratory investigation, univariate and multivariate analyses of survival of the 311 patients with available EGFR status by immunohistochemistry and known smoking history were performed to determine which factor might be more important for predicting clinical outcome. RESULTS: A marginally significant interaction was observed between smoking history and treatment (P = 0.054). The hazard ratios (HRs) were 0.42 among never-smokers and 0.87 for smokers, indicating that erlotinib was beneficial in both subsets but more effective in patients who had never smoked. The HRs for patients with EGFR-positive and EGFR-negative tumors were 0.65 and 0.83, respectively; however, the interaction between EGFR status and treatment was not significant in univariate or multivariate analyses. Patients with EGFR-positive tumors who never smoked had the greatest survival benefit from erlotinib relative to placebo (HR, 0.28; P = 0.0007). CONCLUSION: These data suggest that never-smokers and patients with EGFR-positive tumors might experience an enhanced benefit from erlotinib compared with placebo but that smoking history might be more predictive of survival benefit than EGFR expression. Subset analyses of ever-smokers revealed significant survival advantages for men and patients with squamous cell histology. Male ever-smokers with squamous cell non-small-cell lung cancer derived a significant survival benefit from erlotinib (HR, 0.66; P = 0.015) despite a very low tumor response rate.     

Concurrent CIC mutations, IDH mutations, and 1p/19q loss distinguish oligodendrogliomas from other cancers

Oligodendroglioma is characterized by unique clinical, pathological, and genetic features. Recurrent losses of chromosomes 1p and 19q are strongly associated with this brain cancer but knowledge of the identity and function of the genes affected by these alterations is limited. We performed exome sequencing on a discovery set of 16 oligodendrogliomas with 1p/19q co-deletion to identify new molecular features at base-pair resolution. As anticipated, there was a high rate of IDH mutations: all cases had mutations in either IDH1 (14/16) or IDH2 (2/16). In addition, we discovered somatic mutations and insertions/deletions in the CIC gene on chromosome 19q13.2 in 13/16 tumours. These discovery set mutations were validated by deep sequencing of 13 additional tumours, which revealed seven others with CIC mutations, thus bringing the overall mutation rate in oligodendrogliomas in this study to 20/29 (69%). In contrast, deep sequencing of astrocytomas and oligoastrocytomas without 1p/19q loss revealed that CIC alterations were otherwise rare (1/60; 2%). Of the 21 non-synonymous somatic mutations in 20 CIC-mutant oligodendrogliomas, nine were in exon 5 within an annotated DNA-interacting domain and three were in exon 20 within an annotated protein-interacting domain. The remaining nine were found in other exons and frequently included truncations. CIC mutations were highly associated with oligodendroglioma histology, 1p/19q co-deletion, and IDH1/2 mutation (p < 0.001). Although we observed no differences in the clinical outcomes of CIC mutant versus wild-type tumours, in a background of 1p/19q co-deletion, hemizygous CIC mutations are likely important. We hypothesize that the mutant CIC on the single retained 19q allele is linked to the pathogenesis of oligodendrogliomas with IDH mutation. Our detailed study of genetic aberrations in oligodendroglioma suggests a functional interaction between CIC mutation, IDH1/2 mutation, and 1p/19q co-deletion.