Differential Effects of Left versus Right Monaural Biofeedback for Heart Rate Increase

Cerebral lateralization in the voluntary increase of heart rate was investigated in a biofeedback experiment involving 20 right-handed female subjects randomly assigned to one of two groups: right or left ear input of stimulus and biofeedback information. The stimulus was a 1000 Hz tone which signalled the start and duration of 30 20-sec training trials. Feedback was a click presented every time an interbeat interval was shorter than a criterion established through a shaping schedule. A monetary bonus provided additional reinforcement at the end of each trial. Subjects given right ear feedback increased their heart rate significantly more than subjects given left ear feedback. The largest difference between the group means (7 bpm) was recorded after the first 20 training trials. The results are discussed in terms of hemispheric perceptual and functional differences.     

The educational impact of ACGME limits on resident and fellow duty hours: a pre-post survey study.

PURPOSE: To assess the educational impact of Accreditation Council for Graduate Medical Education resident work-hour limits implemented in July 2003. METHOD: All trainees in all 76 accredited programs at two large teaching hospitals were surveyed between May and June 2003 (before work-hour reductions) and then between May and June 2004 (after work-hour reductions) about hours, education, and fatigue. Based on changes in weekly duty hours, 13 programs experiencing substantial reduction in hours were classified into a reduced-hours group. Differences in assessments of educational endpoints before and after policy implementation by trainees in the reduced-hours group were compared with those in other programs to control for potential temporal trends, using two-way ANOVA with interaction. RESULTS: The number of respondents was 1,770 (60% response rate). The reduced-hours group reported a significant decrease in time spent directly caring for patients (from 48.5 to 42.3 mean h/wk, P = 0.03), but the volume of important clinical experiences, including procedures, was preserved, as was the sense of clinical preparedness. On 22 questions related to educational quality and adequacy, only three differences in differences were significant, with the reduced-hours group reporting a relative increase in opportunities for research, decrease in quality of faculty teaching, and decrease in educational satisfaction. The percentage of trainees reporting frequent negative effects of fatigue dropped more in the reduced-hours programs than in the other programs (P < 0.05). CONCLUSION: This study shows that it may be possible to reduce residents' hours--and the perceived adverse impact of fatigue--while generally preserving the self-assessed quality, quantity, and outcomes of graduate medical education.     

Immunological variability associated with experimentally-induced positive and negative affective states.

Functional and phenotypic immunological parameters were examined immediately before, after, and 30 minutes after experimentally-induced short-term positive (happiness) and negative (anxiety, depression) affective states and a neutral state, in five healthy subjects. Results indicated that all affective states induced more immune fluctuations (regardless of the direction) than the neutral state. Furthermore, among the affective states, anxiety induced the most immunological variability and depression the least.     

Heart rate reactivity and heart period variability throughout the first year after heart transplantation

Heart rate reactivity to mental stress is substantially blunted early after heart transplantation, suggesting that the loss of neural modulation limits the cardiovascular response to mental stress. We tested whether reactivity to mental stress recovers during the first year after heart transplantation. Hemodynamic and respiratory responses to mental arithmetic challenge were studied in 20 heart transplant recipients 3, 6, and 12 months after surgery. A normal comparison group was studied at equivalent intervals. Heart rate reactivity to mental arithmetic was significantly reduced in the cardiac transplant group compared to the normal subjects. This effect persisted up to 1 year after transplantation. Heart period variability in the heart transplant recipients was minimal in all three-test sessions. The findings suggest that no functional reinnervation or other compensatory adaptation occurs up to 1 year after heart transplantation.     

Detecting antibodies with similar reactivity patterns in the HLDA8 blind panel of flow cytometry data

The blind panel collected for the 8th Human Leucocyte Differentiation Antigens Workshop (HLDA8; ) included 49 antibodies of known CD specificities and 76 antibodies of unknown specificity. We have identified groups of antibodies showing similar patterns of reactivity that need to be investigated by biochemical methods to evaluate whether the antibodies within these groups are reacting with the same molecule. Our approach to data analysis was based on the work of Salganik et al. (in press) [Salganik, M.P., Milford E.L., Hardie D.L., Shaw, S., Wand, M.P., in press. Classifying antibodies using flow cytometry data: class prediction and class discovery. Biometrical Journal].     

Cost effectiveness of individual vs. group cognitive behavior therapy for problems of depression and anxiety in an HMO population

Randomly assigned 44 outpatient Ss, enrollees of the George Washington University Health Plan, a Health Maintenance Organization (HMO), to one of three treatment modalities: (1) a cognitive behavior therapy group; (2) a traditional process-oriented interpersonal group; and (3) cognitive behavior therapy in an individual format. All Ss were referred by their physicians to the HMO Mental Health Practice for treatment for anxiety and/or depression. Beck's Depression Inventory, Speilberger's State-Trait Anxiety Inventory and Gay and Galassi's Adult Self-Expression Scale (an assertion measure) were administered pre- and post-treatment to all Ss. A subsample of these Ss also were rated pre- and post-treatment on the Hamilton Rating Scale for Depression by experienced clinicians blind to the treatment groups. All three experimental groups significantly improved on all dependent measures from pre- to post-treatment, and no differential treatment effects were found.     

Screening for cervical cancer in HIV-infected women receiving care in the United States

OBJECTIVE: We examined the sociodemographic, clinical and provider factors associated with screening for cervical cancer among HIV-infected women. METHODS: We studied a national sample representing 43,490 women receiving treatment of HIV infection who completed first follow-up surveys of the HIV Cost and Service Utilization Study (HCSUS). All women were asked, "In the past 12 months, have you had a Pap test?" Women reporting an abnormal Pap test result were asked whether they had been told antibiotics could cure abnormal cells, and whether they were scheduled for another Pap test or for a colposcopy within 3 months. RESULTS: Of the population represented, 81% had had a Pap test in the past 12 months. Women who reported having a gynecologist and primary care physician at the same clinical site were almost twice as likely (odds ratio, 1.9; 95% confidence interval, 1.3-3.0) as other women to report Pap testing. Among women who reported abnormal Pap test results and were not told antibiotics could cure abnormal cells, 95% were scheduled for a repeat Pap test or colposcopy, but 15% of the women had not received their repeat Pap test or colposcopy. CONCLUSION: Although Pap test rates and appropriate referral for abnormal findings were high among HIV-tested women, many women with initially abnormal Pap test results did not actually receive follow-up Pap testing or colposcopy. Providing gynecologic care at the same site as primary HIV care would likely improve delivery of needed gynecologic care for women.     

Malignant fibrous histiocytoma of bone: an ultrastructural study

An ultrastructural study of a case of malignant fibrous histiocytoma of bone in a 16-year-old skeletally mature female is presented. There were multiple metastatic bone lesions and a marked hypercalcemia. The cell population was similar to that found in soft tissue malignant fibrous histiocytoma lesions and comprised undifferentiated cells, fibroblastlike cells, histiocytes, and multinucleated giant cells. Occasional myofibroblasts and transitional cells with histiocytic and fibroblastic components were seen. The histiocytes were characterized by prominent Golgi bodies. Although there were many fibroblastlike cells, the rough endoplasmic reticulum was rarely as extensive or as well organized as in normal fibroblasts. The giant cells did not have the ultrastructural characteristics of osteoclasts, i.e., the clear zones and ruffled borders. Zonula adherens (belt desmosome) junctions were seen, but in general, intercellular junctions were poorly developed as to length and extent.     

Electrophysiological correlates of recovery of function

The present experiment was designed to determine the extent to which two different mechanisms were responsible for the recovery of function produced by grafts of fetal basal forebrain tissue into the hippocampus of rats given fimbria-fornix lesions. The place fields of single units in the hippocampus were recorded as rats moved about a radial arm maze. Two measures of the discriminative stimuli identifying the place fields were determined: place stability, maze stability. In control (CON) rats, place stability was high and maze stability was low, indicating that the relevant discriminative stimuli were extra-maze cues. In rats with fimbria-fornix (FF) lesions, place stability was low and maze stability was high, indicating that the relevant discriminative stimuli came from the maze itself. In rats given grafts of fetal basal forebrain tissue (GRAFT), place stability was increased and maze stability was reduced as compared to FF rats. These results indicate that the grafts produced recovery of function through restoration of normal hippocampal unit activity, rather than by reorganization of new neural networks.