Steep-dip seismic imaging of the shallow San Andreas fault near Parkfield.

Seismic reflection and refraction images illuminate the San Andreas Fault to a depth of 1 kilometer. The prestack depth-migrated reflection image contains near-vertical reflections aligned with the active fault trace. The fault is vertical in the upper 0.5 kilometer, then dips about 70 degrees to the southwest to at least 1 kilometer subsurface. This dip reconciles the difference between the computed locations of earthquakes and the surface fault trace. The seismic velocity cross section shows strong lateral variations. Relatively low velocity (10 to 30%), high electrical conductivity, and low density indicate a 1-kilometer-wide vertical wedge of porous sediment or fractured rock immediately southwest of the active fault trace.

Plastic elimination of functional glutamate release sites by depolarization.

To examine persisting effects of depolarizing rises in extracellular potassium concentration ([K+](o)) on synapses, we depolarized cells to simulate ischemia-like rises in [K+](o). Elevated [K+](o) for 1-16 hr severely depressed glutamate signaling, while mildly depressing GABA transmission. The glutamate-specific changes were plastic over several hours and involved a decrease in the size of the pool of releasable vesicles. Rather than a reduction of the number of vesicles per release site, the change involved functional elimination of release sites. This change was clearly dissociable from a second effect, depressed probability of transmitter release, which was common to both glutamate and GABA transmission. Thus, while other recent evidence links alteration of the releasable pool size with changes in p(r), our results suggest the two can be independently manipulated. Selective depression of glutamate release may provide an adaptive mechanism by which neurons limit excitotoxicity.

"A beacon of light". Spirituality in the heart transplant patient.

For the cardiac transplant recipients in this study, spirituality was like a beacon of light, providing illumination and sustaining hope while enduring illness. Spirituality was nurtured by Developing Faith and by the Presence of significant others, health care providers, and the Divine to sustain hope. Spirituality throughout the transplantation process was described by concepts of faith, presence, enduring illness, and sustaining hope. The four dynamic phases of Enduring Illness can assist health care providers in understanding what spirituality means to transplant patients. This conceptual model of spirituality demonstrates the important role that spirituality plays in recovery. Clinical application of this model will allow health care providers involved in the care of cardiac transplant patients to integrate spirituality into their patients' plan of care. With future research, this model can be easily modified and built upon to meet the needs of cardiac transplant patients in all phases of transplantation.

Intervention program components.

It is evident that those delivering health promotional services need training not only in the technical aspects of their profession, but in terms of enhancement of their organizational and management skills as well. Tasks associated with testing, data analysis, life style prescription, counselling, education, and safe and effective direction of program functions obviously require a multi-faceted staff. Screening and testing of fitness/wellness program clients is designed to identify those who can safely participate with likelihood of achieving their goals. Data from these procedures are used to formulate exercise and nutritional prescriptions and to serve as motivation. Counselling and educational efforts are aimed at servicing special needs of clients, providing motivation, increasing program visibility in the community and at enhancing program adherence. In view of the fact that fitness/wellness programs affect the health of participants and that certain aspects of these programs are hazardous, well worked-out schemes for providing emergency assistance and for otherwise protecting participants from harm must be in line and well-practiced. This need is enhanced by the fact that fitness/wellness programs and those who are associated with them are legally liable for physiological and mechanical accidents that can be traced to negligence.

Role of fluconazole in a case of rapid onset ritonavir and inhaled fluticasone-associated secondary adrenal insufficiency.

A 52-year-old man with well-controlled HIV infection taking ritonavir and increasing doses of inhaled fluticasone for chronic bronchitis developed thrush. Within days of discontinuing fluticasone and initiating fluconazole, he presented with fatigue, malaise, lower-extremity oedema and orthostasis. Testing confirmed exogenous Cushing's syndrome and secondary adrenal insufficiency. Although ritonavir-fluticasone interactions have been previously reported as a cause for adrenal insufficiency, we propose that fluconazole increased the rapidity of onset and severity of symptoms through synergistic inhibition of the adrenal axis.

Paclitaxel promotes a caspase 8-mediated apoptosis through death effector domain association with microtubules.

Microtubule-perturbing drugs have become front-line chemotherapeutics, inducing cell-cycle crisis as a major mechanism of action. However, these agents show pleiotropic effects on cells and can induce apoptosis through other means. Paclitaxel, a microtubule-stabilizing agent, induces a caspase-dependent apoptosis, although the precise mechanism(s) remain unclear. Here, we used genetic approaches to evaluate the role of caspase 8 in paclitaxel-mediated apoptosis. We observed that caspase 8-expressing cells are more sensitive to paclitaxel than caspase 8-deficient cells. Mechanistically, caspase 8 was found associated with microtubules, and this interaction increased after paclitaxel treatment. The prodomains death effector domains (DEDs) of caspase 8 were sufficient for interaction with microtubules, but the caspase 8 holoprotein was required for apoptosis. DED-only forms of caspase 8 were found in both primary and tumor cell lines, associating with perinuclear microtubules and the centrosome. Microtubule association, and paclitaxel sensitivity, depends on a critical lysine (K156) within a microtubule-binding motif (KLD) in DED-b of caspase 8. The results show an unexpected pathway of apoptosis mediated by caspase 8.

Improving clinical practice: should we give influenza vaccinations to heart transplant patients?

BACKGROUND: Current practice recommends that immunosuppressed patients (pts) receive yearly influenza (flu) vaccinations. However, disparity exists between current recommendations and clinical practice regarding the decision to administer flu vaccinations to heart transplant (Tx) pts. The purpose of this study was to examine the common clinical practices and outcome characteristics in Tx pts in a multi-institutional database. We assess the incidence of rejection, infection and flu in the months after administration of flu vaccinations. METHODS: Between 1990 and 2001, 5,581 pts underwent Tx at 28 institutions. Pts who were >1 year post-Tx as of January 1, 2002 (N = 3,601) constituted the study group. RESULTS: During the years 2002 and 2003, 89% of the institutions administered flu vaccines, with 7 institutions requiring pts to be >3 months (N = 1), 6 months (N = 1) and 12 months (N = 5) post-Tx. All 25 centers that vaccinated pts used trivalent inactivated vaccines during the months of October through January. Three centers did not vaccinate Tx pts due to a purported association with increased allograft rejection. There were no significant differences in the total number of rejection episodes (0.4% vs 0.3%, p = 0.7), rejection episodes by month (January: 0.4% vs 0%, p = 0.2; February: 0.5% vs 1.5%, p = 0.08; March: 0.5% vs 0%, p = 0.14), all infections (0.7% vs 0.6%, p = 0.6) and viral infections (0.1% vs 0%, p = 0.17) between centers that administered flu vaccines and those that did not, respectively. The incidence of flu was low in both groups. CONCLUSIONS: Flu vaccinations can be given safely to heart transplant pts without an increased incidence of rejection or infection. This information provides clinicians with data to improve clinical practice.

Neonatal assessment procedures: a historical review.

A historical review of neonatal assessment procedures is presented to demonstrate the trends in advancement of the field and attempts toward collaboration of medicine and psychology in contributions to the area. The literature suggests that the medically oriented neurological examinations have continued to be altered and improved. The growth of behaviorism within psychology and the view that behavior is closely related to underlying neurological mechanisms have contributed to the development of behaviorally oriented assessment procedures. These trends have combined successfully in the development of the Brazelton Neonatal Assessment Scale, which focuses on assessment of behavioral capabilities reflecting the quality of parent-infant relationships. The most recent contributions are directed toward development of specialized assessment techniques to fulfill specific research needs. Suggestions and cautions for use of available procedures are presented.

Postural stability measures: what to measure and for how long.

This paper assesses the repeatability of force plate postural stability measurements. The common parameters were investigated for five test durations, two vision conditions, and two stance conditions. All parameters were found to be reliable measures. Optimum test retest reliability was obtained at 20-s and 30-s trial periods. Centre of pressure measures increased with increased test duration while ground reaction forces and velocity decrease slightly. RELEVANCE:--The results indicate that measures of centre of pressure excursion and ground reaction forces can differentiate between various mechanical and sensory conditions and thus are clinically useful for detecting and quantifying both mechanical and sensorimotor postural deficiencies. It is also demonstrated that the test duration is important in the reliability and validity of stability measures.

Cardiorespiratory efficiency at submaximal work in young and middle-aged women.

Seventeen middle-aged women and 26 younger women were studied while walking at 3 mph and a 5% grade on a motorized treadmill. This was submaximal work for all subjects and is equivalent to the intensity of everyday activity. The middle-aged women had a significantly greater oxygen uptake, ventilatory equivalent, and heart rate, suggesting a relative cardiorespiratory inefficiency at this submaximal work intensity. This phenomenon is most likely a function of body size, however, since dividing the submaximal oxygen uptake by body weight rendered the mean difference between the two groups statistically insignificant. The age-associated reduction in cardiorespiratory efficiency at submaximal exercise is thus due primarily to weight gain rather than to actual systems degeneration. Maximal oxygen uptake, that associated with maximal physical effort, was significantly reduced in the older subjects, and this is probably due to a combination of previous life-style habits and aging.