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It is well known that extracorporeal surfaces have the ability to bind such drugs as fentanyl, nitroglycerine and propofol. Adsorption of the injectable anesthetic agent Diprivan® (propofol) onto uncoated and heparin-coated extracorporeal surfaces during cardiopulmonary bypass (CPB) has been previously investigated; however, propofol adsorption onto synthetic-coated extracorporeal surfaces has not been published previously. The focus of this investigation was on the interaction of propofol and the synthetic biomimetic coating from the Sorin Group called Mimesys® (phosphorylcholine (PC)). A randomized series of six in vitro experiments were done with propofol using both PC-coated circuits without arterial filters and those with arterial filters. The circuits were identical in all experiments and priming remained the same, with 750 mls of normal saline and 1250 mls of fresh bovine blood (hematocrit 41.0 ± 1.0%). After circulation and collection of baseline samples, the first (low) dose of 4 mg (4000 mcg) of Diprivan 1% was added to the perfusate, followed by the second (high) dose of 40 mg (40,000 mcg) and the final challenge (extreme dose) of 356 mg (356,000 mcg) of Diprivan.Drug assay was done by an independent laboratory, using the standardized method of High Performance Liquid Chromatography (HPLC). Measurements of total propofol were done at baseline, 20 minutes, 40 minutes and 60 minutes after each injection. Oxygenator performance was also measured prior to the addition of propofol and repeated after exposure to 4 mg, 40mg and 356 mg propofol for 60 min, 120 min and 180 minutes of circulation. Results indicate that phosphorylcholine coating does not prevent the adsorption of propofol during extracorporeal circulation and the oxygenator's gas exchange ability is not affected by prolonged exposure to an extreme dose of the medication during high flow extracorporeal circulation. [ABSTRACT FROM AUTHOR]

This article discusses the role of modal testing in the design and verification of spacecraft structures and describes equipment and techniques to perform modal survey tests. These tests become a more important part of the design and flight verification process as new generation spacecraft become larger. Described in this article are various upgrades that have been made to the facility's data acquisition system to meet the challenges of testing new generation spacecraft. Included is a real-time computer that is used to control exciters simultaneously and record motion and force data from up to 256 sensors.

Abstract Background Preliminary evidence suggests that the physical environment and transportation are associated with youth physical activity levels. Only a few studies have examined the association of physical environmental factors on walking and bicycling to school. Therefore, the purpose of this study was (1) to examine the test-retest reliability of a survey designed for youth to assess perceptions of physical environmental factors (e.g. safety, aesthetics, facilities near the home) and transportation, and (2) to describe the associations of these perceptions with both physical activity and active transport to school. Methods Test and retest surveys, administered a median of 12 days later, were conducted with 480 sixth- and eighth-grade girls in or near six U.S. communities. The instrument consisted of 24 questions on safety and aesthetics of the perceived environment and transportation and related facilities. Additionally, girls were asked if they were aware of 14 different recreational facilities offering structured and unstructured activities, and if so, whether they would visit these facilities and the ease with which they could access them. Test-retest reliability was determined using kappa coefficients, overall and separately by grade. Associations with physical activity and active transport to school were examined using mixed model logistic regression (n = 610), adjusting for grade, race/ethnicity, and site. Results Item-specific reliabilities for questions assessing perceived safety and aesthetics of the neighborhood ranged from 0.31 to 0.52. Reliabilities of items assessing awareness of and interest in going to the 14 recreational facilities ranged from 0.47 to 0.64. Reliabilities of items assessing transportation ranged from 0.34 to 0.58. Some items on girls' perceptions of perceived safety, aesthetics of the environment, facilities, and transportation were important correlates of physical activity and, in some cases, active transport to school. Conclusion This study provides some psychometric support for the use of the questionnaire on physical environmental factors and transportation for studying physical activity and active transport to school among adolescent girls. Further work can continue to improve reliability of these self-report items and examine their association of these factors with objectively measured physical activity.

Abstract Background Rising obesity and declining physical activity levels are of great concern because of the associated health risks. Many children are left unsupervised after the school day ends, but little is known about the association between unsupervised time and physical activity levels. This paper seeks to determine whether adolescent girls who are without adult supervision after school are more or less active than their peers who have a caregiver at home. Methods A random sample of girls from 36 middle schools at 6 field sites across the U.S. was selected during the fall of the 2002–2003 school year to participate in the baseline measurement activities of the Trial of Activity for Adolescent Girls (TAAG). Information was collected using six-day objectively measured physical activity, self-reported physical activity using a three-day recall, and socioeconomic and psychosocial measures. Complete information was available for 1422 out of a total of 1596 respondents. Categorical variables were analyzed using chi square and continuous variables were analyzed by t-tests. The four categories of time alone were compared using a mixed linear model controlling for clustering effects by study center. Results Girls who spent more time after school (≥2 hours per day, ≥2 days per week) without adult supervision were more active than those with adult supervision (p = 0.01). Girls alone for ≥2 hours after school, ≥2 days a week, on average accrue 7.55 minutes more moderate to vigorous physical activity (MVPA) per day than do girls who are supervised (95% confidence interval ([C.I]). These results adjusted for ethnicity, parent's education, participation in the free/reduced lunch program, neighborhood resources, or available transportation. Unsupervised girls (n = 279) did less homework (53.1% vs. 63.3%), spent less time riding in a car or bus (48.0% vs. 56.6%), talked on the phone more (35.5% vs. 21.1%), and watched more television (59.9% vs. 52.6%) than supervised girls (n = 569). However, unsupervised girls also were more likely to be dancing (14.0% vs. 9.3%) and listening to music (20.8% vs. 12.0%) (p < .05). Conclusion Girls in an unsupervised environment engaged in fewer structured activities and did not immediately do their homework, but they were more likely to be physically active than supervised girls. These results may have implications for parents, school, and community agencies as to how to structure activities in order to encourage teenage girls to be more physically active.

Background: Recent research demonstrates the importance of targeting the built environment to support individual physical activity, particularly for people experiencing health disparities. Master plans to promote biking and/or pedestrians (BPMPs) are a potential method for environmental change. This descriptive study aims to provide a snapshot of plan attributes and better understand demographic, social and transportation characteristics of communities with BPMPs., Methods: We collected a census sample of BPMPs from 4 states. Population and commuting data were obtained from national statistics., Results: 294 master plans were included, with most plans representing municipalities. 62% of plans targeted biking only, one-fifth targeted biking and walking, and 15% targeted walking only. The sampled locations have a similar demographic profile as the overall U.S. for median age and household income, people of color, high school education, and income inequality. The degree of racial diversity of sampled communities is slightly less than the U.S. average and the percentage of people who walk to work were slightly higher., Conclusions: Given that communities with master plans have a similar profile as the overall U.S., BPMPs could feasibly be spread to communities throughout the country. Further research is planned to describe BPMPs in detail toward informing future plan development.

Background: Trails provide opportunities for recreation, transportation and activity. The purpose of this article is to describe state legislation related to community trails, to analyze legislation content, and to evaluate legislation on inclusion of evidence-informed elements., Methods: State trail legislation from 2001 to 2008 was identified using online legislative databases. An analysis of evidence-informed elements included in the legislation was conducted. These elements included: funding, liability, accessibility, connectivity, and maintenance., Results: Of the total 991 trail bills, 516 (52.0%) were appropriations bills, of which 167 (32.2%) were enacted. We analyzed 475 (48%) nonappropriation trail bills of which 139 (29.3%) were enacted. The percentage of enactment of appropriations bills decreased over time while enactment of nonappropriations trail bills increased. Over half of the nonappropriations trail bills included at least 1 evidence-informed element, most commonly funding. Few bills contained liability, connectivity, accessibility, or maintenance., Conclusions: There is opportunity for providing evidence-informed information to policy-makers to potentially influence bill content. The number of bills with a funding element demonstrates that fiscal support for trails is an important policy lever that state legislatures may use to support trails. Lastly, trails should be considered in over-all state-level physical activity legislation to provide opportunities for communities to be active.

During a previously published study on gaseous microemboli (GMEs) and perfusionist interventions, it was noted that emboli could be detected after the arterial filter when blood/air challenges entered the membrane oxygenator's integral cardiotomy. The findings indicated that further study into the oxygenator's integral cardiotomy reservoir was warranted. This is the first know published report that connects the vent return to GME activity after the arterial filter. To study the air handling ability of the membranes integral cardiotomy, an in vitro study was conducted on five hard shell coated membrane oxygenators (Terumo Capiox SX25, X coated; Sorin Synthesis, phosphorylcholine coated; Gish Vision, GBS coated; Medtronic Affinity NT, trillium coated; Maquet Quadrox, bioline coated). The oxygenators were matched with their own manufacturer's coated arterial filters (Medtronic 351T Arterial Filter, Sorin Synthesis Integrated Arterial Filter, Terumo CXAF200X Arterial Filter, Gish GAF40GBS-2 Arterial Filter, and Maquet Quart HBF140 Arterial Filter). There were three arms to the study, and three separate oxygenator/filter combinations were used in each arm. The first arm consisted of a pump flow of 4.0 L/min with only the filter purge blood entering the integral cardiotomy. In the second arm, 500 mL/min of simulated vent blood was added to the filter purge blood entering the integral cardiotomy. During the final arm, 200 mL/min of air was added to the vent blood as it entered the integral cardiotomy, to more closely simulate vent return during cardiopulmonary bypass. All GME activity in the oxygenator/filter combinations was examined using the Hatteland CMD20 Microemboli Counter. Placement of the Hatteland probes was 4 in after the hard shell reservoir outlet (PRO) and 12 in after the arterial filter (PAF). When vent blood flow was turned on, there was a significant increase in the PRO microemboli activity detected in all reservoirs. In the PAF position, three of the oxygenator/filter combinations were able to remove 98-99% of the GME, one removed 84.3%, and another removed only 55.5% of the GMEs coming out of the oxygenator's reservoir. All oxygenators were found to have a dramatic increase in reservoir GME activity when the vent was turned on. Depending on the oxygenator/filter combination, vent return into the oxygenator's integral cardiotomy resulted in the presence of significant amounts of GMEs after the arterial filter.

Objective: This study examined the relationship between timing of sexual maturation and eating disorders symptoms in adolescent girls., Method: Data were collected over 10 years for a cohort of 1,213 Black girls and 1,166 White girls who were either 9 or 10 years old at study entry. Annually, girls' height and weight were measured and, biannually, girls completed self-report measures of eating disorders symptoms., Results: Early-onset menarche is a risk factor for the development of body image and dieting concerns, but the effect of timing is due to the impact of early and late maturation on body weight., Discussion: Findings underscore the importance of adiposity as a risk factor for poor mental health., (Copyright 2001 by John Wiley & Sons, Inc.)

Background: Antiepileptic drug (AED) therapy has been linked to bone disease that can be treated and prevented with calcium and vitamin D. However, because there have been no definitive studies on this subject, many physicians might not be aware of this association., Objective: To determine the approaches of neurologists to skeletal disorders in patients taking AEDs., Design: A self-administered mail survey., Participants: United States board-certified or board-eligible pediatric (n = 404) and adult (n = 624) neurologists., Main Outcome Measures: Practice patterns of neurologists regarding methods of screening for bone disorders and recommendations for treatment and prophylaxis., Results: Few pediatric (41%) and adult (28%) neurologists routinely evaluate AED-treated patients for bone and mineral disease. Of physicians who detect bone disease through diagnostic testing, 40% of pediatric and 37% of adult neurologists prescribe calcium or vitamin D, and about half (54% of pediatric and 57% of adult neurologists) refer patients to specialists. Few neurologists (9% of pediatric and 7% of adult neurologists) prescribe prophylactic calcium or vitamin D for patients taking AEDs., Conclusions: There is a lack of consensus among neurologists concerning the impact of AED therapy on bone. Because considerable evidence suggests that much of the bone pathology caused by AED therapy can be treated or prevented by administration of calcium and vitamin D, raising physician awareness of this problem could significantly improve the skeletal health of AED-treated individuals.

This article reviews short-term (6 months) and longer term (12-24 months) maintenance of cessation and relapse in adult smokers and the factors and treatments that affect these outcomes. MedLine and PsycLIT searches were done for research published in English between 1988 and 1998 meeting a defined set of criteria. Intensive intervention, telephone counseling, and use of pharmacotherapy were found to improve outcomes; however, compared with public health approaches, they reach relatively few smokers. Brief interventions during medical visits are cost-effective and could potentially reach most smokers but are not consistently delivered. Predictors of relapse include slips, younger age, nicotine dependence, low self-efficacy, weight concerns, and previous quit attempts. Potential areas for research, recommendations for longer follow-up assessments, and standard definitions for slip, relapse, and long-term maintenance are discussed.

Gaseous nitric oxide (NO) may act as a membrane passivator during cardiopulmonary bypass by inhibition of platelet and leukocyte adhesion, activation, and aggregation. However, NO and its by-product nitrogen dioxide (NO2) are potently reactive and may be capable of degradation of membrane oxygenator constituents in an oxygen-rich environment. To test these concepts, nine polypropylene hollow fiber membrane oxygenators received 224 +/- 10 ppm NO and 6.7 +/- 1.7 ppm NO2 in 73% oxygen (O2), and six oxygenators received 73% O2, while being perfused with heparinized thrombocytopenic bovine blood for 6 hours. Oxygenators were used for measurement of O2 and carbon dioxide (CO2) transfer rates, structural integrity by pulsing with 22 psi water at 0.5 Hz for 6 hours, and scanning electron microscopic (SEM) examination of structural integrity. Transfer rates between groups at 0, 1, 3, and 6 hours revealed no differences in O2 or CO2. No oxygenator failed hydraulic tests of structural integrity or exhibited "wet-out" during bypass. No evidence of material degradation was shown in the SEM appearance of oxygenators. There were no differences in hematologic values. These data support the safety of gaseous NO in polypropylene membrane oxygenators for limited-term cardiopulmonary bypass.

Background: Given the relatively low spontaneous quit rates and poor treatment outcomes among African American smokers, this study was designed to evaluate the effects of a multimodal culturally relevant intervention for smoking behavior change compared with a self-help strategy among urban African Americans in Baltimore churches., Method: This randomized controlled trial in urban African American churches used the stages of change model to compare the effectiveness of two interventions in moving smokers along a continuum toward smoking cessation. Twenty-two churches were randomly assigned to either an intensive culturally specific intervention or a minimal self-help intervention. Smokers were interviewed at baseline church health fairs and at a 1-year follow-up. Self-reported quitters at follow-up were evaluated using saliva cotinine and exhaled carbon monoxide levels (CO). Stages of change were measured by applying a standardized stages of change instrument to individual interview response sequences. Analysis compared the two intervention groups at 1-year follow-up with baseline stages. Outcomes included quit rates and positive progress along the stages of change., Results: Multiple logistic regression results, controlling for intrachurch correlation and demographic and baseline smoking characteristics, showed that the multimodal cultural intervention group was more likely to make positive progress along the stages of change continuum, compared with self-help intervention group (OR = 1.68; P = 0.04). Church denomination and intervention status interacted in the multivariate model; Baptists in the intensive intervention were three times (OR = 3.23; P = 0.010) more likely to make progress than all the other denomination groups., Conclusion: The multimodal culturally relevant intervention was more likely than a self-help intervention to positively influence smoking behavior. This is the first community-based intervention study to report progress along the stages of change as a process-oriented measure of success. It is notable that a spiritually based model focusing on environmental sanctions was more likely than a standard church disseminated self-help intervention to positively influence smoking behavior in an urban African American population.

The chronaxie (i.e., the duration for a stimulating current having twice the rheobasic, or minimum, value) was determined for ventricular myocardium in 12 pentobarbital-anesthetized dogs. Current was applied transthoracically via chest-surface electrodes located at the optimal axillary site for producing inspiration by stimulation of the phrenic nerve (electroventilation). In four dogs the chronaxie for motor-nerve was determined using electrodes at the same location. After using hand-held electrodes to identify the optimal stimulation site for electroventilation, 4.1 cm diameter electrodes were applied bilaterally to the optimal site on the thorax. In 12 dogs, the threshold current for producing ventricular ectopic beats was determined for single rectangular current pulses ranging from 0.1-10 ms in duration. From these data, strength-duration curves were determined and the average chronaxie for ventricular myocardium was found to be 1.82 ms. In four dogs the relationship between inspired volume and maximum stimulus intensity was determined using a 0.8 s burst of stimuli (60/s) with pulse durations ranging from 20-500 microseconds. From these data, strength-duration curves for current were constructed and the average chronaxie for motor-nerve was found to be 0.17 ms. The results of this study show that, because of the differing chronaxies, the current required to produce inspiration with short-duration stimuli is much less than that required to evoke an ectopic heart beat.

The threshold for ventricular fibrillation was determined in 12 pentobarbital anesthetized dogs using transthoracic electrodes located at the optimal axillary electroventilation sites. Electroventilation is the name used to designate inspiration produced by stimuli applied to body surface electrodes. The optimal stimulation site for electroventilation was first determined using hand-held electrodes. Then electrodes, 4.1 cm in diameter, were sutured bilaterally to the optimal anterior axillary stimulation site. The threshold current for producing ventricular fibrillation was determined using single pulses ranging from 0.1-10 msec in duration delivered during the vulnerable period of the cardiac cycle. Fibrillation was produced in all dogs with the 10- and 5-msec pulse durations, in 11 dogs with 0.3-msec, in 6 dogs with 0.2-msec, and in 1 dog with 0.1-msec pulse duration. In all dogs, the current required to produce ventricular fibrillation increased greatly as the pulse duration was decreased. The current required for fibrillation was much in excess of that required to produce one tidal volume. With the longer duration pulses, the ratio was about 80. With the 8 microseconds duration pulses used for electroventilation the estimated ratio is about 800.

In this preliminary study, artificial respiration was produced in four anesthetized horses using trains of stimuli applied to long needle electrodes inserted bilaterally at the base of the neck. The needles were insulated to within 1 cm of the tips. The frequency of the stimuli (0.1 msec) was 35/sec and the train duration (duration of inspiration) was 1 sec. Inspired volume increased with increasing stimulus intensity. In two animals, inspired volumes of 6 liters were achieved. In another animal 4.5 liters was achieved and in another, 2.5 liters. This lower value probably represented less-than-optimal electrode placement. Artificial percutaneous electrophrenic respiration was maintained for half an hour in every animal using a minute volume equivalent to that when breathing spontaneously.

Platelet damage in extracorporeal circuits occurs as the result of contact with foreign surfaces, shear stress, gas interface, and other nonphysiologic conditions. A scoring method developed to determine platelet activation was modified for evaluating platelet damage in extracorporeal circuits. This method assigns a numerical score to platelet damage, as assessed by direct visualization with phase microscopy. Various commercially available blood oxygenators were tested by using a modified AAMI/ASAIO in vitro blood trauma protocol. Direct gas contact oxygenators showed a marked decrease in total platelet count and significant platelet damage. Platelet depletion and platelet damage were lower in membrane oxygenators than in direct gas contact oxygenators. Differences in platelet damage were observed between membrane oxygenators. The observed differences between devices demonstrate the influence of materials and hemodynamic design on platelet depletion and damage. The method developed allows quantitative evaluation of platelet damage caused by extracorporeal devices and is a sensitive indicator of lethal and sublethal trauma.

Differences in the sources of information that physicians utilize in their practice have several implications for the quality of care delivered and the dissemination of medical information. In order to examine the extent of differences in information preferences in primary care settings, 98 general internal medicine physicians and 73 family physicians were asked to indicate which of six alternative information sources they relied on most when faced with difficult medical problems. The alternatives were: journals, textbooks, informal consultations with colleagues, consultations with community specialists, consultations with outside specialists, and transfer of the patient to another physician. The results indicated that primary care internists have a greater preference for consulting the medical literature, while family physicians more often rely on colleagues and specialists as sources of information. These differences suggest that the focus of information dissemination through journals or textbooks may be more effective for internists, while colleagues or "educationally influential" physicians in the community may be more effective vehicles for information dissemination to family physicians.