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H atom loss following ultraviolet photoexcitation of 2-methyl, 3-furanthiol (2M,3FT) at many wavelengths in the range 269 nm > or = lambda(phot) > or = 210 nm and at 193 nm has been investigated by H (Rydberg) atom photofragment translational spectroscopy. The photodissociation dynamics of this SH decorated aromatic ring system are contrasted with that of thiophenol (Devine et al. J. Phys. Chem. A 2008, 112, 9563), the excited electronic states of which show a different energetic ordering. Ab initio theory and experiment find that the first excited state of 2M,3FT is formed by electron promotion from an orbital comprised of an admixture of the S lone pair and the furan pi system (n/pi) to a sigma* orbital centered on the S-H bond. Photoexcitation at long wavelengths results in population of the (1)(n/pi)sigma* excited state, prompt S-H bond fission, H atoms displaying a (nonlimiting) perpendicular recoil velocity distribution, and partner radicals formed in selected low vibrational levels of the ground state. This energy disposal can be rationalized by considering the forces acting as the excited molecules evolve on the (1)(n/pi)sigma* potential energy surface (PES). Energy conservation arguments, together with the product vibrational state analysis, yield a value of 31320 +/- 100 cm(-1) for the S-H bond strength in 2M,3FT. Excitation at shorter wavelengths (lambda(phot) < or = 230 nm) is deduced to populate one or more (diabatically bound) (1)(n/pi)pi* excited states which decay by coupling to the (1)(n/pi)sigma* PES and/or to high vibrational levels of the electronic ground state.

Objective: The purpose of this study was to examine the relationship between fasting serum leptin and adiponectin levels with bone mineral density (BMD) and body composition in pre-menopausal, middle-aged Hispanic and Caucasian women., Objective: Participants' (68 Hispanic and 36 Caucasian) BMD and bone mineral content were measured by dual-energy X-ray absorptiometry, and body density was measured by hydrodensitometry. Serum leptin was determined by enzyme immunoassay and adiponectin by ELISA., Results: Hispanic women had significantly higher leptin, BMD, and fat mass (FM), and lower adiponectin than Caucasian women. There was no significant correlation between leptin and BMD for Hispanic or Caucasian women; adiponectin was inversely correlated with BMD in Caucasian women only (p = 0.01). In both Hispanic and Caucasian women, lean body mass and adiponectin best explained the variance in BMD (r(2) = 0.25, p < 0.001)., Conclusion: These data demonstrate no significant relationship between leptin and BMD of pre-menopausal, middle-aged Hispanic and Caucasian women, and a significant inverse relationship between adiponectin and BMD in Caucasian women. The role of adipocytokines in the regulation of BMD remains inconclusive and may vary across ethnic groups.

Objective: The purpose was to evaluate the relationships between fasting serum leptin, resting metabolic rate (RMR), and body composition in premenopausal Hispanic and non-Hispanic White (White) women., Methods: Participants were 67 Hispanic and 43 White women who arrived at the laboratory in a fasted state for measurement of RMR by indirect calorimetry, bone mineral content measured by dual-energy X-ray absorptiometry, and body density measured by hydrodensitometry. Serum leptin levels were determined by EIA., Results: Multiple regression analysis revealed that body mass and lean body mass were the best predictors of RMR. Leptin was not a significant predictor of RMR., Conclusion: Further research needs to be done to examine the role of leptin on metabolism, especially in ethnic groups predisposed to development of obesity and related disorders.

Manual resistance training (MRT), an alternative to traditional resistance training, requires minimal equipment and may be effective when applied in school-based physical education (PE) classes. The purpose of this study was to document the physical changes in adolescents (n = 222) using MRT in school-based PE settings. Six fitness tests from the Fitnessgram assessment tool were selected to assess students' cardiovascular and muscular fitness, and skinfold tests were used to assess body composition. One control and 2 experimental groups were defined. The control group of students (n = 129) attended regular PE classes. One experimental group (n = 63) attended PE that was complemented by the MRT system. A second experimental group (n = 30) attended PE complemented by MRT and cardiovascular endurance training. With use of the selected Fitnessgram tests, post-test measurements were performed after 9 and 18 weeks of PE. At baseline, there were no significant differences among the 3 groups for most measures. Compared with baseline, the experimental groups improved significantly in all 6 fitness measures and showed more improvements than the control group in most fitness measures both at 9 and 18 weeks. None of the groups showed significant improvement in body composition. The results documented that an MRT-complemented PE program was effective in improving adolescents' muscular fitness. An 18-week combined MRT and cardiovascular endurance training program effectively improved cardiovascular and muscular fitness but was ineffective in improving adolescent body composition. An MRT-based exercise session requires minimal equipment and set-up and can be performed in a short period of time, and therefore it is suitable for application in regular PE settings.

The dissociation dynamics of gas phase phenol-d(5) molecules (C(6)D(5)OH) following excitation at numerous wavelengths in the range 275 > or = lambda(phot) > or = 193.3 nm have been investigated using the techniques of H (Rydberg) atom photofragment translational spectroscopy and resonance enhanced multiphoton ionization spectroscopy. The results are compared with those from recent studies of the fully hydrogenated and fully deuterated isotopologues (C(6)H(5)OH and C(6)D(5)OD), and various halo- and methyl-substituted phenols. Analysis of the vibrational energy disposal within the phenoxyl-d(5) dissociation products identifies three distinct O-H bond fission pathways, involving nonadiabatic coupling to dissociative states of (1)pisigma* character, following initial pi* <-- pi excitation. Dissociation at lambda(phot) > 248 nm involves internal conversion (IC) to high vibrational levels of the electronic ground ((1)pipi) state and subsequent coupling to the lowest (1)pisigma* potential energy surface (PES) via a conical intersection (CI) between the (1)pipi/(1)pisigma* PESs at extended O-H bond lengths (R(O-H)). Once lambda(phot) < or = 248 nm, dissociation proceeds directly, via a (1)pipi*/(1)pisigma* CI. Both pathways yield phenoxyl-d(5) products in selected vibrational levels of the ground (X(2)B(1)) electronic state. The detailed energy disposal within the phenoxyl-d(5)(X) products shows many parallels with that deduced from companion studies of other phenol isotopologues and various substituted phenols, but a notable isotope effect is identified, thus providing yet greater insights into the factors controlling the vibrational energy disposal in the phenoxyl products. A hitherto unobserved O-H bond fission channel yielding phenoxyl-d(5) fragments in the electronically excited B(2)A(2) state is identified at the shortest excitation wavelength (lambda(phot) = 193.3 nm) and rationalized in terms of nonadiabatic coupling to, and subsequent dissociation on, the second excited (1)pisigma* PES. Selective deuteration as in phenol-d(5) causes little reduction in the intensity of the "slower" H atom products that are observed from all phenol systems, suggesting that C-H/D bond fission makes at most a minor contribution to this feature.

Purpose: To investigate the effectiveness of a peer-mentored exercise program, this study compared the program perception, retention and participation rates, and physical improvements of older adults trained by peer mentors (PMs) with those of a group trained by student mentors (SMs)., Methods: After a 30-week peer-mentor preparation, 60 older adults (M +/- SD age: 68.7 +/- 6.1 yr) were recruited and randomly assigned to either the PM or the SM group. Both groups completed an identical 14-week fitness program. Pre- and posttraining assessments of fitness were completed, and the efficacy of the PMs and SMs was surveyed., Results: High retention was observed in both groups, but the SM group had higher participation. Both groups improved their fitness significantly, with no significant posttest differences between the groups in most fitness measures or in program perception rates., Discussion: Findings suggest effectiveness of the peer-mentor model in an older adult exercise program.

The purpose of this study was to investigate the effects of a manual resistance training (MRT) program on muscular strength and endurance and to compare these effects with those of an identically structured weight resistance training (WRT) program. To do this, 84 healthy college students were randomly assigned to either an MRT (n = 53, mean +/- SD: age 25.6 +/- 6.0 years, height 170.1 +/- 8.1 cm, body mass 73.9 +/- 16.0 kg, and body fat 24.6 +/- 8.7%) or WRT (n = 31, mean +/- SD: age 25.5 +/- 5.2 years; height 169.6 +/- 10.1 cm, body mass 75.0 +/- 17.4 kg, and body fat 24.7 +/- 8.5%) group and engaged in a 14-week training program. Each participant's performance was assessed before and immediately after the 14-week training period. Muscular strength was assessed by the one-repetition maximum (1RM) bench press test and the 1RM squat test. Muscular endurance was recorded as the maximum number of repetitions performed with 70% of pretraining 1RM for the bench press and squat exercises. There were no significant differences between the MRT and WRT groups at baseline for muscular strength (p > 0.36) or muscular endurance (p > 0.46). Compared with baseline values, the 14-week training programs produced significant (p < 0.001) improvements in muscular strength and muscular endurance of the MRT and WRT groups. However, no significant difference was observed between the MRT and WRT groups for muscular strength (p > 0.22) or for muscular endurance (p > 0.09) after training. The improvements in muscular strength and muscular endurance after a 14-week MRT program in the present study were similar to those produced by a WRT program, and well-designed MRT exercises seem to be effective for improving muscular fitness.

The photodissociation of jet-cooled 4-, 3- and 2-methylphenol molecules has been investigated using the experimental techniques of resonance enhanced multiphoton ionisation and H (Rydberg) atom photofragment translational spectroscopy. O-H bond fission is found to occur, via a repulsive (1)pisigma state, in a manner analogous to that occurring in phenol and 4-fluorophenol. Excitation to the (1)pipi manifold results in H-atom loss either directly (via a (1)pipi/(1)pisigma conical intersection) or indirectly, following internal conversion to the ground state and subsequent coupling to the (1)pisigma state via a second conical intersection at extended O-H bond lengths. The resulting methylphenoxyl radicals are created with specific vibrational excitation, reflecting the nuclear distortions required to access the (1)pisigma potential energy surface and the geometry changes induced by subsequent H atom loss. The position of the methyl group on the benzene ring is observed to influence the product vibrational energy disposal-not least through its influence on the mode(s) that are activated as a result of coupling to the repulsive (1)pisigma state. O-H bond strengths are reported for 4-, 3- and 2-methylphenol. These are in good agreement with values derived from recent combustion calorimetry studies and serve to highlight the relative destabilisation of the radical caused by methyl substitution at the 3-position.

High-resolution time-of-flight measurements of H atom products from photolysis of phenol, 4-methylphenol, 4-fluorophenol, and thiophenol, at many UV wavelengths (lambda(phot)), have allowed systematic study of the influence of ring substituents and the heteroatom on the fragmentation dynamics. All dissociate by X-H (X = O, S) bond fission after excitation at their respective S(1)((1)pipi*)-S(0) origins and at all shorter wavelengths. The achieved kinetic energy resolution reveals population of selected vibrational levels of the various phenoxyl and thiophenoxyl coproducts, providing uniquely detailed insights into the fragmentation dynamics. Dissociation in all cases is deduced to involve nuclear motion on the (1)pisigma* potential energy surface (PES). The route to accessing this PES, and the subsequent dynamics, is seen to be very sensitive to lambda(phot) and substitution of the heteroatom. In the case of the phenols, dissociation after excitation at long lambda(phot) is rationalized in terms of radiationless transfer from S(1) to S(0) levels carrying sufficient O-H stretch vibrational energy to allow coupling via the conical intersection between the S(0) and (1)pisigma* PESs at longer O-H bond lengths. In contrast, H + C(6)H(5)O(X(2)B(1)) products formed after excitation at short lambda(phot) exhibit anisotropic recoil-velocity distributions, consistent with prompt dissociation induced by coupling between the photoprepared (1)pipi* excited state and the (1)pisigma* PES. The fragmentation dynamics of thiophenol at all lambda(phot) matches the latter behavior more closely, reflecting the different relative dispositions of the (1)pipi* and (1)pisigma* PESs. Additional insights are provided by the observed branching into the ground (X(2)B(1)) and first excited ((2)B(2)) states of the resulting C(6)H(5)S radicals.

Molecular oxygen is toxic for anaerobic organisms but it is also obvious that oxygen is poisonous to aerobic organisms as well, since oxygen plays an essential role for inducing molecular damage. Molecular oxygen is a triplet radical in its ground-stage (.O-O.) and has two unpaired electrons that can undergoes consecutive reductions of one electron and generates other more reactive forms of oxygen known as free radicals and reactive oxygen species. These reactants (including superoxide radicals, hydroxyl radicals) possess variable degrees of toxicity. Nitric oxide (NO*) contains one unpaired electron and is, therefore, a radical. NO* is generated in biological tissues by specific nitric oxide synthases and acts as an important biological signal. Excessive nitric oxide production, under pathological conditions, leads to detrimental effects of this molecule on tissues, which can be attributed to its diffusion-limited reaction with superoxide to form the powerful and toxic oxidant, peroxynitrite.Reactive oxygen and nitrogen species are molecular "renegades"; these highly unstable products tend to react rapidly with adjacent molecules, donating, abstracting, or even sharing their outer orbital electron(s). This reaction not only changes the target molecule, but often passes the unpaired electron along to the target, generating a second free radical, which can then go on to react with a new target amplifying their effects.This review describes the mechanisms of oxidative damage and its relationship with the most highly studied neurodegenerative diseases and the roles of melatonin as free radical scavenger and neurocytoskeletal protector.

The photolysis of pyrrole has been studied in a molecular beam at wavelengths of 250, 240, and 193.3 nm, using two different carrier gases, He and Xe. A broad bimodal distribution of H-atom fragment velocities has been observed at all wavelengths. Near threshold at both 240 and 250 nm, sharp features have been observed in the fast part of the H-atom distribution. Under appropriate molecular beam conditions, the entire H-atom loss signal from the photolysis of pyrrole at both 240 and 250 nm (including the sharp features) disappear when using Xe as opposed to He as the carrier gas. We attribute this phenomenon to cluster formation between Xe and pyrrole, and this assumption is supported by the observation of resonance enhanced multiphoton ionization spectra for the (Xe...pyrrole) cluster followed by photofragmentation of the nascent cation cluster. Ab initio calculations are presented for the ground states of the neutral and cationic (Xe...pyrrole) clusters as a means of understanding their structural and energetic properties.

The importance of understanding the role of atmospheric conditions in pollen dispersal has grown in recent years with increased field-testing of genetically modified (GM) crop plants. An atmospheric model was used to characterize wind trajectories at 10 m and 100 m above GM pollen source fields located within a 4452-ha "control" area north of Madras, Oregon, USA, designated by the Oregon Department of Agriculture (ODA). The area was used in 2003 for the growth of GM creeping bentgrass (Agrostis stolonifera) engineered to be resistant to glyphosate herbicide. The presence of the GM gene (CP4 EPSPS) provided a distinct selectable marker for pollen-mediated gene flow to sentinel and resident Agrostis spp. plants. Linkage of GM gene presence with wind flow characteristics over the "control" area became essential to understand the timing and processes leading to long-distance transport of this pollen. Wind trajectories showed a general pattern of northwest to southeast air movement. Trajectory travel distances calculated hourly from 06:00 hours to 15:00 hours during the 2003 pollination period (15 June-15 July) showed movement up to 15 km from the "control" area's center by the first hour. Maximum travel distances increased to 40 and 55 km after two and three hours from release, respectively. Calculated wind trajectory positions corresponded with observed long-distance pollen-mediated gene flow in the seedlings of sentinel and resident plants. The highest correlations were found during the late morning hours. Back-calculated wind trajectories from sentinel and resident locations with GM-gene-positive progeny suggested that most successful fertilizations occurred in the direction of prevailing winds during late June 2003. The occurrence of positive progeny from sentinel plants, upwind of the "control" area during this period, indicated the additional influence of local topography on pollen dispersal.

Concerns about genetically modified (GM) crops include transgene flow to compatible wild species and unintended ecological consequences of potential transgene introgression. However, there has been little empirical documentation of establishment and distribution of transgenic plants in wild populations. We present herein the first evidence for escape of transgenes into wild plant populations within the USA; glyphosate-resistant creeping bentgrass (Agrostis stolonifera L.) plants expressing CP4 EPSPS transgenes were found outside of cultivation area in central Oregon. Resident populations of three compatible Agrostis species were sampled in nonagronomic habitats outside the Oregon Department of Agriculture control area designated for test production of glyphosate-resistant creeping bentgrass. CP4 EPSPS protein and the corresponding transgene were found in nine A. stolonifera plants screened from 20,400 samples (0.04 +/- 0.01% SE). CP4 EPSPS-positive plants were located predominantly in mesic habitats downwind and up to 3.8 km beyond the control area perimeter; two plants were found within the USDA Crooked River National Grassland. Spatial distribution and parentage of transgenic plants (as confirmed by analyses of nuclear ITS and chloroplast matK gene trees) suggest that establishment resulted from both pollen-mediated intraspecific hybridizations and from crop seed dispersal. These results demonstrate that transgene flow from short-term production can result in establishment of transgenic plants at multi-kilometre distances from GM source fields or plants. Selective pressure from direct application or drift of glyphosate herbicide could enhance introgression of CP4 EPSPS transgenes and additional establishment. Obligatory outcrossing and vegetative spread could further contribute to persistence of CP4 EPSPS transgenes in wild Agrostis populations, both in the presence or absence of herbicide selection.

Background: There have been few reports of the world views, values and priorities of families of children with autism or Down syndrome, despite the fact that family belief systems are considered to be among the most important factors affecting the adaptation and resilience of families., Methods: Transcripts from three focus groups involving 19 key informants (15 parents of children with autism or Down syndrome, and 4 service providers) were analysed using qualitative methods., Results: The themes indicated that raising a child with a disability can be a life-changing experience that spurs families to examine their belief systems. Parents can come to gain a sense of coherence and control through changes in their world views, values and priorities that involve different ways of thinking about their child, their parenting role, and the role of the family. Although parents may grapple with lost dreams, over time positive adaptations can occur in the form of changed world views concerning life and disability, and an appreciation of the positive contributions made by children to family members and society as a whole. Parents' experiences indicate the importance of hope and of seeing possibilities that lie ahead., Conclusions: The information from this study may be used to provide families with an advance understanding of the changes in beliefs that they might undergo, and assists service providers in providing individualized and family-centred services and supports to families.

The purpose of the study was to evaluate the validity of an air-displacement plethysmography system (AP) within the general population, while wearing (1) a racing-type swimsuit (AP(SS)) and (2) participant's personal undergarments (AP(UG)), against hydrodensitometry (HW). Fifty women and 50 men were measured for body volume, density, and fat percentage by HW and compared with AP(SS) and AP(UG). For women, AP(UG) and AP(SS) were similar, although significant differences (p < 0.001) were observed between AP(UG) and HW and between AP(SS) and HW. For men, there was no significant difference between AP(UG) and HW; however, significant differences (P < or = 0.01) were found between AP(UG) and AP(SS) and between AP(SS) and HW. The small discrepancy in measured values between AP and HW are within the measurement error for the instrumentation and these data support the use of AP for determination of body composition in adults across a wide range of body size (body mass index [BMI] 17.7-35.2 kg.m(-2)) and age (18-57 y). Participants' personal undergarments provide a practical alternative to a spandex swimsuit when measuring body composition by AP in women but not in men.

A growing body of research supports cooperative learning as an effective teaching strategy. A specific cooperative learning strategy, Team-based Learning, was applied to a convenience sample of four undergraduate sophomore-level motor behavior courses over four semesters from Fall 2002 to Spring 2004 to examine whether this strategy would affect students' learning styles. The data from the Grasha-Reichmann Student Learning Style Scales indicated that this teaching strategy was associated with a significant decrease in the negative Avoidant and Dependent learning styles and an improvement in the positive Participant learning style.

A motivational, developmental meta-model of the meaning of everyday life experiences is presented. The model proposes that there are 3 fundamental ways in which people establish meaning across the life span: the paths of belonging (relationships), doing (meaningful engagement in activities), and understanding oneself and the world. The principles of the model include intertwined, fundamental meanings of human experience; the indeterminacy of cause and effect; individual differences in preferences for ways of attaining meaning; the importance of commitments in life; and life-long adaptation and changes in meaning. The model provides an organizing framework that clarifies the assumptions of various disciplinary frames of reference with respect to establishing meaning in everyday life. Implications of the model are discussed for the rehabilitation sciences and rehabilitation service delivery.

Background: In the United States, non-Hispanic blacks have higher rates of hypertension than other ethnic groups. In addition, they have higher rates of physical inactivity, a behavior linked to high blood pressure. We examined associations between ethnicity, leisure-time physical activity (LTPA), and hypertension prevalence in a representative sample of U.S. adults., Methods: Using data on 16,246 adults in the third National Health and Nutrition Examination Survey, hypertension prevalence was determined for non-Hispanic white, non-Hispanic black, and Mexican Americans at various levels of LTPA (none, 0.1-4.9 bouts/week at any intensity, 5+ bouts/week of moderate-to-vigorous activity). Logistic regression was used to examine relationships between hypertension prevalence, race, LTPA, and other variables., Results: Hypertension prevalence was significantly less in the most active group, compared with their sedentary peers (odds ratio = 0.73, CI 0.59 to 0.90). Blacks had an odds ratio for hypertension of 1.77 (CI 1.49 to 2.10) compared with non-Hispanic whites, after adjusting for gender, age, income, LTPA, smoking, BMI, salt intake, rural/urban dwelling, and alcohol intake. Mexican Americans had an adjusted odds ratio of 0.75 (CI 0.62 to 0.89), relative to non-Hispanic whites., Conclusion: Ethnicity and LTPA are both associated with hypertension prevalence after controlling for each other, as well as other confounders. Thus, race and physical activity are important independent contributors to hypertension prevalence., (Copyright 2002 American Health Foundation and Elsevier Science (USA).)

The accuracy of a computerized metabolic system, using inspiratory and expiratory methods of measuring ventilation, was assessed in eight male subjects. Gas exchange was measured at rest and during five stages on a cycle ergometer. Pneumotachometers were placed on the inspired and expired side to measure inspired (VI) and expired ventilation (VE). The devices were connected to two systems sampling expired O(2) and CO(2) from a single mixing chamber. Simultaneously, the criterion (Douglas bag, or DB) method assessed VE and fractions of O(2) and CO(2) in expired gas (FE(O(2)) and FE(CO(2))) for subsequent calculation of O(2) uptake (VO(2)), CO(2) production (VCO(2)), and respiratory exchange ratio. Both systems accurately measured metabolic variables over a wide range of intensities. Though differences were found between the DB and computerized systems for FE(O(2)) (both inspired and expired systems), FE(CO(2)) (expired system only), and VO(2) (inspired system only), the differences were extremely small (FE(O(2)) = 0.0004, FE(CO(2)) = -0.0003, VO(2) = -0.018 l/min). Thus a computerized system, using inspiratory or expiratory configurations, permits extremely precise measurements to be made in a less time-consuming manner than the DB technique.

The purpose of this investigation was to assess the accuracy of the COSMED K4 b2 portable metabolic measurement system against the criterion Douglas bag (DB) method. During cycle ergometry on consecutive days, oxygen consumption (VO2), carbon dioxide production (VCO2), minute ventilation (VE), and respiratory exchange ratio (R) were measured at rest and during power outputs of 50, 100, 150, 200, and 250W. No significant differences (P > 0.05) were observed in VO2 between the K4 b2 and DB at rest and at 250W. Though the K4 b2 values were significantly higher (P<0.05) than DB values at 50, 100, 150, and 200 W, the magnitude of these differences was small (0.088, 0.092, 0.096, and 0.088 L x min(-1), respectively). VCO2 and VE values from the K4 b2 were significantly lower than the DB at 200 and 250 W, while no significant differences were observed from rest through 150W. The slight overestimation of VO2 (50-200 W) combined with the underestimation of VCO2 (200 and 250W) by the K4 b2 resulted in significantly lower R values at every stage. These findings suggest the COSMED K4 b2 portable metabolic measurement system is acceptable for measuring oxygen uptake over a fairly wide range of exercise intensities.

In this article, the psychosocial themes emerging from an exploratory qualitative study are reported. Using a constant comparative method, the authors describe how older adolescents with cerebral palsy defined success in life and the factors they viewed as helping or hindering their success. Participants were 10 adolescents with cerebral palsy between 18 and 20 years of age who took part in a semistructured interview exploring their perceptions of success. For these adolescents, success meant being happy in life. Three key psychosocial factors were related to success in life: being believed in, believing in yourself, and being accepted by others (belonging). The findings are useful in guiding the design of services to meet the life needs of individuals with disabilities.

Unlabelled: To further develop our understanding of the relationship between habitual physical activity and health, research studies require a method of assessment that is objective, accurate, and noninvasive. Heart rate (HR) monitoring represents a promising tool for measurement because it is a physiological parameter that correlates well with energy expenditure (EE). However, one of the limitations of HR monitoring is that training state and individual HR characteristics can affect the HR-VO2 relationship., Purpose: The primary purpose of this study was to examine the relationship between HR (beats x min(-1)) and VO2 (mL x kg(-1 x -1) min(-1)) during field- and laboratory-based moderate-intensity activities. In addition, we examined the validity of estimating EE from HR after adjusting for age and fitness. This was done by expressing the data as a percent of heart rate reserve (%HRR) and percent of VO2 reserve (%VO2R)., Methods: Sixty-one adults (18-74 yr) performed physical tasks in both a laboratory and field setting. HR and VO2 were measured continuously during the 15-min tasks. Mean values over min 5-15 were used to perform linear regression analysis on HR versus VO2. HR data were then used to predict EE (METs), using age-predicted HRmax and estimated VO2max., Results: The correlation between HR and VO2 was r = 0.68, with HR accounting for 47% of the variability in VO2. After adjusting for age and fitness level, HR was an accurate predictor of EE (r = 0.87, SEE = 0.76 METs)., Conclusion: This method of analyzing HR data could allow researchers to more accurately quantify physical activity in free-living individuals.

Purpose: This study tested the validity of four motion sensors for measuring energy expenditure (EE) during moderate intensity physical activities in field and laboratory settings. We also evaluated the accuracy of the EE values for selected moderate activities listed in the 1993 Compendium of Physical Activities., Methods: A total of 81 participants (age 19-74 yr) completed selected tasks from six general categories: yardwork, housework, occupation, family care, conditioning, and recreation. Twelve individuals performed each of the 28 activities examined. During each activity, EE was measured using a portable metabolic measurement system. Participants also wore three accelerometers (Computer Science and Applications [CSA], Inc. model 7164; Caltrac; and Kenz Select 2) and the Yamax SW-701 electronic pedometer. For the CSA device, three previously developed regression equations were used to convert accelerometer scores to EE., Results: The mean error scores (indirect calorimetry minus device) across all activities were: CSA1, 0.97 MET; CSA2, 0.47 MET, CSA3, 0.05 MET; Caltrac, 0.83 MET; Kenz, 0.96 MET; and Yamax, 1.12 MET. The correlation coefficients between indirect calorimetry and motion sensors ranged from r = 0.33 to r = 0.62. The energy cost for power mowing and sweeping/mopping was higher than that listed in the 1993 Compendium (P < 0.05), and the cost for several household and recreational activities was lower (P < 0.05)., Conclusion: Motion sensors tended to overpredict EE during walking. However, they underpredicted the energy cost of many other activities because of an inability to detect arm movements and external work. These findings illustrate some of the limitations of using motion sensors to predict EE in field settings.

Purpose: This study was designed to establish prediction models that relate hip and wrist accelerometer data to energy expenditure (EE) in field and laboratory settings. We also sought to determine whether the addition of a wrist accelerometer would significantly improve the prediction of EE (METs), compared with a model that used a hip accelerometer alone., Methods: Seventy participants completed one to six activities within the categories of yardwork, housework, family care, occupation, recreation, and conditioning, for a total of 5 to 12 participants tested per activity. EE was measured using the Cosmed K4b2 portable metabolic system. Simultaneously, two Computer Science and Applications, Inc. (CSA) accelerometers (model 7164), one worn on the wrist and one worn on the hip, recorded body movement. Correlations between EE measured by the Cosmed and the counts recorded by the CSA accelerometers were calculated, and regression equations were developed to predict EE from the CSA data., Results: The wrist, hip, and combined hip and wrist regression equations accounted for 3.3%, 31.7%, and 34.3% of the variation in EE, respectively. The addition of the wrist accelerometer data to the hip accelerometer data to form a bivariate regression equation, although statistically significant (P = 0.002), resulted in only a minor improvement in prediction of EE. Cut points for 3 METs (574 hip counts), 6 METs (4945 hip counts), and 9 METs (9317 hip counts) were also established., Conclusion: The small amount of additional accuracy gained from the wrist accelerometer is offset by the extra time required to analyze the data and the cost of the accelerometer.

We assessed a treatment plan of local therapy (resection and placement of permanent low dose-rate I-125 seeds) without whole brain irradiation in 15 patients with solitary brain metastasis (SBM) from primary non-small cell lung cancer between January, 1991 and May, 1996. Thirteen lesions were confirmed as solitary by MRI scan, and 2 patients had CT scan only. With median follow up of 14 months, 3 patients remain alive at 6, 33, and 62 months post-resection. Median survival is 14 months for all patients and 26 months for patients with SBM as the only site of disease. Five tumors failed in the brain: 2 solitary recurrences adjacent to the site of SBM, 2 multiple metastases outside the primary site, and 1 multiple recurrence including the primary site. No failures were seen with SBM <2.5 cm. Only 2 of 13 patients with SBM confirmed with MRI experienced relapses elsewhere in the brain. Recurrence rates both adjacent and outside the area of the initial brain lesion are similar to studies employing resection plus whole brain irradiation (WBI), and the patient is spared the acute and potential late toxicity of WBI. This approach may be considered for selected patients with solitary brain metastases (SBMs), although further experience with larger patient numbers is needed.

The purpose of this study was to test the validity of the Aerosport KB1-C portable metabolic measurement system against the criterion Douglas bag method. During cycle ergometry, simultaneous measurements of minute ventilation (VE), oxygen consumption (VO2), and carbon dioxide production (VCO2) were made at rest and at power outputs of 50, 100, 150, 200, and 250 W. No significant differences (P > 0.05) were observed for VE, VO2, and VCO2 between the KB1-C and Douglas bag at 100, 150, and 250 W, while the KB1-C was significantly different (P < 0.05) from Douglas bag values at rest, 50, and 200 W. R values were found to be significantly different (P < 0.05) at 100, 150, and 200 W, while no significant differences were observed at rest, 50, and 250 W. The fractional concentrations of oxygen (FEO2) and carbon dioxide (FECO2) were not significantly different at 50, 100, 200, and 250 W while values at rest and 150 W were significantly different (P < 0.05). These findings show that the Aerosport KB1-C portable metabolic system is acceptable for measuring oxygen uptake in the range of 1.5 and 3.5 L x min(-1), using the medium flow pneumotach setting. At lower intensities, the low-flow pneumotach setting provides acceptable results.

We determined optimum conditions for delivering DNA to transformed human bronchial epithelial cells expressing wild-type (BEAS) or abnormal (2CF) cystic fibrosis transmembrane conductance regulator (CFTR) using cationic liposomes (Lipofectin, [N-(N,N-dimethylaminoethane)carbamyl] cholesterol[DC-Chol]/dioleoylphosphatidylethanolamine[DOPE], or LipofectAMINE) and reporter genes which measured overall transgene expression (luciferase) or the fraction of cells transfected (heat-stable alkaline phosphatase). All liposomes showed dose-related toxicity. Optimal liposome and lipid: DNA ratios were different for BEAS than for 2CF cells. For all 3 liposome preparations, small particle size and net cationic charge related to transfection efficiency. Both LipofectAMINE and DC-Chol/DOPE transfected a maximum of 3% of BEAS cells, but luciferase expression could be increased without increasing the fraction of cells transfected. LipofectAMINE transfected a maximum of 6% of 2CF cells, and luciferase expression could be increased with no further increase in fraction of transfected cells. DC-Chol/DOPE transfected over 12% of 2CF cells with relatively small increases in luciferase expression. We conclude that an optimal cationic liposome and lipid: DNA ratio for transfecting bronchial epithelial cells depends on: (1) small particle size and net cationic charge, (2) whether the cells have the cystic fibrosis defect, and (3) whether the desired outcome is transfection of the maximum fraction of the cells or maximum total expression of the transgene.

This article describes the use of a newly-developed measure of parents' perceptions of health care providers' behaviours (Measure of Processes of Care-MPOC) to evaluate the family centredness of children's rehabilitation services. The measure was developed with the participation of more than 1600 parents of children with chronic neurodevelopmental conditions throughout Ontario. It assesses five domains: enabling and partnership; providing general information; providing specific information about the child; coordinated and comprehensive care; and respectful and supportive care. By comparing the perceptions of parents receiving services from three different types of organizations or programmes, we demonstrated that the MPOC can pick up differences between parents in their experiences of caregiving. We also demonstrated that the MPOC is able to detect differences in how parents view the family-centredness of services provided by individual centres. The data indicate that the MPOC has appreciable utility in providing programmes and services with a description of their current level of family-centred service as perceived by parents. The strengths, limitations and potential uses of the measure in other contexts are discussed.

We previously isolated a cDNA clone, pTIP13, whose homologous mRNA rapidly declined in abundance in the tips of harvested asparagus (Asparagus officinalis L.) spears [King and Davies (1992) Plant Physiol. 100: 1661]. In order to identify factors regulating the postharvest deterioration of asparagus, we have now sequenced the pTIP13 cDNA, derived the encoded amino acid sequence and determined the cellular location of pTIP13 mRNA by in situ hybridization. pTIP13 encodes a derived protein that is rich in proline (22.3%), but also has a high content of lysine (15.2%) and threonine (14.1%). The proline residues are located in motifs at the amino-terminal region of the protein. The carboxyl-terminal region of the derived protein has a high leucine content and shares > 64% amino acid identity with derived proteins identified from cDNA clones to cell wall protein precursor mRNAs obtained from soybean hypocotyls, alfalfa roots, and tomato fruit. Genomic Southern analysis suggests that pTIP13 is encoded by a single-copy gene in asparagus. pTIP13 mRNA was localized to specific cell types in the young bracts of the asparagus spear tip. The results provide new information on the complexity of tissue responses in the tips of asparagus spears following harvest.

The signals controlling the abundance of transcripts up-regulated (pTIP27, pTIP31, and pTIP32) or down-regulated (pTIP20 and pTIP21) after harvest in asparagus (Asparagus officinalis L.) spears were examined. pTIP27 and pTIP31 are known to encode asparagine synthetase (AS) and a beta-galactosidase (beta-gal) homolog, respectively. The nucleotide sequences of pTIP20, pTIP21, and pTIP32 were determined, and they encode histone 3, histone 2B, and an unknown product, respectively. Changes in respiration, soluble sugars, and abundance of the five mRNAs were similar in the tips stored as 30-mm lengths or as part of 180-mm spears. We previously hypothesized that sugars may regulate the level of AS transcripts in asparagus tissue. Asparagus cell cultures were used to test the role of sugar status may regulate the level of AS transcripts in asparagus tissue. Asparagus cell cultures were used to test the role of sugar status in regulating gene expression. Transcript abundance for AS, beta-gal, and pTIP32 was low in cells in sugar-containing medium but increased within 12 h after transferring cells to a sugar-free medium. Histone 3 and histone 2B transcripts were, in general, abundant in cells on sugar-containing medium but declined in abundance when transferred to sugar-free medium. When cells were returned to sugar-containing medium the abundance of transcripts for histone 3 and histone 2B increased, whereas that for AS, beta-gal, and pTIP32 decreased. Soluble sugar levels are known to decline rapidly in the tips of harvested spears. Metabolic regulation by sugar status may have a major influence on gene expression in asparagus spears and other tissue after harvest.

Human neutrophil elastase (NE) stimulates release of neutrophil chemotactic activity by a bronchial epithelial cell line and from nasal epithelial cells. In this article, we show that NE stimulates the production of neutrophil chemotactic activity by 2CFSMEo-cells, a transformed cystic fibrosis bronchial epithelial cell line. The production of chemotactic activity is dose- and time-dependent and can be blocked by preincubation of NE with alpha 1 antitrypsin (alpha1AT). Incubation of the NE-stimulated culture supernatant with neutralizing concentrations of rabbit anti-human interleukin 8 antibody completely neutralizes the chemotactic activity. Transfection of 2CFSMEo- cells with the eukaryotic expression vector pCMV4alpha1AT, complexed to cationic liposomes in a 1:3 wt/wt ratio, results in at least a 10-fold increase in measured human alpha1AT protein in culture supernatant. Detection of human alpha1AT mRNA by reverse transcriptase polymerase chain reaction in total RNA from transfected, but not untransfected cells, confirms successful gene transfer. Compared with untransfected cells, transfer of the human alpha1AT gene decreases chemotactic activity in culture supernatant and prevents cell detachment after NE exposure. Our data indicate that alpha1AT gene transfer is capable of blocking at least some of the biological effects of free elastase on cultured epithelial cells.

The authors present a modification of the Jones Suspension procedure for clawfoot deformity. The specific mechanisms of this deformity are analyzed. The procedure is a split transfer of the extension level with an aggressive clawfoot release and fixation. Recurrence and complications are reduced with the modification.

A computer-controlled adaptive phased array radiofrequency hyperthermia system for improved therapeutic tumor heating is experimentally investigated. Adaptive array feedback techniques are used to modify the electric-field in hyperthermia experiments with a homogeneous saline phantom target. A hyperthermia phased-array antenna system has been modified to implement adaptive nulling and adaptive focusing algorithms. The hyperthermia system is a ring phased-array antenna applicator with four independently controlled RF transmitter channels operating at a CW frequency of 100 MHz. The hyperthermia phased array is made adaptive by software modifications which invoke a gradient-search feedback algorithm that controls the amplitude and phase of each transmitter channel. The gradient-search algorithm implements the method of steepest descent for adaptive nulling (power minimization) and the method of steepest ascent for adaptive focusing (power maximization). The feedback signals are measured by electric-field short-dipole probe antennas. The measured data indicate that with an adaptive hyperthermia array it may be possible to maximize the applied electric field at a tumor position in a complex scattering target body and simultaneously minimize or reduce the electric field at target positions where undesired high-temperature regions (hot spots) occur.

Changes in gene expression and tissue composition were investigated during foliar development and natural senescence of asparagus (Asparagus officinalis L.). Three phases in development and senescence of the foliage were characterized: early fern growth, mature fern, and senescence, when a marked loss of chlorophyll, sucrose, and protein occurred and major changes in translatable mRNAs were detected. Transcripts for three asparagus spear harvest-induced cDNA clones, pTIP9, pTIP11, and pTIP12 (G.A. King and K.M. Davies [1992] Plant Physiol 100: 1661-1669), accumulated during natural foliar senescence, suggesting that the underlying regulatory mechanisms may be similar in both developmental situations. We have used our knowledge of asparagus spear physiology, the probable proteins encoded by the cDNA clones, and our fern development data to propose that sugar depletion regulates the accumulation of at least pTIP12 transcripts in senescing asparagus tissue.

Hairy roots of Brassica napus (rape cv. Giant) have been produced that contain the cytosolic glutamine synthetase (GS) gene from Glycine max (soybean). Leaf explants were cocultivated with Agrobacterium rhizogenes strain A4T harbouring the binary vector pLN16. This vector was constructed by inserting a soybean cytosolic GS cDNA into the multiple cloning site of pGA643, placing it under the control of the CaMV promoter. In addition, the T-DNA region of pLN16 contained a NPTII gene for selection of transformed cells. Transgenic hairy roots grew prolifically on hormone-free media containing a selective level of kanamycin. Southern and northern analyses confirmed the presence of soybean GS DNA and transcripts, respectively. These transformed hairy roots also have a greater abundance of the GS polypeptide, approximately 3-6 fold greater GS activity and lower levels of endogenous ammonia. Hairy roots provide a useful system for studying responses to phosphinothricin (PPT). Hairy roots grown in media containing PPT had lower GS activity, greater ammonia accumulation and slower growth than controls. The presence of the soybean GS gene in the hairy roots reduced these PPT-induced effects and resulted in higher GS activity, lower ammonia levels and faster growth than in PPT-treated controls. Greater tolerance of PPT was also seen in shoots regenerated from the hairy roots displaying elevated levels of GS activity.

We have used pulsed-field gel electrophoresis (PFGE) to test two hypotheses that have been proposed to explain the survival curves with shoulders which are characteristic of low-LET ionizing radiation: (1) Neutral elution studies of the induction of double-strand breaks (DSBs) have suggested that ionizing radiation might induce DSBs in a nonlinear fashion at low doses. (2) Based on analogies to enzyme kinetics, DSB repair might be saturating in the shoulder region. We quantified DSB induction and survival resulting from doses between 0 and 5 Gy spanning the shoulder region of the survival curve. We found that DSB induction was linear at all doses tested down to 0.5 Gy, the limits of sensitivity. Therefore, nonlinear DSB induction cannot account for the shape of the survival curve. To determine whether the DSB repair system was saturated in the shoulder region, we quantified the rate of DSB repair as a function of dose of X rays between 1.25 and 20 Gy. The repair of DSBs was exponential with half-times of repair constant for doses below 10 Gy, and averaged 28 min. We determined the initial rate of repair from the exponential repair kinetics for each dose. The initial rate of repair after radiation treatment increased linearly with dose up to at least 10 Gy. Therefore, saturating DSB repair cannot explain the shoulder of the survival curve.

Purpose: Tumors of the lacrimal sac are rare and have traditionally been treated surgically. We investigated the use of irradiation for treatment., Methods and Materials: Three consecutive patients with primary epithelial cancer of the nasolacrimal apparatus were treated with irradiation. A tumor dose of 52-66 Gy was delivered with conventional fractionation to fields limited to the primary site and immediately surrounding tissues., Results: Local tumor control was achieved in all three patients. Two patients subsequently developed metastatic cervical adenopathy; both were controlled with irradiation to the neck. One of these two died of distant metastases. Two patients are alive and well at 13 years and at 26 months., Conclusion: We conclude that epithelial lacrimal sac tumors are controllable by radiation therapy and with a good cosmetic result. Poorly differentiated lesions require elective cervical nodal irradiation.

A recombinant prostaglandin G/H (PGH) synthase gene has been expressed in vitro in bovine pulmonary artery endothelial cells and in vivo in rabbits by transfection with a plasmid using cationic liposomes. Transfection of bovine pulmonary artery endothelial cells with the PGH synthase cDNA resulted in increased intracellular PGH synthase protein (determined by Western blot analysis) and increased release of prostacyclin. Rabbits intravenously transfected with the PGH synthase gene had increased plasma levels of prostacyclin and PGE2, and their lungs produced increased amounts of the same eicosanoids. In an in situ, perfused preparation of PGH synthase transfected rabbit lungs, the pressor response to endotoxin was markedly attenuated. In addition, pulmonary edema and release of thromboxane B2 into the perfusate after endotoxin infusion were markedly decreased in transfected lungs compared to controls (animals transfected with a pCMV4 construct that did not contain a cDNA insert). The data suggest that augmented endogenous production of prostacyclin and PGE2, achieved by liposome-mediated gene transfer, protects the lungs from endotoxin. This may be caused in part by suppression of endotoxin-stimulated thromboxane B2 production. Modification of lipid mediator responses by in vivo transfection is a potential approach to the therapy of acute lung injury.

This study provided preliminary evidence of the reliability and validity of a set of scales fro rating the parenting behaviors of physically abusive mothers. Thirty-two male and 32 female undergraduates viewed a video-tape of either an abusive or matched control mother interacting with her son. Two tapes of abusive mothers, representative of the Intrusive mother type, and two matched control tapes were used. Subjects rated the mother's behavior on rating scales matching an observational coding system developed by Oldershaw, Walters, and Hall (1989). Mean ratings of between six to eight raters displayed sufficiently high reliability. As expected, ratings correlated with behavior frequency data. Observers' ratings discriminated between abusive mothers and nonabusive controls, providing evidence of construct validity of the scales. The potential utility of a rating scale instrument for the clinical assessment of parenting behaviors is discussed.

A computer-controlled adaptive radio-frequency hyperthermia system for improved therapeutic tumour heating is experimentally investigated. Adaptive array feedback techniques are used to modify the electric-field and temperature distribution in hyperthermia experiments with homogeneous and heterogeneous phantom targets. A commercial hyperthermia phased-array antenna system at the SUNY Health Science Center in Syracuse, New York, has been modified to implement adaptive nulling and adaptive focusing algorithms. The hyperthermia system is the BSD Medical Corporation Model BSD-2000 with Sigma-60 annular phased-array antenna applicator. The transmit phased array system is made adaptive by software modifications which invoke a gradient-search feedback algorithm. The gradient-search algorithm implements the method of steepest descent for adaptive nulling (power minimization) and the method of steepest ascent for adaptive focusing (power maximization). The feedback signals are provided by electric-field short-dipole probe antennas. With an adaptive hyperthermia array using real-time measured data, it may be possible to maximize the applied electric field at a tumour position in a complex scattering target body and simultaneously minimize or reduce the electric field at target positions where undesired high-temperature regions (hot spots) occur. The measured phantom-target data indicate that adaptive nulling can reduce the electric field at one or more target positions while simultaneously focusing the electric field at a deep-seated position within the target.

Optimal management of symptomatic cavernous angiomas (CA) located in the thalamus and the brainstem is problematic. Clinical and radiological (MRI) follow-up series suggest that having hemorrhaged once, recurrent hemorrhage with progressive neurologic dysfunction may commonly occur. We have therefore chosen to treat these lesions when first symptomatic with stereotactic linear radiosurgery (SLR). We now report, after a median follow-up of 27 months, 12 patients with CAs (9 women, 3 men, mean age 40 years) treated in this fashion. Ten patients presented with hemorrhage (3 had more than one hemorrhage): two patients had new onset seizures. All patients had enhanced MRI/MRAs characteristic of CA. There were five brainstem and five thalamic CAs, and one each in the temporal lobe and insula. Cerebral angiograms were done in 8 patients for comparison with their respective MRAs. Only one CA was visualized in the late venous phase on cerebral angiogram and identical vascular features were appreciated on the MRA. The diameter of the CAs ranged from 1.0 to 3.0 cm with a mean of 1.6 cm. Dosimetry planning was based on MRI/CT features and the mean dose at the isocenter was 2.167 cGy (range = 2,000-2,500 cGy) delivered with a mean collimation diameter of 1.46 cm (range = 1.0-2.0 cm). All 12 patients continued to improve neurologically after SLR and had MRI-documented changes in their lesions: in general, the lesions became smaller and signal characteristics converted to methemaglobin. However, 1 patient had an early post-SLR hemorrhage, documented by MRI, at 4.5 months.(ABSTRACT TRUNCATED AT 250 WORDS)

An approach to radiosurgery treatment that can be readily adopted in most radiotherapy centers with linear accelerators is presented. In our institution, a Leksell-type of neurosurgical frame, a computed tomography scanner, locally fabricated cones, and 6 MV X-ray beams are used to perform radiosurgery treatments. Collimated arcs with dose distributions, that conform to the shape of the lesion in the transverse and the sagittal planes are used. It is argued that the uncertainties in the localization of the isocenter within a lesion and the specifications of the size of the target volume do not justify high precision mechanical devices for most radiosurgery treatments.

A full-length cDNA clone (pTIP27) encoding asparagine synthetase (AS; EC 6.3.5.4) was isolated from a cDNA library prepared from the tip section (apex to 30 mm) of Asparagus officinalis L. spears. The cDNA clone encodes an mRNA of 1978 bp, giving a derived protein of 66.5 kD molecular mass. The derived amino acid sequence is 81% homologous to AS from Pisum sativum. Only low levels of transcript for AS could be detected in growing spears, roots, or ferns. However, AS mRNA levels began to increase in the tips of harvested spears after 2 h at 20 degrees C, and in the other sections of the spear after 4 h, suggesting that all sections of the spear were responding to the same postharvest signal. The results are discussed in relation to metabolic changes occurring in harvested spears.

Induction and repair of DNA double-strand breaks (DSBs) was measured using a pulsed-field gel electrophoresis system. A cell line of methotrexate-resistant EMT-6 cells that contain numerous double-minutes (DMs) 3 million base pairs in size was employed. The electrophoretic mobility of these DMs depends on whether they have zero, one, or more than one DSB. With no DSBs the DMs remain as circles and are trapped in the origin of electrophoresis, but with one DSB the DMs migrate as a discrete band and can be detected easily through hybridization with a gene-specific probe. Using a clamped homogeneous electrical field apparatus, the induction of DSBs in the 1.5 to 12 Gy X-ray dose range is studied and is shown to be linear. Double-strand break repair following 7.5 Gy is studied, and is shown to be exponential. The kinetics of both induction and repair of DSBs induced in DM DNA was compared to the induction and repair of DSBs in chromosomal DNA and is shown to be similar. The kinetics of repair of DSBs following 7.5 Gy for cells embedded in agarose and cells in suspension is shown to be similar.

Fifty-three adolescents aged 14 to 18 years with diagnoses of cerebral palsy (n = 27), cleft lip or palate or both (n = 17), or spina bifida (n = 9) took part in this study examining their self-esteem, self-concept, self-acceptance, social self-efficacy, and values, as measured by standardized instruments. Comparisons were made separately for males and females with norms developed for adolescents without disabilities. Significant differences were found only on several aspects of self-concept: females with physical disabilities were lower in perceived social acceptance, athletic competence, and romantic appeal than the normative sample, and males with physical disabilities were lower in perceived scholastic competence, athletic competence, and romantic appeal. In addition, social self-efficacy was found to be a significant predictor of both independence and persistence in adolescents with disabilities, who were significantly less independent and persistent than were normative samples. The discussion focuses on the usefulness of the findings regarding social self-efficacy and the implications of the findings for occupational therapists.

Changes in mRNA activity in tips of harvested asparagus spears (Asparagus officinalis L.) held in light or dark for up to 48 h at 20 degrees C were investigated as an initial step in elucidating the genetic response of asparagus spears to harvest. Total RNA was isolated from 30-mm tips of spears 180 mm in length at 0, 6, 12, 24, and 48 h after spear harvest and translated in vitro, and translation products were separated using both sodium dodecyl sulfate-polyacrylamide gel electrophoresis and two-dimensional polyacrylamide gel electrophoresis. We detected 25 consistent changes in translatable mRNAs, involving both increase and decrease in mRNA abundance. The majority of the changes occurred within 12 h of harvest. Most of the changes were not light regulated. cDNA libraries were constructed from polyadenylated mRNA extracted from tips of spears at harvest (0 h) and after 12 h in the dark at 20 degrees C. Differential hybridization screening of the cDNA libraries isolated nine cDNA clones whose corresponding transcripts had altered expression after harvest. Investigations of mRNA activity during spear development demonstrated that the changes detected were harvest related. Possible roles for the mRNAs corresponding to the isolated clones in tips of harvested spears are discussed.

PAF was administered as an intravenous bolus (0.1 micrograms/kg) to eight chronically instrumented awake sheep. The effects of pretreatment with an inhibitor of cyclooxygenase (meclofenamate) on PAF-induced changes in lung function were compared to those observed with a specific inhibitor of thromboxane synthase (DP1904). Each animal was studied four times in varied order: PAF alone, PAF + DP1904, PAF + meclofenamate, and DP1904 alone. Saline alone (control), DP1904 alone, and meclofenamate alone did not cause changes in any of the measured variables. DP1904 and meclofenamate significantly attenuated the PAF-induced fall in lung compliance, elevation in peak pulmonary artery pressure, and increased lung lymph flow. Both drugs abolished the PAF-induced increases in lung lymph thromboxane B2 concentrations. Meclofenamate, but not DP1904, blocked the rise in lymph 6-keto-PGF1 alpha. Although meclofenamate blocked the rise in lymph PGE2, DP1904 resulted in levels 2.7 times higher than PAF alone. We conclude that: (1) inhibition of thromboxane synthase is as effective as inhibition of cyclooxygenase in attenuating PAF-induced changes in lung function, and (2) thromboxane synthase inhibition results in augmented production of PGE2 following PAF administration in vivo.

Spodoptera frugiperda (Sf9) insect cells were successfully cultured in serum-free medium in a 14-L airlift bioreactor. Cell densities as high as 1 x 10(7) cells/mL were achieved with specific growth rates of approximately 0.0286 h-1 (doubling time of 24 h). This system was also used to demonstrate the expression of a reported gene, beta-galactosidase (beta-gal), when cells were infected with a recombinant baculovirus. Approximately 0.33 mg of beta-gal/mL (i.e., 104,000 units/mL) of medium were obtained at the 14-L scale, while about 0.95 mg of beta-gal/mL (i.e., 285,000 units/mL) of medium were obtained in small-scale shaker flasks. The difference was attributed to a suboptimal infection in the large scale. Specific oxygen consumption rates decreased from 5.58 x 10(-17) mol O2/cell.s in early exponential growth to 3.13 x 10(-17) mol O2/cell.s at 3 days post-infection.

Background: Constriction of small pulmonary arteries and arterioles and focal vascular injury are features of pulmonary hypertension. Because thromboxane A2 is both a vasoconstrictor and a potent stimulus for platelet aggregation, it may be an important mediator of pulmonary hypertension. Its effects are antagonized by prostacyclin, which is released by vascular endothelial cells. We tested the hypothesis that there may be an imbalance between the release of thromboxane A2 and prostacyclin in pulmonary hypertension, reflecting platelet activation and an abnormal response of the pulmonary vascular endothelium., Methods: We used radioimmunoassays to measure the 24-hour urinary excretion of two stable metabolites of thromboxane A2 and a metabolite of prostacyclin in 20 patients with primary pulmonary hypertension, 14 with secondary pulmonary hypertension, 9 with severe chronic obstructive pulmonary disease (COPD) but no clinical evidence of pulmonary hypertension, and 23 normal controls., Results: The 24-hour excretion of 11-dehydro-thromboxane B2 (a stable metabolite of thromboxane A2) was increased in patients with primary pulmonary hypertension and patients with secondary pulmonary hypertension, as compared with normal controls (3224 +/- 482, 5392 +/- 1640, and 1145 +/- 221 pg per milligram of creatinine, respectively; P less than 0.05), whereas the 24-hour excretion of 2,3-dinor-6-keto-prostaglandin F1 alpha (a stable metabolite of prostacyclin) was decreased (369 +/- 106, 304 +/- 76, and 644 +/- 124 pg per milligram of creatinine, respectively; P less than 0.05). The rate of excretion of all metabolites in the patients with COPD but no clinical evidence of pulmonary hypertension was similar to that in the normal controls., Conclusions: An increase in the release of the vasoconstrictor thromboxane A2, suggesting the activation of platelets, occurs in both the primary and secondary forms of pulmonary hypertension. By contrast, the release of prostacyclin is depressed in these patients. Whether the imbalance in the release of these mediators is a cause or a result of pulmonary hypertension is unknown, but it may play a part in the development and maintenance of both forms of the disorder.