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UNLABELLED: The mouse has become the animal of choice for genetic manipulations resulting in altered myocardial function, but assessment of cardiac function is extremely difficult due to the animal's size. This study was designed to establish a work-performing isolated mouse heart preparation to objectively investigate myocardial performance in murine hearts. Isolated work-performing cardiac functional studies were performed on a modified Langendorff apparatus using 15 mice [25 to 28 g, +/-0.4 (SEM)]. The hearts were instrumented with a transonic flow meter and micromanometers to measure on-line aortic flow (AF), aortic pressure, and left atrial pressure (preload). A VAX cardiac function analyzing system was used to determine cardiac parameters including heart rate, contractility (max dP/dt), stroke volume (SV), and stroke work (SW) at various preload levels compared to a baseline preload of 5 mm Hg before and after 7 min of warm ischemia. AF increased from 1.01 ml/min (+/- 0.26) at 5 mm Hg of preload to 4.15 ml/min (+/- 1.03, P < 0.05) at 20 mm Hg of preload and decreased to 3.64 ml/min (+/- 0.62) at 25 mm Hg. SV, dP/dt, and SW increased with higher preload levels. There was a significant decrease in cardiac function postischemia. CONCLUSIONS: A valid isolated work-performing preload-dependent murine heart preparation involving minimal instrumentation of the heart is established to measure cardiac function and myocardial performance. Significant ischemia-reperfusion injury occurred after 7 min of ischemia. This model is a reliable and objective tool by which to evaluate murine cardiac function and to study ischemia-reperfusion injury.
The primary aim of this study was to compare task performance in a laboratory test and real driving performance of outpatients receiving diazepam medication with those of control subjects. Plasma and saliva samples were taken to investigate a level-response relationship. Real driving performance was measured by trained observers. The design of the laboratory test was based on a vigilance task (high attention) directly followed by a simple eye-hand coordination tasks (low attention). Twenty-two males participated in the study. Diazepam was given orally by prescription, mostly as a maintenance dose of 5 mg three times a day. Patients receiving diazepam showed impaired performance in the driving test and the low-attention task. Furthermore, the results indicate no relationship between plasma or saliva levels of diazepam and/or its metabolite N-desmethyldiazepam and real driving performance and/or laboratory task performance.
Out of 1600 sexually inexperienced 28-week old Wistar-Logan male rats 94 sexually inactive ('low performing', LP) and 99 highly active ('high performing', HP) rats were selected. The rats were treated from the 8th month of their life three times a week, subcutaneously, with either 0.9% NaCl or 0.25 mg/kg (-)deprenyl until they died. Their copulatory activity was tested once a week and their learning performance was measured in the shuttle box once in three months. The salt treated LP rats (n = 44) never displayed ejaculation during their life time, they were extremely dull in the shuttle box and lived 134.58 +/- 2.29 weeks. Their (-)deprenyl-treated peers (n = 48) became sexually active, their mating performance was substantially increased and lived 152.54 +/- 1.36 weeks, significantly longer than their salt-treated peers and as long as the salt-treated HP rats. The salt treated HP rats (n = 49) displayed 14.04 +/- 0.56 ejaculations during the first 36-week testing period and due to aging they produced 2.47 +/- 0.23 ejaculations between the 73-108th week of testing. Their learning performance was high. They displayed 78.45 +/- 3.01 conditioned avoidance responses (CAR) during the first 36-week testing period and this dropped to 50.67 +/- 2.99 (p < 0.01) during the 73-108th week of testing. They lived 151.24 +/- 1.36 weeks, significantly (p < 0.001) longer than their LP peers. The (-)depre-nyl-treated HP rats (n = 50) were sexually much more active than their salt-treated peers. They displayed 30.04 +/- 0.85 ejaculations during the first 36-week testing period and 7.40 +/- 0.32 ejaculations between the 73-108th week of testing. Also their learning performance was substantially increased. They produced 113.98 +/- 3.23 CARs during the first 36-week-testing period and 81.68 +/- 2.14 CARs during the 73-108th week of testing. They lived 185.30 +/- 1.96 weeks, significantly more than their salt-treated peers and out of the 50 rats 17 lived longer than the estimated technical life span (TLS).
The consumption of Delta9-tetrahydrocannabinol (THC) as cannabis has been shown to result in impaired and culpable driving. Testing drivers for the presence of THC in blood is problematic as THC and its metabolites may remain in the blood for several days following its consumption, even though the drug may no longer have an influence on driving performance. In the present study, the aim was to assess whether performance on the standardised field sobriety tests (SFSTs) provides a sensitive measure of impaired driving behaviour following the consumption of THC. In a repeated measures design, 40 participants consumed cigarettes that contained either 0% THC (placebo), 1.74% THC (low dose) or 2.93% THC (high dose). For each condition, after smoking a cigarette, participants performed the SFSTs on three occasions (5, 55 and 105 min after the smoking procedure had been completed) as well as a simulated driving test on two occasions (30 and 80 min after the smoking procedure had been completed). The results revealed that driving performance was not significantly impaired 30 min after the consumption of THC but was significantly impaired 80 min after the consumption of THC in both the low and high dose conditions. The percentage of participants whose driving performance was correctly classified as either impaired or not impaired based on the SFSTs ranged between 65.8 and 76.3%, across the two THC conditions. The results suggest that performance on the SFSTs provides a moderate predictor of driving impairment following the consumption of THC and as such, the SFSTs may provide an appropriate screening tool for authorities that wish to assess the driving capabilities of individuals suspected of being under the influence of a drug other than alcohol.
OBJECTIVE: To investigate whether simultaneous cognitive tasks influence maximal motor performance in frail geriatric patients with a history of injurious falls and different levels of cognitive function. DESIGN: Experimental 3-group design. SETTING: Geriatric rehabilitation hospital. PARTICIPANTS: Twenty-two healthy, young adults (mean age +/- standard deviation, 27.7 +/- 9y) and 23 geriatric patients (mean age, 80.9 +/- 5.4y) with a history of injurious falls with (Mini-Mental State Examination [MMSE] score, 20.5 +/- 1.6) and without (MMSE score, 28.1 +/- 1.2) cognitive impairment. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: Motor performance: peak and integral of maximal isometric strength of leg extensors. Cognition: semiautomated calculation steps (serial 2 forward) and nonautomated calculation steps derived from the MMSE (serial 7 retro). Motor and cognitive performances were examined as single and dual tasks. RESULTS: In frail geriatric patients, especially in patients with cognitive impairment, maximal motor performance decreased significantly during all dual tasks. Cognitive performance was reduced, depending on the task and group. CONCLUSION: In frail or cognitively impaired geriatric patients, additional tasks can substantially decrease maximal motor performance. Insufficient resources on dual tasking may thus be a link in connecting the high incidence of falls with frailty and cognitive impairment in geriatric patients with a history of injurious falls.
The purpose of this study was to assess right ventricular (RV) performance during left heart bypass (LHB) and to determine the optimum LHB driving conditions to preserve RV performance. LHB was established with a centrifugal pump in eight mongrel dogs weighing 11-19 kg. Failing heart models were induced by normothermic aortic clamping for 20 min. RV volume was measured by a conductance catheter, and RV performance was evaluated by two parameters. One was the slope of the RV end-systolic pressure-volume relationship (ESPVR) as a load independent index, and the other was the peak RV pressure (PRVP)-RV stroke volume (RVSV) relationship as a "force-velocity relationship." These parameters were measured during varying assist ratios of LHB at 0% to 100% of pulmonary artery flow, and varying afterload as induced by bilateral intrapulmonary balloon inflation. In failing hearts, RV ESPVR showed an inverse correlation, with the assist ratio of LHB significantly decreasing from 4.23 +/- 1.35 (mmHg/ml) to 3.52 +/- 1.30 (mmHg/ml; P < 0.05) after 100% LHB assist. The correlation between PRVP and RVSV also was inversely linear, the slope of this correlation becoming significantly steeper after 100% LHB assist compared to that without LHB (-0.131 +/- 0.042 vs. -0.051 +/- 0.038, P < 0.005). These two slopes intersected, and this intersection was considered the critical point of afterload above which RVSV was decreased by LHB compared to that without LHB. In addition, reducing the assist ratio made the slope of the PRVP-RVSV correlation significantly more gentle (70%: -0.072 +/- 0.037 vs. 100%: -0.131 +/- 0.042, P < 0.05), with the intersection of the two slopes shifting rightward (i.e., higher afterload). Consequently, the critical level of afterload at 70% LHB assist was significantly higher than that at 100% LHB assist (70%: 38.1 +/- 6.9 vs. 100%: 29.2 +/- 6.8, P < 0.05). Therefore, RV performance against afterload was improved by reducing the assist ratio of LHB. This study demonstrates that RV performance is impaired by full LHB assist if the RV afterload is above the critical level, and that reducing the assist ratio may improve RV performance against afterload.
The involvement of service users is extolled in National Service Frameworks and, in Wales, is one of seven standards set out in the National Service Framework for mental health services. National Service Frameworks have an important role in the UK government's performance management strategies. The strategies are retrospective in effect and offer insufficient help for service managers and others seeking to change and improve service performance. Draws on research conducted at intervals over the past four years in Swansea. In today's devolved UK, the details will be different in Wales from elsewhere but the focus is on how a number of organisations with differing responsibilities can work together to manage performance improvement. Demonstrates that change requires leadership to be dispersed across organisational boundaries. Accountability and responsibility must be horizontal and even downwards, not just upwards to government Service users can b e involved in their own care. Surveys that involve service users in their planning stages can gather information about the service issues that matter to them. Managing performance is different from performance management. It can ultimately enable services users to initiate and direct some of the improvements they want to see and to take part in the processes of change. The information systems must be locally useful for all involved, and must offer information about performance in time to affect improvement and change.
CONTEXT: Conventional Papanicolaou (Pap) test slides of high-grade squamous intraepithelial lesions (HSILs) that are frequently misdiagnosed are known to have relatively few dysplastic cells. Whether this is true of cases of HSIL in ThinPrep Pap Test specimens is not known. OBJECTIVE: To determine if cases of HSIL in ThinPrep specimens that are frequently missed have relatively few dysplastic cells. DESIGN: The cytologic features of 16 ThinPrep cases of HSIL that performed poorly in the College of American Pathologists Interlaboratory Comparison Program were compared with 22 ThinPrep Pap Test cases that performed extremely well. RESULTS: Significantly more cases that performed poorly had fewer than 250 dysplastic cells (13/16) than cases that performed well (3/22) (P <.001). CONCLUSION: ThinPrep Pap Test cases with a diagnosis of HSIL that performed poorly in this program had significantly fewer dysplastic cells than those that performed well.
OBJECTIVE: To determine the current state of bedside emergency physician-performed ultrasonography in terms of prevalence, training, quality assurance, and reimbursement at emergency medicine residency programs. METHODS: The link to a 10-question Web-based survey was e-mailed to ultrasound/residency directors at 122 emergency medicine residency programs in the United States. RESULTS: The overall response rate was 84%. Ninety-two percent of programs reported 24-hour emergency physician-performed ultrasonography availability. Fifty-one percent of programs reported that a credentialing/privileging plan was in place at their hospital, and 71% of programs had a quality assurance/image review procedure in place. Emergency medicine specialty-specific guidelines of 150 ultrasonographic examinations and 40 hours of didactic instruction were met by 39% and 22% of residencies, respectively, although only 13.7% of programs were completing the 300 examinations recommended by the American Institute of Ultrasound in Medicine. Sixteen programs (16%) reported that they were currently billing for emergency physician-performed ultrasonography; of those not billing, 10 (12%) planned to bill within 1 year, and 32 (37%) planned to bill at some point in the future. CONCLUSIONS: Performance and training in emergency physician-performed ultrasonography at academic medical centers continues to increase. The number of emergency medicine residency programs meeting specialty-specific guidelines has more than doubled in the last 4 years, but only a small number are meeting American Institute of Ultrasound in Medicine guidelines. Although only 16% of programs reported that they were currently billing for emergency physician-performed ultrasonography, most had plans to bill in the future.
The purpose of this study was to determine to what extent admission criteria predict graduate school and career performance. The study also analyzed which objective and subjective criteria served as the best predictors. MHA graduates of the University of Minnesota from 1974 to 1977 were surveyed to assess career performance. Student files served as the data base on admission criteria and program performance. Career performance was measured by four variables: total compensation, satisfaction, fiscal responsibility, and level of authority. High levels of MHA program performance were associated with women who had high undergraduate GPAs from highly selective undergraduate colleges, were undergraduate business majors, and participated in extracurricular activities. High levels of compensation were associated with relatively low undergraduate GPAs, high levels of participation in undergraduate extracurricular activities, and being single at admission to graduate school. Admission to MHA programs should be based upon both objective and subjective criteria. Emphasis should be placed upon the selection process for MHA students since admission criteria are shown to explain 30 percent of the variability in graduate program performance, and as much as 65 percent of the variance in level of position authority.
This study assessed relationships between academic performance in dental school and "first attempt" performance on a state dental licensure examination for 1996-2003 graduates from the University of Florida College of Dentistry (UFCD). The 524 graduates were ranked into quartiles based on graduating GPA. Using analysis of variance (ANOVA), the students' mean exam score (or exam section score) for each respective quartile (n=131) was compared with mean score for graduates in the combined four quartiles (n=524). ANOVA assessments, by quartile, were performed for the following six measures: 1) overall composite score on the dental licensure exam, 2) clinical periodontics section, 3) clinical amalgam section, 4) combination of clinical periodontics and clinical amalgam, 5) laboratory (manikin exam) with a written prosthodontic exam, and 6) manikin exam without the prosthodontic exam. For the overall exam and all exam sections, a significant (p<0.001) relationship was found between higher mean exam scores and academic ranking in quartile 1. A significant relationship was found between performance (lower mean scores) and ranking in quartile 4 for all exam sections, with the exception of the clinical periodontal section. The results of this study indicate a correlation between performance in dental school and performance on the Florida dental licensure exam for 1996-2003 UFCD graduates.
Primary care physicians perform simple laboratory tests in clinical practice, frequently with little formal training. To determine the frequency of tests that are performed and evaluate house officer laboratory skills, we surveyed house officer attitudes and tested their ability to perform four common laboratory tests. We received 193 responses from 254 house officers at one university teaching hospital. While most perceived the need to use ward laboratories (ie, self-service laboratories located on patient care wards), 67% used them infrequently. Barriers included poor laboratory condition, inadequate time, accuracy, and infectious exposure concerns. Twenty-four percent felt they did not know or were unsure if they knew how to perform simple tests. Forty-seven house officers completed the practical examination. Most accurately reported a spun hematocrit and correctly identified white blood cell findings on a blood smear. Only 50% counted 100 cells. Urinary dipstick interpretation was generally acceptable but the microscopic examination was less accurate. Twenty-three percent failed to identify gram-negative rods on a slide with both gram-positive cocci and gram-negative rods. If physicians are to perform selected laboratory tests, these data suggest, at least in one institution, more formal training, practice, and evaluation are necessary to ensure their performance with adequate proficiency.
In rodents, ethanol produces a greater impact on the ability to perform spatial reference memory tasks than nonspatial reference memory tasks. Such evidence may reflect a selective disruption in the use of previously acquired spatial information. However, a nonmnemonic explanation has yet to be ruled out Tasks used to study ethanol's effects on spatial memory commonly require subjects to utilize distal, or extramaze, cues to respond correctly. In contrast, many previously used nonspatial tasks could be solved using cues located on the maze itself. Because ethanol has been shown to disrupt sensory processing, it is possible that previously observed differences in the effects of ethanol on spatial and nonspatial performance were actually due to differences in the proximity of relevant cues in the spatial and nonspatial tasks and not to a selective disruption in spatial memory. The present study compares the effects of ethanol on the performance of spatial and nonspatial reference memory tasks that require subjects to discriminate among extramaze cues for correct responding. Subjects were trained while sober to navigate to a goal arm on a 12-arm maze. In the spatial task, the goal arm was defined by its location with respect to a number of extramaze cues. In the nonspatial task, the goal arm was defined by the presence of a single extramaze cue located directly beyond the end of the arm. Subjects were tested under 1 of 4 doses of ethanol (0.0, 0.7, 1.4, and 2.1 g/kg). Performance on the nonspatial task was more resistant to the effects of ethanol than performance on the spatial task. The results suggest that differences in the effects of ethanol on spatial and nonspatial performance are not due to differences in the proximity of relevant cues in previously used spatial and nonspatial tasks.
The purpose of the present study was to investigate the fatigue effect of repeated exhaustive stretch-shortening cycle (SSC) exercise on concentric muscle function. Ten healthy male subjects performed SSC exercise [92 (30) jumps] on a special sledge apparatus. Exhaustion occurred on average within 3 min. A squat jump (SJ) test utilizing a concentric-only action was performed immediately before and after the SSC exercise, and then 10 min, 20 min, 2 days and 4 days later. In addition, a drop jump (DJ) test using an SSC was also performed immediately before and 20 min after the SSC exercise, and 2 days and 4 days later. During jump tests, lower limb joint moment, power, and work contributions were analyzed by using the kinetic and kinematic data. The fatigue exercise was characterized by a relatively high blood lactate concentration [7.2 (0.8) mmol x l(-1)] and a 2-day delayed increase in serum creatine kinase activity [486 (300) U x l(-1)]. SJ performance decreased markedly immediately after the SSC exercise (P<0.05) and then recovered within 10 min. In contrast, DJ performance and knee joint contribution showed a delayed decrease 2 days after the SSC exercise bout. The surface electromyographic (EMG) activity of the lower limb muscles showed no obvious change in the SJ in comparison to the DJ, although in the latter there was a delayed decrease of knee extensor EMG during the pre-activation and braking phases. The results suggest that isolated concentric muscle function is affected mainly by acute metabolic fatigue after SSC exercise. During a follow-up period after the exercise, changes in hip and knee joint contribution in SJ showed a different recovery pattern compared to those in eccentric DJ. It could be suggested that exhaustive SSC exercise would mainly influence the relative power-work balance between the hip and knee joints during the eccentric phase of SSC. Thus different motor control strategies may account for the distinctive fatigue responses observed in SJ and DJ.
A new protocol for Structured Observation of Motor Performance in Infants, SOMP-I, designed to describe both progress and quality of motor performance, was evaluated concerning its ability to describe and to discriminate between the motor performance observed in different groups of infants. Sixty-eight infants born at < 32 completed weeks (c.w.) of gestation formed group I, 81 infants born at 32-37 c.w. group II and 77 infants born at > 37 c.w. group III. Seventy-two neonatally healthy full term infants served as controls (group IV). The detailed assessment of level (progress) of motor development at 0, 2, 4, 6 and 10 months of age corrected for preterm birth disclosed few differences in mean level between the groups. Most were found between group I and the control group. In contrast, the quality of motor performance, expressed as proportion of infants with deviations, type of deviation, and total number of deviations per infant, showed many differences, especially between groups I and III, respectively, and the control group. Thus, the SOMP-I protocol permits a detailed assessment both of the level of motor development and the quality of motor performance but has a better discriminative ability for the latter.
The aim of the study was to estimate the sensitivity of a brief self-paced visual search task to increased levels of sleepiness as a consequence of 40 h of sleep deprivation. Time-of-day effects on this task, on subjective sleepiness and on oculomotor performance changes, were also assessed. Eight normal subjects slept for three nights in the laboratory (adaptation, baseline, recovery). Baseline and recovery nights were separated by a period of 40 h of continuous wakefulness, during which subjects were tested every 2 h from 10:00 to 22:00 h on both days preceding and following the sleep deprivation night, as well as from 24:00 to 08:00 h during the deprivation period. At the same time, subjects filled in a visual analogue sleepiness scale and the Stanford Sleepiness Scale (SSS). As regards cognitive performance, significant effects were found on speed measures, while accuracy was not affected. The number of explored rows was higher after the baseline night than after the sleepless night, and showed a consistent time-of-day trend. Omissions ratio (OR), false positives ratio (FPR) and hits ratio (HR) did not show any significant effect. Subjective ratings of sleepiness varied according to speed measures, being affected by sleep deprivation and time of day. Since similar effects were found with an oculomotor task, detrended functions for all variables across the 40 h of continuous wakefulness were calculated. A circadian effect was found, in which speed measures seem to be more affected than accuracy ones in both visual search and oculomotor tasks. It is concluded that 40 h of prolonged wakefulness significantly impairs performance in a brief cognitive visual search task. Such a performance worsening is evident on speed, but not on accuracy indices, and is strictly related to the deterioration of oculomotor performance, indicating a clear circadian effect.
In the present study we tested the hypothesis that learned irrelevance underlies the frequently observed poor performance of Parkinson's disease (PD) patients on card sorting tests. If learned irrelevance accounts for the poor performance of PD patients on card sorting tests, PD patients and control subjects (CS) will not differ in the acquisition phase, during which basic concept formation is assessed, but they will differ in the subsequent shifting phases. We presented three distinct card sorting tests with an identical format to 51 PD patients and 24 normal controls. The groups did not differ with respect to intelligence, memory, or attention. PD patients showed a slightly better performance in the acquisition phase. In the first shifting phase, the performance of PD patients was significantly poorer than that of control subjects after correction for basic concept formation. In the second shifting phase this difference disappeared. We conclude that learned irrelevance does not account for the poor performance of PD patients in card sorting tests. The results are discussed in terms of self-generation of problem solving strategies.