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The recovery of structure from motion in real time over extended areas demands methods that mitigate the effects of computational complexity and arithmetical inconsistency. In this paper, we develop SCISM, an algorithm based on relative frame bundle adjustment, which splits the recovered map of 3D landmarks and keyframes poses so that the camera can continue to grow and explore a local map in real time while, at the same time, a bulk map is optimized in the background. By temporarily excluding certain measurements, it ensures that both maps are consistent, and by using the relative frame representation, new results from the bulk process can update the local process without disturbance. The paper first shows how to apply this representation to the parallel tracking and mapping (PTAM) method, a real-time bundle adjuster, and compares results obtained using global and relative frames. It then explains the relative representation's use in SCISM and describes an implementation using PTAM. The paper provides evidence of the algorithm's real-time operation in outdoor scenes, and includes comparison with a more conventional submapping approach.

Background: Anabolic steroids have been reported to improve wound healing., Objective: To determine whether oxandrolone increases the percentage of target pressure ulcers (TPUs) that heal compared with placebo and whether healed ulcers remain closed 8 weeks after treatment., Design: Parallel-group, placebo-controlled, randomized trial conducted from 1 August 2005 to 30 November 2008. Patients, clinical care providers, study personnel, and statisticians were blinded to treatment assignment. (ClinicalTrials.gov: NCT00101361)., Setting: 16 inpatient spinal cord injury (SCI) services at Veterans Affairs medical centers., Patients: 1900 prescreened, 779 screened, and 212 randomly assigned inpatients with SCI and stage III or IV TPUs., Intervention: Oxandrolone, 20 mg/d (n = 108), or placebo (n = 104) until the TPU healed or 24 weeks., Measurements: The primary outcome was healed TPUs. The secondary outcome was the percentage of TPUs that remained healed at 8-week follow-up., Results: 24.1% (95% CI, 16.0% to 32.1%) of TPUs in oxandrolone recipients and 29.8% (CI, 21.0% to 38.6%) in placebo recipients healed (difference, -5.7 percentage points [CI, -17.5 to 6.8 percentage points]; P = 0.40). At 8-week follow-up, 16.7% (CI, 9.6% to 23.7%) of oxandrolone recipients and 15.4% (CI, 8.5% to 22.3%) of placebo recipients retained a healed TPU (difference, 1.3 percentage points [CI, -8.8 to 11.2 percentage points]; P = 0.70). No serious adverse events were related to oxandrolone. Liver enzyme levels were elevated in 32.4% (CI, 23.6% to 41.2%) of oxandrolone recipients and 2.9% (CI, 0.0% to 6.1%) of placebo recipients (P < 0.001)., Limitations: Selection of severe wounds may have reduced treatment response. Approximately one third of patients did not complete the study in the treatment and placebo groups. The study was terminated after a futility analysis showed a low probability of detecting a significant difference between the groups., Conclusion: Oxandrolone showed no benefit over placebo for improving healing or the percentage of TPUs that remained closed after 8 weeks of treatment., Primary Funding Source: U.S. Department of Veterans Affairs.

The authors examined whether the top-down requirements of dissociating the spatial relations between stimulus and response in a goal-directed grasping task renders the mediation of aperture trajectories via relative visual information. To address that issue, participants grasped differently sized target objects (i.e., grasping condition) and also grasped to a location that was dissociated from the target object (i.e., pantomime-grasping condition). Just noticeable difference (JND) values associated with the early through late stages of aperture shaping were computed to examine the extent to which motor output adhered to, or violated, the psychophysical principles of Weber's law. As expected, JNDs during the late stages of the grasping condition violated Weber's law: a result evincing the use of absolute visual information. In contrast, JNDs for the pantomime-grasping condition produced a continuous adherence to Weber's law. Such a result indicates that dissociating a stimulus from a response is a perception-based task and results in aperture shaping via relative visual information.

The "just noticeable difference" (JND) represents the minimum amount by which a stimulus must change to produce a noticeable variation in one's perceptual experience (i.e., Weber's law). Recent work has shown that within-participant standard deviations of grip aperture (i.e., JNDs) increase linearly with increasing object size during the early, but not the late, stages of goal-directed grasping. A visually based explanation for this finding is that the early and late stages of grasping are respectively mediated by relative and absolute visual information and therefore render a time-dependent adherence to Weber's law. Alternatively, a motor-based explanation contends that the larger aperture shaping impulses required for larger objects gives rise to a stochastic increase in the variability of motor output (i.e., impulse-variability hypothesis). To test the second explanation, we had participants grasp differently sized objects in grasping time criteria of 400 and 800 ms. Thus, the 400 ms condition required larger aperture shaping impulses than the 800 ms condition. In line with previous work, JNDs during early aperture shaping (i.e., at the time of peak aperture acceleration and peak aperture velocity) for both the 400 and 800 ms conditions scaled linearly with object size, whereas JNDs later in the response (i.e., at the time of peak grip aperture) did not. Moreover, the 400 and 800 ms conditions produced comparable slopes relating JNDs to object size. In other words, larger aperture shaping impulses did not give rise to a stochastic increase in aperture variability at each object size. As such, the theoretical tenets of the impulse-variability hypothesis do not provide a viable framework for the time-dependent scaling of JNDs to object size. Instead, we propose that a dynamic interplay between relative and absolute visual information gives rise to grasp trajectories that exhibit an early adherence and late violation to Weber's law.

Objective: To examine whether supported employment (SE) is more effective than treatment as usual (TAU) in returning veterans to competitive employment after spinal cord injury (SCI)., Design: Prospective, randomized, controlled, multisite trial of SE versus TAU for vocational issues with 12 months of follow-up data., Setting: SCI centers in the Veterans Health Administration., Participants: Subjects (N=201) were enrolled and completed baseline interviews. In interventional sites, subjects were randomly assigned to the SE condition (n=81) or the TAU condition (treatment as usual-interventional site [TAU-IS], n=76). In observational sites where the SE program was not available, 44 subjects were enrolled in a nonrandomized TAU condition (treatment as usual-observational site [TAU-OS])., Interventions: The intervention consisted of an SE vocational rehabilitation program called the Spinal Cord Injury Vocational Integration Program, which adhered as closely as possible to principles of SE as developed and described in the individual placement and support model of SE for persons with mental illness., Main Outcome Measures: The primary study outcome measurement was competitive employment in the community., Results: Subjects in the SE group were 2.5 times more likely than the TAU-IS group and 11.4 times more likely than the TAU-OS group to obtain competitive employment., Conclusions: To the best of our knowledge, this is the first and only controlled study of a specific vocational rehabilitation program to report improved employment outcomes for persons with SCI. SE, a well-prescribed method of integrated vocational care, was superior to usual practices in improving employment outcomes for veterans with SCI., (Copyright © 2012 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.)

Opportunities to directly study infrequent forest disturbance events often lead to valuable information about vegetation dynamics. In mesic temperate forests of North America, stand-replacing crown fire occurs infrequently, with a return interval of 2000-3000 years. Rare chance events, however, may have profound impacts on the developmental trajectories of forest ecosystems. For example, it has been postulated that stand-replacing fire may have been an important factor in the establishment of eastern hemlock (Tsuga canadensis) stands in the northern Great Lakes region. Nevertheless, experimental evidence linking hemlock regeneration to non-anthropogenic fire is limited. To clarify this potential relationship, we monitored vegetation dynamics following a rare lightning-origin crown fire in a Wisconsin hemlock-hardwood forest. We also studied vegetation in bulldozer-created fire breaks and adjacent undisturbed forest. Our results indicate that hemlock establishment was rare in the burned area but moderately common in the scarified bulldozer lines compared to the reference area. Early-successional, non-arboreal species including Rubus spp., Vaccinium angustifolium, sedges (Carex spp.), grasses, Epilobium ciliatum, and Pteridium aquilinium were the most abundant post-fire species. Collectively, our results suggest that competing vegetation and moisture stress resulting from drought may reduce the efficacy of scarification treatments as well as the usefulness of fire for preparing a suitable seedbed for hemlock. The increasing prevalence of growing-season drought suggests that silvicultural strategies based on historic disturbance regimes may need to be reevaluated for mesic species.

An exemplar metric of goal-directed grasping (i.e., peak grip aperture) has been shown to be refractory to a psychophysical principle governing visuoperceptual estimations of object size (i.e., Weber's law). This dissociation suggests that vision for action and vision for perception are mediated by absolute and relative visual information, respectively. The present investigation examined whether aperture shaping elicits a unitary or process-dependent violation of Weber's law. Participants grasped differently sized objects (20, 30, 40, 50 and 60 mm of width) and just noticeable difference (JND) scores related to grip aperture were computed at the time of peak grip aperture as well as at normalized deciles of the response (i.e., 10-90% of grasping time). JNDs during the early and middle stages of the trajectory scaled to object size whereas values late in the trajectory (>50% of grasping time and including the time of peak grip aperture) did not. Thus, results show an early, but not late, adherence to Weber's law and indicate that movement planning and movement control are supported via relative and absolute visual information, respectively., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

The authors examined whether the diminished online control of antisaccades is related to a trade-off between movement planning and control or the remapping of target properties to a mirror-symmetrical location (i.e., vector inversion). Pro- and antisaccades were examined in a standard no-delay schedule wherein target onset served as the movement imperative and a delay cuing schedule wherein responses were initiated 2,000 ms following target onset. Importantly, the delay cuing schedule was employed to equate pro- and antisaccade reaction times. Online control was evaluated by indexing the strength of trajectory amendments at normalized increments of movement time. Antisaccades exhibited fewer online corrections than prosaccades, and this result was consistent across cuing schedules. Thus, the diminished online control of antisaccades cannot be tied to a trade-off between movement planning and control. Rather, the authors propose that the intentional nature of dissociating stimulus and response (i.e., vector inversion) engenders a slow mode of cognitive control that is not optimized for fast oculomotor corrections.

Background: Chronic pain is a significant problem for many individuals following spinal cord injury (SCI). Unfortunately, SCI-related neuropathic pain has proven to be largely refractory to analgesic medications and other available treatments. Cranial electrotherapy stimulation (CES) has been effective in managing some types of pain. It involves the application of a small amount of current through the head via ear clip electrodes., Objective: Explore the effectiveness of CES for neuropathic pain in persons with SCI and chronic pain., Study Design: Multi-site, double-blind, sham-controlled study., Participants: Adults with SCI and chronic neuropathic pain at or below the level of injury were randomized to receive active or sham CES., Intervention: Application of active CES or sham CES 1 hour daily for 21 days. Six-month open-label phase to assess 'as-needed' CES use., Outcome Measures: Change in pre- to post-session pain ratings as well as change in pain intensity, pain interference, pain quality, pain beliefs and coping strategies, general physical and mental health status, depressive symptomatology, perceived stress, and anxiety pre- to post-treatment., Results: The active group reported a significantly greater average decrease in pain during daily treatments than the sham group (Kruskal-Wallis chi-square = 4.70, P < 0.05). During the 21-day trial, there was a significant group × time interaction for only one outcome variable; the active group showed larger pre- to post-treatment decreases in pain interference than the sham group did (F = 8.50, P < 0.01, d = 0.59)., Conclusions: On average, CES appears to have provided a small but statistically significant improvement in pain intensity and pain interference with few troublesome side effects. Individual results varied from no pain relief to a great deal of relief.

Objectives: Few empirical studies have examined the disaster preparedness and response practices of individuals with spinal cord injuries and/or disorders (SCI/D) and the healthcare providers who serve them. This study was conducted to understand the experiences of Veterans Health Administration (VHA) providers and Veterans with SCI/D in recent natural disasters, and to identify lessons learned for disaster preparedness and response in the context of SCI/D., Design: Semi-structured interviews were conducted with providers and Veterans recruited through seven VHA facilities that had sustained a disaster since 2003. Audio recordings of the interviews were transcribed; transcripts were analyzed using constant comparative techniques., Results: Forty participants completed an interview, including 21 VHA SCI/D providers and 19 Veterans with SCI/D. Disasters experienced by participants were weather related. While many Veterans were evacuated or admitted to nearby VHA facilities, others chose to stay in their communities. All facilities had formal disaster plans and engaged in related training; however, participants explained that many aspects of a response take shape 'in the moment,' and must address both provider and Veteran needs. Dispersion of resources hindered well-coordinated care, but effective communication, teamwork, advanced warnings, and VHA's electronic medical record facilitated efforts., Conclusions: Even in the case of thorough planning, Veterans with SCI/D and their healthcare providers are faced with pressing needs during disasters, and identifying strategies to coordinate care is critical. The lessons learned are intended to inform the efforts of healthcare providers who may be involved in the care of individuals with SCI/D in future disasters.

Objective: To test the efficacy and safety of a cannabinoid, dronabinol, compared with an active control, diphenhydramine, in relieving neuropathic pain in persons with spinal cord injury., Design: A randomized, controlled, double-blind, crossover pilot study., Results: Seven adults with spinal cord injury and neuropathic pain below the level of injury participated. Two participants withdrew while receiving dronabinol, their first medication. For the remaining five participants, change in pain on a scale of 0-10 from baseline to the end of the maintenance phase did not differ significantly between the two medications (mean change, dronabinol: 0.20 ± 0.837, range = -1.00 to 1.00; diphenhydramine: -1.80 ± 2.490, range = -6.00 to 0; Wilcoxon Z = 1.63, P = 0.102). Similar results were found when the average of the two ratings during the maintenance phase was used (dronabinol: -0.20 ± 0.671, range = -0.50 to 1.00; diphenhydramine: -1.40 ± 1.245, range = -3.50 to -0.50; Wilcoxon Z = 1.60, P = 0.109). The most common side effects were dry mouth, constipation, fatigue, and drowsiness for both medications., Conclusions: On average, dronabinol was no more effective than diphenhydramine for relieving chronic neuropathic pain below the level of injury.

This paper develops a Square Root Unscented Kalman Filter (SRUKF) for performing video-rate visual simultaneous localization and mapping (SLAM) using a single camera. The conventional UKF has been proposed previously for SLAM, improving the handling of nonlinearities compared with the more widely used Extended Kalman Filter (EKF). However, no account was taken of the comparative complexity of the algorithms: In SLAM, the UKF scales as O(N;{3}) in the state length, compared to the EKF's O(N;{2}), making it unsuitable for video-rate applications with other than unrealistically few scene points. Here, it is shown that the SRUKF provides the same results as the UKF to within machine accuracy and that it can be reposed with complexity O(N;{2}) for state estimation in visual SLAM. This paper presents results from video-rate experiments on live imagery. Trials using synthesized data show that the consistency of the SRUKF is routinely better than that of the EKF, but that its overall cost settles at an order of magnitude greater than the EKF for large scenes.

Objective: To test the hypothesis that enhanced education and structured follow-up after pressure ulcer surgery will result in fewer recurrences., Design: Randomized controlled trial., Setting: Veterans Affairs medical center., Participants: Forty-nine veteran men with spinal cord injury or dysfunction were approached on admission for pressure ulcer surgery. Five never had surgery, 2 refused to participate, and one withdrew. Forty-one were randomized into 3 groups. Three participants' ulcers did not heal, so follow-up could not begin., Interventions: Group 1 received individualized pressure ulcer education and monthly structured telephone follow-up (n=20); group 2 received monthly mail or telephone follow-up without educational content (n=11); and group 3 received quarterly mail or telephone follow-up without educational content (n=10). Follow-up continued until recurrence, death, or 24 months., Main Outcome Measure: Time to pressure ulcer recurrence., Results: Group 1 had a longer average time to ulcer recurrence or end of study than groups 2 and 3 (19.6 mo, 10.1 mo, 10.3 mo; P=.002) and had a smaller rate of recurrence (33%, 60%, 90%; P=.007). Survival analysis confirmed these findings (P=.009)., Conclusions: Individualized education and structured monthly contacts may be effective in reducing the frequency of or delaying pressure ulcer recurrence after surgical repair of an ulcer.

Background/objective: To predict recurrence of pressure ulcers (PrUs) in a high-risk population of veterans with spinal cord injury (SCI)., Design: Cross-sectional observational design., Participants: A convenience sample of 64 subjects from 6 Department of Veterans Affairs (VA) SCI Centers who had been admitted to the hospital for the treatment of stage III-IV pelvic PrUs and were healed at the time of discharge back to the community., Main Outcome Measures: Primary outcome measures were pelvic PrU recurrence, defined as self-reported new skin breakdown (stage II or greater) in the pelvic area (not necessarily in the same location as previous ulcer) and time to recurrence., Results: There were no differences between those with/without recurrences with regard to age, age at/level of injury, number of previous ulcers or surgery, rate of or time, to recurrence. Mean age was 56 years; most were white and men, lived at home, and had some college education. Mean time since SCI was 22 years; 28% had tetraplegia; mean number of prior pressure ulcers was 3; and almost one half had a previous ulcer in the same location. The strongest predictor of recurrence in a multivariate logistic regression was African American race (odds ratio = 9.3). Additional predictors included higher scores on the Charlson Co-Morbidity Index (indicating a higher burden of illness), the Salzburg PrU Risk Assessment Scales, and longer sitting time at discharge., Conclusion: Identifying individuals at highest risk for recurrence and developing effective prevention programs are essential rehabilitation goals. We recommend that the unique findings of this exploratory study be considered preliminary until replication of these results is published.

Objective: To test the hypotheses that both amitriptyline and gabapentin are more effective in relieving neuropathic pain than an active placebo, diphenhydramine., Design: Randomized, controlled, double blind, triple crossover 8-week trial., Setting: Veterans Affairs medical center., Participants: Community dwelling adults with spinal cord injury (N=38) were recruited by telephone, letters, and flyers., Intervention: Eight-week trial each of amitriptyline, gabapentin, and diphenhydramine., Main Outcome Measures: Pain intensity measured with a 10-cm visual analog scale (VAS) and an 11-point (0-10) numeric rating scale (NRS) and depressive symptomatology measured with the Center for Epidemiologic Studies Depression Scale-Short Form (CESD-SF)., Results: Baseline VAS scores for participants with low (< 10) CESD-SF scores was 4.61 and for those with high scores (> or = 10) it was 7.41. At week 8, in participants with high baseline CESD-SF scores, amitriptyline (mean, 4.21) was more effective than diphenhydramine (mean, 6.67; P=.035), and there was a nonsignificant trend suggesting that amitriptyline may be more effective than gabapentin (mean, 6.68; P=.061). Gabapentin was no more effective than diphenhydramine (P=.97). There was no significant difference among the medications for those with lower CESD-SF scores. Results could not be attributed to dropout rates, order or dose of medications, amount of medication taken for breakthrough pain, or side effects., Conclusions: Amitriptyline is more efficacious in relieving neuropathic pain than diphenhydramine at or below the level of spinal cord injury in people who have considerable depressive symptomatology.

Background: The objective of our study was to evaluate the outcomes of open-heart surgery in patients with a spinal cord injury., Methods: A retrospective analysis of all patients (n = 8) with a spinal cord injury who underwent open-heart operations in a single institution from April 1994 to November 2006 was conducted., Results: All patients had a permanent spinal cord injury with levels ranging from T3 to L2 with a mean age of 62 years (range, 47-72). Seven coronary artery bypass operations and 2 aortic valve replacements were performed. The mean cardiac ejection fraction was 44% (range, 20-60). Seventy-five percent of the patients were extubated within 24 hours of the operation. A decubitus ulcer occurred in only 1 patient. The acute hospital stay averaged 14 days (range, 6-36). One patient died from multiorgan failure on postoperative day 13 giving an in-hospital 30-day mortality of 12.5%. The 5-year survival was 75% with a mean follow-up of 67 months (range, .5-129)., Conclusions: Open-heart operations in patients with a spinal cord injury can be performed safely with acceptable early and late outcomes.

Objective: To describe the challenges of conducting a large randomized controlled trial (RCT) to assess the effectiveness of an intervention to prevent recurrent pressure ulcers among a high-risk population of subjects with spinal cord injury (SCI)., Design: Prospective multisite, randomized design comparing outcomes of patients who received individualized education and structured telephone counseling follow-up with those of patients receiving customary care. This study was stopped early because of unanticipated recruitment problems., Setting: Six Veterans Affairs SCI specialty centers., Participants: Veterans (N=150) treated for stage III or IV pelvic pressure ulcers., Interventions: Not applicable., Main Outcome Measure: Recurrence (defined as new skin breakdown in the pelvic area) and time to recurrence. The study was stopped early because of slow recruitment, so the focus of this study is lessons learned, not the main planned outcome measures., Results: Subject recruitment did not meet original expectations because almost 50% of those enrolled left the hospital with the study ulcer unhealed (having a healed ulcer was a requirement for participation). No significant differences were observed between groups on rate of or time to recurrence at the time the study was stopped. Among the 6 sites, variability in ulcer management (eg, length of stay, receipt of medical vs surgical treatment, sitting tolerance before discharge) and time to recurrence (median, 4mo) were observed., Conclusions: RCTs in real-world settings are the most robust method of assessing the effectiveness of prevention strategies. However, in complex, rapidly changing health care organizations, blinding is infeasible, it may be impractical to control for every variable that influences a study's outcome, and any assumptions that usual care is static are probably mistaken. Investigators must be prepared to use innovative approaches to maintain the integrity of the study design, including flexibility in inclusion and exclusion criteria to support accrual, obtaining a better understanding of the important aspects of usual care that may need to be standardized, continuous improvement within the intervention arm, and anticipation and minimization of risks from organizational changes. With attention to these delivery system issues and the usual design features of randomized trials, we believe real-world care settings can serve as important laboratories to test pressure ulcer prevention strategies in this population.

This study employed neurophysiological methods to relate the condition of the corticospinal system with the voluntary control of lower-limb muscles in persons with motor-incomplete spinal cord injury. It consisted of two phases. In a group of ten healthy subjects, single and paired transcranial magnetic stimulation (TMS) of the motor cortex was used to study the behavior of the resulting motor evoked potentials (MEP) in lower-limb muscles. Interstimulus intervals (ISIs) of 15-100 ms were examined for augmentation of test MEPs by threshold or subthreshold conditioning stimuli. The second phase of this study examined eight incomplete spinal cord injured (iSCI) subjects, American Spinal Injury Association Impairment Scale C (n = 5) and D (n = 3) in whom voluntary motor control was quantified using the surface EMG (sEMG) based Voluntary Response Index (VRI). The VRI is calculated to characterize relative output patterns across ten lower-limb muscles recorded during a standard protocol of elementary voluntary motor tasks. VRI components were calculated by comparing the distribution of sEMG in iSCI subjects with prototype patterns collected from 15 healthy subjects using the same rigidly administered protocol, The resulting similarity index (SI) and magnitude values provided the measure of voluntary motor control. Corticospinal system connections were characterized by the thresholds for MEPs in key muscles. Key muscles were those that function as the prime-movers, or agonists for the voluntary movements from which the VRI data were calculated. Results include healthy-subject data that showed significant increases in conditioned MEP responses with paired stimuli of 15-50 ms ISI. Stimulus pairs of 75 and 100 ms showed no increase in MEP peak amplitude over that of the single-pulse conditioning stimulus alone, usually no response. For the iSCI subjects, 42% of the agonists responded to single-pulse TMS and 25% required paired-pulse TMS to produce an MEP. American Spinal Injury Association Impairment Scale component motor scores for agonist muscles, Quadriceps, Tibialis Anterior, and Triceps Surae, were significantly lower where MEPs could not be obtained (p < 0.05). VRI values were also significantly lower for motor tasks with agonists that had no resting MEP (p < 0.01). Therefore, the presence of a demonstrable connection between the motor cortex and spinal motor neurons in persons with SCI was related to the quality of post-injury voluntary motor control as assessed by the VRI.

Study Design: Cross-sectional retrospective study of a neurophysiological method of voluntary motor control characterization., Objectives: This study was undertaken to validate the surface electromyography (sEMG)-based voluntary response index (VRI) as an objective, quantitative, laboratory measure of spinal cord injury severity in terms of voluntary motor control disruption., Setting: VA Medical Centers in Houston and Dallas Texas, USA., Methods: A total of 67 subjects with incomplete spinal cord injury (iSCI), American Spinal Injury Association Impairment Scale (AIS)-C (n = 32) and -D (n = 35) were studied. sEMG recorded during a standardized protocol including eight lower-limb voluntary motor tasks was analyzed using the VRI method that relates multi-muscle activation patterns of SCI persons to those of healthy-subject prototypes (n = 15). The VRI is composed of a measure of the amount of the sEMG activity (magnitude) and the distribution of activity across muscle groups compared to that of healthy subjects for each motor task (similarity index, SI). These resulting VRI components, normalized magnitude and SI, were compared to AIS clinical findings in this study. Receiver operating characteristic analysis was performed to determine the SI values best separating AIS-C and AIS-D subjects., Results: Magnitude and SI for AIS-C subjects had mean values of 0.27 +/- 0.32 and 0.65 +/- 0.21, respectively. Both parameters were significantly larger in the AIS-D subjects (0.78 +/- 0.43 and 0.93 +/- 0.06), respectively (P < 0.01). An SI value of 0.85 was found to separate AIS-C and AIS-D groups with a sensitivity of 0.89 and a specificity of 0.81. Further, the VRI of each leg strongly correlated with the respective AIS motor score (0.80, r < 0.01)., Conclusions: In the domains of voluntary motor control, the sEMG-based VRI demonstrated adequate face validity and sensitivity to injury severity as currently measured by the AIS., Sponsorship: Veterans Affairs Medical Center.

In this paper, a method for analyzing surface electromyographic (sEMG) data recorded from the lower-limb muscles of incomplete spinal-cord injured (iSCI) subjects is evaluated. sEMG was recorded bilaterally from quadriceps, adductor, hamstring, tibialis anterior, and triceps surae muscles during voluntary ankle dorsiflexion performed in the supine position as part of a comprehensive motor control assessment protocol. Analysis of the sEMG centered on two features, the magnitude of activation and the degree of similarity [similarity index (SI)] of the sEMG distribution to that of healthy subjects performing the same maneuver (n = 10). The analysis calculations resulted in response vectors (RV) that were compared to healthy-subject-derived prototype response vectors resulting in a voluntary response index (VRI). Incomplete SCI subjects (n = 9) were used to test the sensitivity of this analysis method. They were given supported-weight treadmill ambulation training, which is expected to improve or at least not cause a deterioration of voluntary motor control. The VRI provided evidence that the quantitative sEMG analysis method used was able to differentiate between healthy subjects and those with iSCI, characterize individual differences among iSCI subjects, and track motor control changes occurring over time.

Anthropogenic mercury (Hg) air emissions for the eight Great Lakes states in 1999-2000 were evaluated by analyzing three inventories. The US Environmental Protection Agency (EPA) National Emissions Inventory (NEI) had the most complete coverage for all states, and total Hg emissions ranged from 4226 lb in Minnesota to 15,828 lb in Pennsylvania. Coal-fired electric utilities accounted for 52.7% of the region's Hg emissions, varying from 20.2% of the total in New York to 67.5% in Ohio. Other important contributors to regional emissions included municipal waste combustion (5.6%), mercury-cell chlor-alkali plants and hazardous-waste incinerators (4% each), stationary internal combustion engines (ICEs) (3.5%), industrial, commercial, and institutional (ICI) boilers (3.3%), and lime manufacturing (3.0%). Although medical waste incineration accounted for just over 1% of regional emissions using the original classifications, the inclusion of health care facilities that may have been inappropriately identified with other sectors would increase the sector to 4.5% of regional emissions (and decrease the stationary ICE sector to 1.4% of the regional total). There were substantial differences for some sectors between the NEI and the Great Lakes Regional Air Toxics Emissions Inventory (GLEI), as well as unexplained differences within inventories between states (particularly for the cement, lime, and asphalt industries, and for lamp breakage). Toxics Release Inventory data for 2000 mainly covered electric utilities, and differences from the NEI were significant for several states. An independent assessment indicates the possibility of underestimated Hg emissions by about twofold for ICI boilers, although data for the sector (in particular concerning fuel oil emissions) are highly uncertain. Limited data indicate the likelihood of significant underestimates of electric arc furnace mercury emissions in the NEI and GLEI inventories. Several measures are here identified for improving the reliability of the inventories, both for modeling of atmospheric transport and deposition modeling and for tracking progress in Hg reduction initiatives.

Individuals with incomplete spinal cord injuries (SCI) retain varying degrees of voluntary motor control. The complexity of the motor control system and the nature of the recording biophysics have inhibited efforts to develop objective measures of voluntary motor control. This paper proposes the definition and use of a voluntary response index (VRI) calculated from quantitative analysis of surface electromyographic (sEMG) data recorded during defined voluntary movement as a sensitive measure of voluntary motor control in such individuals. The VRI is comprised of two numeric values, one derived from the total muscle activity recorded for the voluntary motor task (magnitude), and the other from the sEMG distribution across the recorded muscles (similarity index (SI)). Calculated as a vector, the distribution of sEMG from the test subject is compared to the average vector calculated from sEMG recordings of the same motor task from 10 neurologically intact subjects in a protocol called brain motor control assessment (BMCA). To evaluate the stability of the VRI, a group of five healthy subjects were individually compared to the prototype, average healthy-subject vectors for all of the maneuvers. To evaluate the sensitivity of this method, the VRI was obtained from two SCI subjects participating in other research studies. One was undergoing supported treadmill ambulation training, and the other a controlled withdrawal of anti-spasticity medications. The supported treadmill training patient's VRI, calculated from pre- and post-training BMCA recordings, reflected the qualitative changes in sEMG patterns and functional improvement of motor control. The VRI of the patient followed by serial BMCA during medication withdrawal also reflected changes in the motor control as a result of changes in anti-spasticity medication. To validate this index for clinical use, serial studies using larger numbers of subjects with compromised motor control should be performed.

Objectives: To compare gait during a 5-minute walk among healthy individuals, persons with spinal cord injury (SCI), and stroke survivors and to investigate whether simultaneous measures of oxygen consumption enhance information about performance., Design: Descriptive study., Setting: Veterans Affairs medical center., Participants: Thirty-nine healthy individuals, 10 persons with SCI, and 20 stroke survivors., Interventions: Participants were fitted with a portable gas analyzer and walked on a 5-m walkway for 5 minutes., Main Outcome Measures: Measures of walk distance, gait speed, gait energy expenditure (GEE), and gait cost were obtained, along with measures of ventilation (.Ve), ventilation and carbon dioxide production slope (.Ve . .VCo2), oxygen pulse, and heart rate., Results: The SCI group (127.65+/-81.74m) walked less than the stroke survivors (148.80+/-64.3m) or the healthy group (268.90+/-35.01m) but had higher energy demands, as shown by GEE (SCI group, 13.28+/-3.23mL.kg(-1).min(-1); stroke group, 10.18+/-2.14mL.kg(-1).min(-1); healthy group, 9.61+/-1.90mL.kg(-1).min(-1)) and by gait cost (SCI group,.57+/-.40 mL.kg(-1).m(-1); stroke group,.40+/-.52mL.kg(-1).m(-1); healthy group,.18+/-.02mL.kg(-1).m(-1)). Compared with the healthy group, the stroke group had higher .Ve (stroke group, 22.34+/-5.20L/min vs healthy group, 16.11+/-3.22L/min) and .Ve . .VCo2 slope (24.22+/-8.80 vs 18.73+/-5.44, respectively)., Conclusion: Use of metabolic assessment during the 5-minute walk was feasible and provided further information for evaluating gait performance with the subjects studied.

Objectives: To determine whether recent sexual intercourse might be a cause of microscopic haematuria in patients referred to a urological unit following dipstick detection of urinary haemoglobin., Subjects and Methods: Forty-eight volunteers (24 men and 24 women) consented to have heterosexual intercourse with their regular partner, and to provide samples of urine for testing before and from the first void on the morning after intercourse. After appropriate instruction, volunteers tested their own urine for the presence of blood using standard dipsticks. Any volunteer with haematuria either before or after intercourse was offered a standard haematuria assessment. The results were analysed using the chi-squared test., Results: None of the volunteers tested positively for haematuria immediately before sexual intercourse; six of the 24 women (25%), but no men, became positive after intercourse (P < 0.01). Only one of the six women accepted the offer of a haematuria evaluation and no pathology was identified., Conclusion: These results suggest that up to a quarter of women develop microscopic haematuria as a direct result of sexual intercourse. A history of recent sexual intercourse should therefore be considered when assessing the clinical significance of microscopic haematuria in women.

Objectives: To conduct a pilot study of weight-supported ambulation training after incomplete spinal cord injury (SCI), and to assess its safety., Design: Quasiexperimental, repeated measures, single group., Setting: Veterans Affairs medical center., Patients: Three subjects with incomplete, chronic, thoracic SCIs; 2 classified as D on the American Spinal Injury Association (ASIA) impairment scale and 1 as ASIA impairment scale C., Intervention: Subjects participated in 12 weeks of training assisted by 2 physical therapists. The training consisted of walking on a treadmill while supported by a harness and a pneumatic suspension device. Support started at 40% of body weight and a treadmill speed of.16kmph, and progressed by reducing support and increasing treadmill speed and continuous treadmill walking time up to 20 minutes. Training was conducted for 1 hour per day, 5 days per week for 3 months. Treadmill walking occurred for 20 minutes during the sessions., Main Outcome Measures: Gait function (speed, endurance, walking status, use of assistive device and orthotics); oxygen costs of walking; brain motor control assessment; self-report indices; ASIA classification; muscle function test; and safety., Results: All 3 subjects increased gait speed (.118m/s initially to.318m/s after training 12wk), and gait endurance (20.3m/5min initially to 63.5m/5min). The oxygen costs decreased from 1.96 to 1.33mL x kg(-1) x m(-1) after 12 weeks of training., Conclusions: This pilot study suggests that supported treadmill ambulation training can improve gait for individuals with incomplete SCIs by using objective gait measures. The self-report indices used have promise as patient-centered outcome measures of this new form of gait training. A larger, controlled study of this technique is warranted.

Photorelaxation of vascular smooth muscle (VSM) is caused by the release of nitric oxide (NO) from a finite molecular store that can be depleted by irradiating pre-contracted arteries with visible light. The ability of an 'exhausted' vessel to respond to a further period of illumination is lost temporarily but then recovers slowly as the photosensitive store is reconstituted in the dark. The recovery process, termed repriming, displays an absolute requirement for endothelium-derived NO and is inhibited by pre-treating arteries with ethacrynic acid, a thiol-alkylating agent. Here we demonstrate that agents that up- or down-regulate glutathione (GSH) biosynthesis influence the extent to which the store is regenerated in the dark. Isolated rat tail arteries (RTAs) were perfused internally with Krebs solution containing phenylephrine (PE; mean [PE] +/- s.e.mean: 5. 78+/-0.46 microM) and periodically exposed to laser light (lambda=514.5 nm, 6.3 mW cm(-2) for 6 min). Photorelaxations of control RTAs were compared with those from either (a) vessels taken from animals previously injected i.p. with buthionine sulphoximine (BSO), an inhibitor of gamma-glutamylcysteine synthetase (three injections, 100 mg kg(-1) at 8 h intervals); or (b) isolated RTAs that were perfused ex vivo with oxothiazolidine (OXO), a precursor of cysteine (10(-4) M OXO for 60 min). RTAs from BSO-treated animals exhibited attenuated photorelaxations: the mean (+/-s.e.mean) amplitude of the response recorded after 72 min recovery in the dark was 12.4+/-1.6% versus 21.4+/-2.9% for control arteries (n=5; P<0. 01). Conversely RTAs treated with OXO and allowed to recover for a similar period showed enhanced photorelaxations, 32.6+/-6.3% as compared to 21.4+/-2.9% for control arteries (n=5; P<0.01). A hyperbolic curve fit to repriming curves for BSO-treated and control arteries returned asymptote values (maximum photorelaxations) of (mean +/- s.e.mean) 24.2+/-3.2% and 55.2+/-8.5%, respectively. The level of GSH in RTA extracts was measured by high-pressure liquid chromatography (HPLC). Injecting animals with BSO decreased GSH to 85% of control levels (P<0.05) while treatment of isolated vessels with OXO resulted in a 31% increase above control levels (P<0.05). Thus, drug-induced changes in RTA GSH levels were positively correlated with altered photorelaxations. The results lead us to postulate that the photosensitive store in VSM is generated, at least in part, from intracellular GSH which becomes converted to S-nitrosoglutathione (GSNO) by nitrosating species that are formed ultimately from endothelium-derived NO. The possible physiological significance of a photolabile store of NO in VSM is discussed briefly.

Objective: To assess the factors that influence how particles might become fixed in tissues or migrate from them, by measuring the size of the injectable particles, their susceptibility to phagocytosis and their affinity for fibroblast attachment in culture., Materials and Methods: The particle size of three types of particulate unphysiological bioinjectable material, i.e. Urocol (Genesis Medical, Ltd., London), Macroplastiquetrade mark (Uroplasty Ltd., Reading, UK) and Urethrin (Mentor Medical Systems, Wantage, UK) was analysed using phase-contrast light microscopy and confocal microscopy. Human monocytes from peripheral blood were incubated with the three materials in phagocytic studies, where ingestion was determined by confocal microscopy. A fibroblast cell line was used to ascertain the ability of the particles to act as a substrate for cell attachment in culture., Results: The mean (SEM) maximum particle diameters of Macroplastique, Urethrin and Urocol were 209 (5.10) microm, 49 (1.52) microm and 14 (0.39) microm, respectively. Rat peritoneal macrophages and human peripheral blood monocytes commonly ingested Urocol particles; the phagocytosis of Urethrin was rare and that of Macroplastique was not detected. Fibroblasts adhered to Urocol paste and Urethrin particles, but not to Macroplastique., Conclusion: Published reports of particle size and phagocytosis are confusing, but a relationship clearly exists. Macroplastique is the largest particle and is least likely to be phagocytosed by human mononuclear phagocytes. Urocol paste is the slowest to dissipate in culture conditions; the flat surfaces of Urethrin, but not Macroplastique, can serve as a substrate for fibroblast anchorage.

Purpose: We prospectively studied the effect of finasteride on chronic hematuria associated with benign prostatic hyperplasia., Materials and Methods: We prospectively evaluated 57 patients with chronic intermittent hematuria who were randomized to a finasteride treated or a control arm., Results: In the untreated control group hematuria recurred in 17 patients (63%) within a year but in only 4 (14%) in the finasteride group, which was a statistically significant difference (p <0.05). Surgery was required for bleeding in 7 controls (26%), while no patient on finasteride required surgery., Conclusions: Hematuria secondary to prostatic bleeding may be significant if not treated. Finasteride appears to be effective for suppressing hematuria caused by benign prostatic hyperplasia and should be considered as treatment.

Bleeding of prostatic origin is usually caused by the friable hypervascularity of the prostate, the vessels of which are easily disrupted by physical activity. The condition is often ignored after the patient has been fully investigated and more serious causes for bleeding excluded and treatment is often withheld unless the bleeding becomes excessive. We analysed the clinical effect of finasteride in the treatment of this condition. We retrospectively reviewed 42 patients diagnosed as having haematuria secondary to bleeding from a benign prostate. Eighteen patients were simply reassured and given no treatment. Twenty-four patients with prostatic bleeding were treated using finasteride. All case notes were reviewed and the patients were contacted by telephone. Of 18 patients who had prostatic bleeding but did not receive treatment the mean age was 70 y and the mean follow-up was 10 months; two had died, nine had no further bleeding, two had a single episode of bleeding requiring no treatment, six had several bleeding episodes of whom one started finasteride, one refused treatment, and three required TURP. In the group treated with finasteride the mean follow up was 9 months, the mean age of the patients was 75 y. Twenty patients had no further bleeding, one patient experienced minor intermittent bleed and required no further treatment. Two patients died of non-urological causes, one patient stopped the treatment because of impotence and one patient had mild gynecomastia. Haematuria secondary to prostatic bleeding can be significant if not treated. Finasteride appears to be effective in suppressing haematuria caused by benign prostatic hyperplasia and should be considered in treating this problem.

Reconstruction of the bladder is a treatment available to patients who have a diseased or damaged bladder, and small bowel is the most commonly used tissue. Augmentation cystoplasty increases the total bladder capacity, whereas substitution cystoplasty replaces the whole organ. This is either drained through a continent cutaneous stoma or is reanastomosed to the urethra as an orthotopic reconstruction. Although the treatment for invasive bladder cancer has not changed greatly in the last few decades, the use of orthotopic bladder reconstruction allows for a great improvement in the quality of life for patients who undergo cystectomy. These reconstructive techniques can also be offered to patients with other forms of pelvic malignancy that involve the bladder.

Erectile impotence is more common in the diabetic than the general population, occurs at a younger age, and is often associated with ejaculatory problems. For these, and possibly for other more subtle reasons, fertility may be a problem for men with diabetes. The symptoms of erectile and ejaculatory dysfunction are frequently not discussed between patient and doctor. Psychological factors are important but the vast majority of diabetic patients have an organic basis for their impotence. Both neurogenic and vascular factors are important in the pathogenesis of erectile failure. Autonomic neuropathy is almost certainly the cause of the ejaculatory failure that may be present in up to 40% of men with diabetes. The final biochemical mediator of erection within the penile erectile tissue is nitric oxide and a key enzyme in its degradation is phosphodiesterase (type V). Drugs that affect the metabolism of this enzyme are being developed to treat erectile failure. At present, the self injection of intra-cavernosal erectogenic agents (such as prostaglandin E1) provide the main form of therapy for erectile failure. Vacuum devices are a simple alternative and venous ligation surgery may be effective for a properly selected cohort of patients. Prosthetic implants are a final option for patients in whom all else has failed. Fertility problems, particularly when associated with ejaculatory failure can be overcome with modern assisted reproductive techniques. Nowadays, these will frequently involve gamete micro-manipulation.

Objective: To develop and improve the technique of bladder replacement with ileum in patients with interstitial cystitis., Patients and Methods: A consecutive series of 27 patients (23 women and four men, median age 61 years, range 40-79) with chronic severe interstitial cystitis refractory to conservative therapies underwent cystectomy and bladder replacement using an ileal pouch. The relief of pain was assessed over a median follow-up of 30 months (range 2-48)., Results: Pain relief was complete in all patients and the median neo-bladder capacity was 520 mL (range 350-700). Only four patients required intermittent self-catheterization to drain post-micturition residual urine. Bladder calculi formed in two patients and were removed successfully at cystoscopy., Conclusion: Bladder replacement with ileum in the form of the Kock pouch is an effective surgical treatment for intractable interstitial cystitis.

Type I oculocutaneous albinism is an autosomal recessive disorder in which the biosynthesis of melanin is reduced or absent in skin, hair, and eyes because of deficient activity of tyrosinase (EC 1.14.18.1). Type I oculocutaneous albinism is caused by mutations in the tyrosinase structural gene, TYR; however, no large TYR gene deletions have been identified previously in humans. Here we report a patient with type IB oculocutaneous albinism who is a compound heterozygote for TYR allele containing a mutation that is likely to affect pre-RNA splicing and a paternally inherited allele in which the TYR gene is completely deleted, the first such allele described to date. Aside from the albinism in the proband, his phenotype and that of his normally pigmented father is otherwise normal, suggesting that this TYR deletion does not involve other functionally important contiguous genes.

Type II oculocutaneous albinism (OCA2) is an autosomal recessive disorder in which the biosynthesis of melanin pigment is reduced in the skin, hair, and eyes. OCA2, which results from mutations of the P gene, is the most frequent type of albinism in African and African-American patients. OCA2 is especially frequent in Tanzania, where it occurs with an incidence of approximately 1/1,400. We have identified abnormalities of the P gene in each of 13 unrelated patients with OCA2 from Tanzania. One of these, a deletion of exon 7, is strongly predominant, accounting for approximately 77% of mutant alleles in this group of patients.

We describe molecular prenatal diagnosis and carrier detection of tyrosinase-negative oculocutaneous albinism (OCA1A) in two families. In one family, we carried out DNA-based prenatal diagnosis of OCA1A. In the other family, mutation analysis and carrier detection obviated the need for prenatal diagnosis. Molecular analysis is safer and probably more accurate than fetoscopy and fetal scalp biopsy, and should become the method of first choice for prenatal diagnosis of OCA1.

Autosomal recessive ocular albinism (AROA) is a disorder characterized by reduced pigmentation of the retina and iris, hypoplastic fovea, variably reduced visual acuity and nystagmus. Pigmentation of the skin and hair is normal, but is usually slightly lighter than in unaffected sibs. We analysed 12 unrelated patients with AROA, and found that two had abnormalities of the tyrosinase (TYR) gene. These two patients were each a compound heterozygote for a different pathologic mutant allele and an allele containing a 'normal' polymorphism, Arg402Gln, which results in a tyrosinase polypeptide with reduced thermal stability. In these patients, AROA thus appears to represent a clinically mild form of OCA1, with a fixed visual deficit resulting from low tyrosinase activity during fetal development but with normal pigmentation of the skin and hair postnatally.

Piebaldism is an autosomal dominant genetic disorder of pigmentation characterized by white patches of skin and hair. Melanocytes are lacking in these hypopigmented regions, the result of mutations of the KIT gene, which encodes the cell surface receptor for steel factor (SLF). We describe the analysis of 26 unrelated patients with piebaldism-like hypopigmentation--17 typical patients, 5 with atypical clinical features or family histories, and 4 with other disorders that involve white spotting. We identified novel pathologic mutations or deletions of the KIT gene in 10 (59%) of the typical patients, and in 2 (40%) of the atypical patients. Overall, we have identified pathologic KIT gene mutations in 21 (75%) of 28 unrelated patients with typical piebaldism we have studied. Of the patients without apparent KIT mutations, none have apparent abnormalities of the gene encoding SLF itself (MGF), and genetic linkage analyses in two of these families are suggestive of linkage of the piebald phenotype to KIT. Thus, most patients with typical piebaldism appear to have abnormalities of the KIT gene.