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Objective To develop a measure of global functioning after moderate-severe TBI with similar measurement precision but a longer measurement range than the FIM. Design Phase 1: retrospective analysis of 5 data sets containing FIM, Disability Rating Scale, and other assessment items to identify candidate items for extending the measurement range of the FIM; Phase 2: prospective administration of 49 candidate items from phase 1, with Rasch analysis to identify a unidimensional scale with an extended range. Setting Six TBI Model System rehabilitation hospitals. Participants Individuals (N=184) with moderate-severe injury recruited during inpatient rehabilitation or at 1-year telephone follow-up. Interventions Participants were administered the 49 assessment items in person or via telephone. Main Outcome Measures Item response theory parameters: item monotonicity, infit/outfit statistics, and Factor 1 variance. Results After collapsing misordered rating categories and removing misfitting items, we derived the Brain Injury Functional Outcome Measure (BI-FOM), a 31-item assessment instrument with high reliability, greatly extended measurement range, and improved unidimensionality compared with the FIM. Conclusions The BI-FOM improves global measurement of function after moderate-severe brain injury. Its high precision, relative lack of floor and ceiling effects, and feasibility for telephone follow-up, if replicated in an independent sample, are substantial advantages.

Objective To evaluate the use of Participation Assessment with Recombined Tools–Objective (PART-O) in spinal cord injury (SCI) and compare it with the Craig Handicap Assessment and Reporting Technique–Short Form (CHART-SF). Design Follow-up survey of inception cohort. Setting Community. Participants Individuals with SCI, rehabilitated at 2 large SCI Model Systems and enrolled in the SCI Model Systems National Database, who were due for routine follow-up (N=468; median age at injury, 29; median time post injury, 5 years). Interventions Not applicable. Main Outcome Measures PART-O and CHART-SF. Results Use of Rasch analysis identified an SCI-specific scoring of PART-O that demonstrated unidimensionality (first contrast eigenvalue of 1.76) with no misfitting items or disordered steps in any response categories. Person separation and reliability were 2.00 and .80, respectively. Unlike CHART-SF, PART-O had a relatively normal distribution with no floor or ceiling effects. Test-retest reliability PART-O administered 2-4 weeks apart was 0.97, with a reliable change index of 3.1 points on a 100-point scale. PART-O correlated 0.79 with the sum of 3 CHART-SF domains with similar content. The PART-O scoring was initially validated on a second data set. Conclusions PART-O can be used successfully to measure participation in a population of people with SCI. A new method of scoring PART-O in SCI provides an initially validated, univariate interval measure of participation with good psychometric properties that has advantages over the CHART-SF legacy measure of participation.

Objective To examine the construct validity of the Participation Measure–3 Domains, 4 Dimensions (PM-3D4D), a multidimensional participation measure developed for use in rehabilitation practice. Design Cross-sectional study. Setting Outpatient rehabilitation programs. Participants Rehabilitation patients (N=556; mean age, 61.4±23.6y; 47.1% women). Interventions Not applicable. Main Outcome Measures The PM-3D4D is a 19-item measure designed to evaluate participation in 3 domains—Productivity, Social, and Community—across 4 dimensions—Diversity, Frequency, Desire for change, and Difficulty. Intercorrelations among the 4 dimensions of the PM-3D4D and correlations between the PM-3D4D and 3 legacy instruments—Participation Assessment with Recombined Tools-Objective, Participation Measure for Post-Acute Care, and Satisfaction With Life Scale—were examined to establish the convergent and divergent validity of the PM-3D4D. Known-group validity was evaluated by comparing PM-3D4D scores across age groups and groups of people classified by functional level. Results The Diversity scale of the PM-3D4D was strongly correlated with the Frequency scale (Spearman correlation coefficient, r s =.83–.96 across the 3 domains), and these 2 scales showed moderate to strong correlations with the Difficulty scale ( r s =.42–.70) but weak ( r s =−.4 to 0) and insignificant correlations with the Desire for change scale. The Frequency and Difficulty scales of the PM-3D4D showed moderate to strong correlations with the Participation Assessment with Recombined Tools-Objective and Participation Measure for Post-Acute Care ( r s =.41–.82), respectively, and the Desire for change scale had weak correlations with the Satisfaction With Life Scale ( r s =−.32 to −.18). Significant differences in PM-3D4D scores were found by age and functional level. Conclusions Findings of this study support the construct validity of the PM-3D4D, providing evidence for using the PM-3D4D to assess rehabilitation patients' participation performance and helping practitioners identify intervention priorities to improve patients' participation outcomes.

European pears (Pyrus communis L.) are stored under low temperatures to extend postharvest life. Unfortunately, senescent scald and internal breakdown are likely to occur with prolonged exposure to storage. Both disorders can be reduced by controlled atmosphere (CA) and/or the ripening inhibitor, 1-methylcylcopropene (1-MCP). The principal aim of this study was to investigate the effect of 1-MCP and CA on fruit quality, including physiological disorders, and oxidative stress metabolites in stored ‘Cold Snap’ and ‘Swiss Bartlett’ pears. Freshly harvested pears were treated with or without 1-MCP, and then stored at 0 °C under refrigerated air or CA (18 kPa or 2.5 kPa O2, and 2 kPa CO2) for at least 167 d. 1-MCP and CA delayed and/or reduced the rates of ethylene production in stored fruit of both cultivars. 1-MCP and CA delayed fruit softening and peel yellowing in ‘Swiss Bartlett’ pears, but had negligible to slight effects with ‘Cold Snap’. In both cultivars, high incidences of senescent scald and internal breakdown occurred in non-1-MCP-treated pears during refrigerated air storage. For the most part these symptoms were reduced by CA and 1-MCP, resulting in minimal to negligible incidence in 1-MCP-treated pears stored at 2.5 kPa O2. γ-Aminobutyrate accumulated in stored pears, although 1-MCP and CA slightly reduced the levels in ‘Cold Snap’ fruit and 1-MCP increased levels in ‘Swiss Bartlett’ fruit. Ascorbate (total and reduced) levels were rapidly depleted in ‘Cold Snap’ fruit, regardless of treatment; these levels were better maintained in 1-MCP-treated ‘Swiss Bartlett’ fruit than control fruit across all storage atmospheres. In both cultivars, glutathione (total and reduced) concentrations and redox status fluctuated during storage, although these levels were generally higher in 1-MCP-treated fruit. Moreover, glutathione depletion occurred in advance of the development of senescence disorders in stored pear fruit.

Objective To compare patient functional outcomes across Traumatic Brain Injury Model Systems (TBIMS) rehabilitation centers using an enhanced statistical model and to determine factors that influence those outcomes. Design Multicenter observational cohort study. Setting TBIMS centers. Participants Patients with traumatic brain injury (TBI) admitted to 19 TBIMS rehabilitation centers from 2003–2012 (N=5505). Interventions Not applicable. Main Outcome Measures Functional outcomes of patients with TBI. Results Individuals with lower functional status at the time of admission, longer duration of posttraumatic amnesia, and higher burden of medical comorbidities continued to have worse functional outcomes at discharge from inpatient rehabilitation and at the 1-year follow-up, whereas those who were employed at the time of injury had better outcomes at both time periods. Risk-adjusted patient functional outcomes for patients in most TBIMS centers were consistent with previous research. However, there were wide performance differences for a few centers even after using more recently collected data, improving on the regression models by adding predictors known to influence functional outcomes, and using bootstrapping to eliminate confounds. Conclusions Specific patient, injury, and clinical factors are associated with differences in functional outcomes within and across TBIMS rehabilitation centers. However, these factors did not explain all the variance in patient outcomes, suggesting a role of some other predictors that remain unknown.

Controlled atmosphere (CA) storage limits ethylene-related ripening of apple fruit, but can promote the development of CA-related injury. CA-related injury can be exacerbated by the ethylene antagonist, 1-methylcyclopropene (1-MCP). The main objective of this study was to investigate the impact of pre-storage conditioning, 1-MCP and elevated CO2 on the development of CA-related injury and oxidative stress metabolites in ‘Honeycrisp’ (Malus × domestica Borkh.) apple fruit. Upon harvest, fruit were treated with or without 1 μL L−1 1-MCP for 24 h, and then transferred to CA (2.5 kPa O2 and 2.5 kPa or 0.03 kPa CO2) at 3 °C (no conditioning) or conditioned at 10 °C for 5 d prior to CA. Apples were CA-stored for up to 35 weeks. CA-related injury occurred with storage under both CA regimes, regardless of 1-MCP and conditioning, whereas 1-MCP exacerbated the negative impact of elevated CO2 on this disorder, approximating an 80% incidence, which was coincident with a 400% increase in γ-aminobutyrate (GABA). By comparison, pre-storage conditioning reduced the negative impact of 1-MCP on the incidence of CA-related injury at 2.5 kPa CO2 by nearly 80%, and this was associated with a dramatically lower GABA concentration. Overall, rapid declines in total ascorbate and ascorbate/dehydroascorbate ratios were evident with storage, regardless of treatment. Transient declines in total glutathione and glutathione/glutathione disulphide ratios were more rapid and sustained for longer periods of time in conditioned than non-conditioned fruit. There were dramatic shifts in the levels of phosphorylated and non-phosphorylated pyridine dinucleotides with storage duration, regardless of treatment, resulting in elevated ratios of NADPH/NADP+ and NADH/NAD+ after 35 weeks, especially for conditioned fruit subjected to elevated CO2. Canonical powered partial least squares analysis revealed that metabolite profiles changed with storage period and treatment, and were most divergent during elevated CO2 storage. Moreover, CA-related injury was strongly associated with changes in GABA, and moderately linked to total glutathione and glutathione redox status.

Objective To examine resilience at 3 months after traumatic brain injury (TBI). Design Cross-sectional analysis of an ongoing observational cohort. Setting Five inpatient rehabilitation centers, with 3-month follow-up conducted primarily by telephone. Participants Persons with TBI (N=160) enrolled in the resilience module of the TBI Model System study with 3-month follow-up completed. Interventions Not applicable. Main Outcome Measure Connor-Davidson Resilience Scale. Results Resilience scores were lower than those of the general population. A multivariable regression model, adjusting for other predictors, showed that higher education, absence of preinjury substance abuse, and less anxiety at follow-up were significantly related to greater resilience. Conclusions Analysis suggests that lack of resilience may be an issue for some individuals after moderate to severe TBI. Identifying persons most likely at risk for low resilience may be useful in planning clinical interventions.

In combination with low temperature, controlled atmosphere storage and 1-methylcyclopropene (ethylene antagonist) application are used to delay senescence of many fruits and vegetables. Controlled atmosphere consists of low O2 and elevated CO2. When sub-optimal partial pressures are used, these practices represent multiple abiotic stresses that can promote the development of physiological disorders in pome fruit, including flesh browning and cavities, although there is some evidence for genetic differences in susceptibility. In the absence of surface disorders, fruit with flesh injuries are not easily distinguished from asymptomatic fruit until these are consumed. Oxidative stress metabolites tend to accumulate (e.g., γ-aminobutyrate) or rapidly decline (e.g., ascorbate and glutathione) in vegetative tissues exposed to hypoxic and/or elevated CO2 environments. Moreover, these phenomena can be associated with altered energy and redox status. Biochemical investigations of Arabidopsis and tomato plants with genetically-altered levels of enzymes associated with the γ-aminobutyrate shunt and the ascorbate-glutathione pathway indicate that these metabolic processes are functionally related and critical for dampening the oxidative burst in vegetative and fruit tissues, respectively. Here, we hypothesize that γ-aminobutyrate accumulation, as well energy and antioxidant depletion are associated with the development of physiological injury in pome fruit under multiple environmental stresses. An improved understanding of this relationship could assist in maintaining the quality of stored fruit.

Objective To evaluate the psychometric properties and validity of an expanded set of community enfranchisement items that are suitable for computer adaptive testing. Design Survey. Setting Community setting. Participants Individuals with disabilities (N=1163) were recruited from an online panel generation company (51%), former rehabilitation inpatients (18%), disability community organizations (13%), a registry of rehabilitation patients (10%), and Traumatic Brain Injury and Spinal Cord Injury Model System facilities (8%). Inclusion criteria were a self-identified disability, aged ≥18 years, and the ability to read and speak English. Interventions None. Main Outcome Measure Community enfranchisement. Results Exploratory and confirmatory factor analyses of the 48 enfranchisement items suggested 2 distinct subsets of items: (1) importance of participation and (2) control over participation. Principal components analysis of the residuals suggested that the 2 item sets are unidimensional. Rating scale analysis provided evidence that the 2 item sets fit the Rasch model. Importance and control were moderately correlated with each other and with disability severity. Conclusions Importance of participation and control over participation define 2 distinct sets of participation enfranchisement. Preliminary evidence supports their validity.

Objectives To describe the application of practice-based evidence (PBE) methodology to spinal cord injury (SCI) rehabilitation in the SCIRehab study, and to summarize associations of patient characteristics and treatment interventions to outcomes. Design Prospective observational study. Setting Six SCI rehabilitation centers. Participants Patients with traumatic SCI (N=1376) admitted for first rehabilitation. Interventions Not applicable. Main Outcome Measures FIM and residence at discharge, and FIM, residence, Craig Handicap Assessment and Reporting Technique, work/school status, Patient Health Questionnaire-9, Diener Satisfaction with Life Scale, rehospitalization, and presence of pressure ulcers at 1 year postinjury. Results Patient demographic and injury characteristics explained significant variation in rehabilitation outcomes, particularly functional outcomes. Regression modeling also identified a large number of significant associations with outcomes when total time in each discipline was modeled and when models were developed for each discipline, examining time spent in the many specific interventions provided by each discipline. Conclusions The application of PBE methodology in the SCIRehab study provided extensive information about the process of inpatient SCI rehabilitation. While patient demographic and injury characteristics explain substantial variation in rehabilitation outcomes, particularly functional outcomes, significant relations also were found between the type and quantity of treatment interventions delivered by each rehabilitation discipline and a broad range of outcomes.

γ-Aminobutyrate (GABA) accumulates in apple fruit during controlled atmosphere storage. Here, we demonstrated that GABA levels declined markedly in apples ( Malus × domestica Borkh. cv. Empire) within 3 h after transfer from controlled atmosphere storage (3 °C, 2.5 kPa O 2 , 2.5 kPa CO 2 ) to ambient conditions. Also, we identified two genes encoding apple fruit GABA transaminase (GABA-T), the enzyme responsible for the catabolism of GABA to succinic semialdehyde. The deduced amino acid sequences of the two Md GABA-T enzymes were 93% identical to each other, and 74–83% identical to known Arabidopsis and tomato GABA-Ts. Transient expression of the individual full-length proteins fused to the green fluorescent protein in tobacco suspension-cultured cells revealed that Md GABA-T1 and Md GABA-T2 were localized to mitochondria. Removal of the N-terminal targeting presequences yielded good recovery of the soluble recombinant proteins in Escherichia coli when they were co-expressed with the GroES/EL molecular chaperone complex. Continuous monitoring of recombinant GABA-T activity via a bacterial NADP + -dependent succinic semialdehyde dehydrogenase-linked assay established that the two GABA-Ts in apple fruit, like the mitochondrial GABA-T in Arabidopsis and the mitochondrial, plastidial and cytosolic GABA-Ts in tomato, utilized pyruvate and glyoxylate, but not 2-oxoglutarate. Thus, the substrate specificity of the two apple fruit GABA-Ts was similar to that for the GABA-Ts in Arabidopsis and tomato. However, the existence of two GABA-Ts in the mitochondria of apple fruit differed from the scenarios found in the other two species, providing yet another variation on the subcellular distribution of GABA-Ts in plant cells.

Jette AM, Tulsky DS, Ni P, Kisala PA, Slavin MD, Dijkers MP, Heinemann AW, Tate DG, Whiteneck G, Charlifue S, Houlihan B, Williams S, Kirshblum S, Dyson-Hudson T, Zanca J, Fyffe D. Development and initial evaluation of the Spinal Cord Injury-Functional Index. Objectives To describe the calibration of the Spinal Cord Injury-Functional Index (SCI-FI) and report on the initial psychometric evaluation of the SCI-FI scales in each content domain. Design Cross-sectional survey followed by calibration data simulations. Setting Inpatient and community settings. Participants A sample of participants (N=855) with traumatic spinal cord injury (SCI) recruited from 6 SCI Model Systems and stratified by diagnosis, severity, and time since injury. Interventions None. Main Outcome Measure SCI-FI instrument. Results Item response theory analyses confirmed the unidimensionality of 5 SCI-FI scales: basic mobility (54 items), fine motor function (36 items), self-care (90 items), ambulation (39 items), and wheelchair mobility (56 items). All SCI-FI scales revealed strong psychometric properties. High correlations of scores on simulated computer adaptive testing (CAT) with the overall SCI-FI domain scores indicated excellent potential for CAT to accurately characterize functional profiles of adults with SCI. Overall, there was very little loss of measurement reliability or precision using CAT compared with the full item bank; however, there was some loss of reliability and precision at the lower and upper ranges of each scale, corresponding to regions where there were few questions in the item banks. Conclusions Initial evaluation revealed that the SCI-FI achieved considerable breadth of coverage in each content domain and demonstrated acceptable psychometric properties. The use of CAT to administer the SCI-FI will minimize assessment burden, while allowing for the comprehensive assessment of the functional abilities of adults with SCI.

4-Aminobutyrate (GABA) accumulates in various plant parts, including bulky fruits such as apples, in response to abiotic stress. It is generally believed that the GABA is derived from glutamate, although a contribution from polyamines is possible. Putrescine, but not spermidine and spermine, generally accumulates in response to the genetic manipulation of polyamine biosynthetic enzymes and abiotic stress. However, the GABA levels in stressed plants are influenced by processes other than putrescine availability. It is hypothesized that the catabolism of putrescine to GABA is regulated by a combination of gene-dependent and -independent processes. The expression of several putative diamine oxidase genes is weak, but highly stress-inducible in certain tissues of Arabidopsis. In contrast, candidate genes that encode 4-aminobutyraldehyde dehydrogenase are highly constitutive, but not stress inducible. Changes in O(2) availability and cellular redox balance due to stress may directly influence the activities of diamine oxidase and 4-aminobutyraldehyde dehydrogenase, thereby restricting GABA formation. Apple fruit is known to accumulate GABA under controlled atmosphere storage and therefore could serve as a model system for investigating the relative contribution of putrescine and glutamate to GABA production.

Bogner JA, Whiteneck GG, Corrigan JD, Lai J-S, Dijkers MP, Heinemann AW. Comparison of scoring methods for the Participation Assessment with Recombined Tools–Objective. Objective To develop and compare 2 scoring algorithms for a measure of participation, the Participation Assessment with Recombined Tools–Objective (PART-O) based on the assumption that more participation is better versus an alternative that reflects balance in domains of participation. Design Survey. Setting Community settings. Participants Three groups of participants under the age of 65 years were included: (1) persons with spinal cord injury, traumatic brain injury, stroke, and other disorders who are commonly treated in acute rehabilitation settings (n=220), and (2) participants from the general population who did (n=366) or (3) did not (n=284) self-report limitations indicative of a disability who participated in the 2006 Colorado Behavioral Risk Factor Surveillance System (N=870). Interventions Not applicable. Main Outcome Measure PART-O. Results We developed PART-O subscores using a consensus process and then evaluated them empirically. We combined subscores using 2 contrasting algorithms, one using average scores and the other reflecting the amount of participation and variation in participation across 3 domains. The algorithms for the total scores yielded normal distributions in all 3 samples and were equally sensitive to the impact of disability. While strongly correlated, about 30% of the variance of the 2 total scores was not shared. Conclusions Two scoring algorithms for the PART-O illustrate contrasting perspectives of the construct of participation. The 2 algorithms may be used in future studies to expand our understanding of the construct of participation.

Heinemann AW, Lai J-S, Magasi S, Hammel J, Corrigan JD, Bogner JA, Whiteneck GG. Measuring participation enfranchisement. Objective To reflect the perspectives of rehabilitation stakeholders in a measure of participation enfranchisement that can be used by people with and without disabilities. Design Survey. Setting Community settings. Participants We pilot-tested a draft instrument with 326 adults who had sustained stroke, spinal cord injury, traumatic brain injury, or other disabling condition, as well as a general population sample. We administered a revised version of the instrument to a statewide sample drawn from the 2006 Colorado Behavioral Risk Factors Surveillance System that included persons with (N=461) and without (N=451) self-identified activity limitations. Interventions None. Main Outcome Measure Participation enfranchisement. Results We used multidimensional scaling, exploratory factor analysis (EFA) and confirmatory factor analysis (CFA), followed by rating scale analysis to evaluate the psychometric properties of the instrument. EFA identified 3 participation enfranchisement factors that describe perceived choice and control, contributing to one's community, and feeling valued; the factors were supported marginally by CFA. Rating scale analysis revealed marginal person separation and no misfitting items. Conclusions Participation enfranchisement constitutes a new, previously unmeasured aspect of participation—one that addresses subjective perceptions rather than objective performance—with items that are clearly distinct from more generalized satisfaction with participation. The 19 enfranchisement items describe aspects of participation that may prove useful in characterizing longer-term rehabilitation outcomes.

Whiteneck GG, Gassaway J, Dijkers MP, Lammertse DP, Hammond F, Heinemann AW, Backus D, Charlifue S, Ballard PH, Zanca JM. Inpatient and postdischarge rehabilitation services provided in the first year after spinal cord injury: findings from the SCIRehab study. Objective To examine the amount and type of therapy services received in inpatient and postdischarge settings during the first year after spinal cord injury (SCI). Design Prospective observational longitudinal cohort design. Data were obtained from systematic recording of interventions by clinicians and from patient interview. Setting Inpatient and postdischarge rehabilitation programs. Participants Patients (N=493) with traumatic SCI admitted to 6 rehabilitation centers participating in the SCIRehab study. Interventions Not applicable. Main Outcome Measures Hours of therapy by physical therapy (PT), occupational therapy (OT), speech therapy, recreation therapy, psychology, social work/case management, and nursing education during initial inpatient rehabilitation and postdischarge up to the first anniversary of injury. Inpatient data were collected prospectively by the treating clinicians; postdischarge service data were collected by patient self-report during follow-up interviews. Results Of the total hours spent on these rehabilitation interventions during the first year after injury, 44% occurred after discharge from inpatient rehabilitation. Participants received 56% of their PT hours after discharge and 52% of their OT hours, but only a minority received any postdischarge services from other rehabilitation disciplines. While wide variation was found in the total hours of inpatient treatment across all disciplines, the variation in the total hours of postdischarge services was greater, with the interquartile range of postdischarge services being twice that of the inpatient services. Conclusions SCI rehabilitation is often given in a care continuum, with inpatient rehabilitation being only the beginning. Reductions in inpatient SCI rehabilitation length of stay are well documented, but the postdischarge services that may replace some inpatient treatment appear to be greater than previously reported. The availability and impact of postdischarge care should be studied in greater detail to capture the wide array of postdischarge services and outcomes.

Introduction/Background Participation is a key concept in the International Classification of Functioning, Disability, and Health and a central rehabilitation outcome, but agreement on measuring participation is lacking. Participation Assessed with Recombined Tools–Objective (PART-O) was developed for traumatic brain injury (TBI), used in the TBI Model Systems, and endorsed as a common data element. However, the content of PART-O is not unique to TBI and the instrument may be applicable to other populations. The aim of this research is to determine the psychometric properties of PART-O in people with spinal cord injury (SCI). Material and method The PART-O items were administered to 468 people with SCI from 4 months to 40 years post injury along with the most frequently used measure of participation in SCI: the Craig Handicap Assessment and Reporting Technique (CHART). The PART-O was administered a second time, 2–4 weeks later to assess test-retest reliability. Rasch analysis was used to ensure a unidimensional linear measure and evaluate the psychometric properties of PART-O in SCI. Results To achieve unidimensionality and maintain ordered steps within item categories, 3 competing items (hours per week spent working, in school, and homemaking) were summed into a testlet, and infrequently endorsed categories were combined. The resulting measure was unidimensional (first contrast less than 2.00) with all items fitting well (no infit or outfit above 1.40 and no disordered categories in any item), and acceptable person separation (2.00) and reliability (0.80). PART-O had a normal distribution with no ceiling or floor effects. The test-retest reliability was 0.97 and the correlation between PART-O and CHART was 0.79. Conclusion The PART-O shows promise for expanding its use into SCI. It is highly correlated with the legacy CHART instrument, and it has advantages over CHART, of being a normally distributed linear measure without ceiling effects.

Plants produce p-aminobenzoate (pABA) in chloroplasts and use it for folate synthesis in mitochondria. In plant tissues, however, pABA is known to occur predominantly as its glucose ester (pABA-Glc), and the role of this metabolite in folate synthesis has not been defined. In this study, the UDP-glucose:pABA acyl-glucosyltransferase (pAGT) activity in Arabidopsis extracts was found to reside principally (95%) in one isoform with an apparent Km for pABA of 0.12 mm. Screening of recombinant Arabidopsis UDP-glycosyltransferases identified only three that recognized pABA. One of these (UGT75B1) exhibited a far higher kcat/Km value than the others and a far lower apparent Km for pABA (0.12 mm), suggesting its identity with the principal enzyme in vivo. Supporting this possibility, ablation of UGT75B1 reduced extractable pAGT activity by 95%, in vivo [14C]pABA glucosylation by 77%, and the endogenous pABA-Glc/pABA ratio by 9-fold. The Keq for the pABA esterification reaction was found to be 3 × 10-3. Taken with literature data on the cytosolic location of pAGT activity and on cytosolic UDP-glucose/UDP ratios, this Keq value allowed estimation that only 4% of cytosolic pABA is esterified. That pABA-Glc predominates in planta therefore implies that it is sequestered away from the cytosol and, consistent with this possibility, vacuoles isolated from [14C]pABA-fed pea leaves were estimated to contain≥88% of the [14C]pABA-Glc formed. In total, these data and the fact that isolated mitochondria did not take up [3H]pABA-Glc, suggest that the glucose ester represents a storage form of pABA that does not contribute directly to folate synthesis.

Folates break down in vivo to give pterin and p-aminobenzoylglutamate (pABAGlu) fragments, the latter usually having a polyglutamyl tail. Pilot studies have shown that plants can hydrolyze pABAGlu and its polyglutamates to p-aminobenzoate, a folate biosynthesis precursor. The enzymatic basis of this hydrolysis was further investigated. pABAGlu hydrolase activity was found in all species and organs tested; activity levels implied that the proteins responsible are very rare. The activity was located in cytosol/vacuole and mitochondrial fractions of pea (Pisum sativum L.) leaves, and column chromatography of the activity from Arabidopsis tissues indicated at least three peaks. A major activity peak from Arabidopsis roots was purified 86-fold by a three-column procedure; activity loss during purification exceeded 95%. Size exclusion chromatography gave a molecular mass of approximately 200 kDa. Partially purified preparations showed a pH optimum near 7.5, a Km value for pABAGlu of 370 microM, and activity against folic acid. Activity was relatively insensitive to thiol and serine reagents, but was strongly inhibited by 8-hydroxyquinoline-5-sulfonic acid and stimulated by Mn2+, pointing to a metalloenzyme. The Arabidopsis genome was searched for proteins similar to Pseudomonas carboxypeptidase G, which contains zinc and is the only enzyme yet confirmed to attack pABAGlu. The sole significant matches were auxin conjugate hydrolase family members and the At4g17830 protein. None was found to have significant pABAGlu hydrolase activity, suggesting that this activity resides in hitherto unrecognized enzymes. The finding that Arabidopsis has folate-hydrolyzing activity points to an enzymatic component of folate degradation in plants.

Whiteneck G, Meade MA, Dijkers M, Tate DG, Bushnik T, Forchheimer MB. Environmental factors and their role in participation and life satisfaction after spinal cord injury. Arch Phys Med Rehabil 2004;85:1793-803. Objectives: To investigate environmental barriers reported by people with spinal cord injury (SCI), and to determine the relative impact of environmental barriers compared with de- mographic and injury characteristics and activity limitations in predicting variation in participation and life satisfaction. Design: Cross-sectional, follow-up survey. Setting: Individuals rehabilitated at 16 federally designated Model Spinal Cord Injury Systems of care, now living in the community. Participants: People with SCI (N2726) who completed routine follow-up research interviews between 2000 and 2002. Interventions: Not applicable. Main Outcome Measures: The Craig Hospital Inventory of Environmental Factors-Short Form (CHIEF-SF), the Craig Handicap Assessment and Reporting Technique-Short Form, and the Satisfaction With Life Scale. Results: The top 5 environmental barriers reported by sub- jects with SCI, in descending order of importance, were the natural environment, transportation, need for help in the home, availability of health care, and governmental policies. The CHIEF-SF subscales accounted for only 4% or less of the variation in participation; they accounted for 10% of the vari- ation in life satisfaction. Conclusions: The inclusion of environmental factors in models of disability was supported, but were found to be more strongly related to life satisfaction than to societal participa

Objective To develop and test a new instrument to assess environmental barriers encountered by people with and without disabilities by using a questionnaire format. Design New instrument development. Setting A rehabilitation hospital and community. Participants Two convenience samples: (1) 97 subjects, 50 with disabilities and 47 without disability, and (2) 409 subjects with disabilities from spinal cord injury, traumatic brain injury, multiple sclerosis, amputation, or auditory or visual impairments. In addition, a population-based sample in Colorado of 2269 people (mean age, 44y; 57% men) with and without disabilities. Interventions Not applicable. Main outcome measures Item development; factor structure; test-retest, subject-proxy and internal consistency reliability; content, construct, and discriminant validity; and subscale and abbreviated version development. Results Panels of experts on disability developed items for the Craig Hospital Inventory of Environmental Factors (CHIEF). The instrument measured the frequency and magnitude of environmental barriers reported by individuals. Five subscales were derived from factor analysis measuring (1) attitudes and support, (2) services and assistance, (3) physical and structural, (4) policy, and (5) work and school environmental barriers. The CHIEF total score had high test-retest reliability (intraclass correlation coefficient [ICC]=.93) and high internal consistency (Cronbach α=.93), but lower participant-proxy agreement (ICC=.62). Significant differences were found in CHIEF scores among groups of people with known differences in disability levels and disability categories. Conclusions The CHIEF has good test-retest and internal consistency reliability with evidence of content, construct, and discriminant validity resulting from its development strategy and psychometric assessments in samples of the general population and among people with a variety of disabilities.

Whiteneck G, Brooks CA, Mellick D, Harrison-Felix C, Terrill MS, Noble K. Population-based estimates of outcomes after hospitalized for traumatic brain injury in Colorado. Arch Phys Med Rehabil 2004;85(4 Suppl 2):S73–81. Objective To determine statewide, population-based outcomes of persons hospitalized with traumatic brain injury (TBI) at 1 year postinjury. Design Follow-up survey of a representative cohort. Setting A statewide, population-based registry and follow-up system for persons hospitalized with TBI. Participants A total of 1591 adult Coloradoans with moderate and severe injury oversampled, but weighted to be representative of persons hospitalized with TBI (1996–1999) who survived their injuries and completed follow-up telephone interviews at 1 year postinjury. Interventions Not applicable. Main outcome measures Checklists of symptoms and service utilization, the FIM instrument™, the Craig Handicap Assessment and Reporting Technique Short Form, a single-item quality of life (QOL) measure, and a needs assessment checklist. Results Problematic outcomes occurring at 1 year postinjury included one third or more being bothered by fatigue, feeling irritable or grouchy, having headaches, and experiencing trouble sleeping more frequently than preinjury; 37% reported needing the assistance of another person in physical and/or cognitive activities of daily living; substantial participation restrictions were noted in areas of occupation (30%) and social integration (22%); and 29% responded that their QOL was only fair or poor. Negative outcomes were reported more frequently among individuals who were more severely injured, older, or female. Conclusions Substantial percentages of people hospitalized with TBI in a population-based sample reported a variety of problematic outcomes at 1 year postinjury.

Corrigan JD, Harrison-Felix C, Bogner J, Dijkers M, Terrill MS, Whiteneck G. Systematic bias in traumatic brain injury outcome studies because of loss to follow-up. 2003;84:153-60. Objective: To identify potential sources of selection bias created by subjects lost to follow-up in studies of traumatic brain injury (TBI). Design: Demographic, premorbid, injury-related, and hospital course characteristics were compared for subjects lost and found for 1- and 2-year postinjury follow-ups by using bivariate tests and logistic regression analysis. Setting: Three prospective, longitudinal data sets[mdash ]a single center, a multicenter, and a statewide incidence surveillance system and follow-up registry. Participants: Adolescents and adults hospitalized with a diagnosis of TBI. Interventions: Not applicable. Main Outcome Measures: Subjects were considered lost when no information was collected from the person with TBI or only limited information could be obtained from a proxy, for any reason, including death, refusal, inability to locate, and inability to interview. Results: At year 1 follow-up, 58.0% to 58.6% of subjects were found; 39.7% to 42.0% of subjects were found by year 2. Variables most frequently associated with loss to follow-up were cause of injury, blood alcohol level, motor function, hospital payer source, and race and ethnicity. Conclusions: TBI follow-up studies may experience selective attrition of subjects who (1) are socioeconomically disadvantaged, (2) have a history of substance abuse, and (3) have violent injury etiologies. These phenomena are mitigated for those with more severe motor deficits. Loss to follow-up may be a problem inherent to this population; however, the high rate and its selective nature are problematic for outcome studies. [copy ] 2003 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation

Groah SL, Weitzenkamp DA, Lammertse DP, Whiteneck GG, Lezotte DC, Hamman RF. Excess risk of bladder cancer in spinal cord injury: evidence for an association between indwelling catheter use and bladder cancer. Arch Phys Med Rehabil 2002;83:346-51. Objectives: To evaluate whether the risk of bladder cancer is greater in individuals with spinal cord injury (SCI) than in the general population and whether indwelling catheter (IDC) use is a significant independent risk factor for bladder cancer. Design: Historical cohort study in which subjects with SCI were stratified according to bladder management method and followed for the development of bladder cancer. Setting: A large rehabilitation hospital in the Spinal Cord Injury Model Systems. Participants: A total of 3670 patients with SCI who were evaluated for bladder cancer on at least 1 occasion by cystoscopy over a period of 1 to 47 years. Interventions: Not applicable. Main Outcome Measures: Bladder cancer occurring after SCI determined by diagnosis at our facility, by subject report, or by report of next of kin. Results: Twenty-one cases of bladder cancer were found in the 3670 study participants. The risk of bladder cancer for subjects with SCI using IDC is 77 per 100,000 person-years, corresponding to an age- and gender-adjusted standardized morbidity ratio (SMR) of 25.4 (95% confidence interval [CI], 14.0–41.9) when compared with the general population. After controlling for age at injury, gender, level and completeness of SCI, history of bladder calculi, and smoking, those using solely IDC had a significantly greater risk of bladder cancer (relative risk [RR] = 4.9; 95% CI, 1.3–13.8) than those using nonindwelling methods. Mortality caused by bladder cancer in individuals with SCI was significantly greater than that of the US population (SMR = 70.6; 95% CI, 36.9–123.3). Conclusions: Bladder cancer risk and mortality are heightened in SCI compared with the general population. IDC is a significant independent risk factor for the increased risk of and mortality caused by bladder cancer in the SCI population. © 2002 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation

Cusick CP, Brooks CA, Whiteneck GG. The use of proxies in community integration research. Arch Phys Med Rehabil 2001;82:1018-24. Objective: To assess the level of agreement between persons with various disabilities and their proxies in reporting community integration outcomes using the Craig Handicap Assessment and Reporting Technique (CHART). Design: Reliability study. Setting: Participants living in the community for a minimum of 6 months after onset of disability or completion of inpatient rehabilitation. Participants: Persons (n = 983) with disability resulting from amputation, burn, multiple sclerosis, spinal cord injury (SCI), stroke, or traumatic brain injury and their self-selected proxies. Interventions: Telephone interview of subjects (FIM™ instrument, CHART); proxies (CHART). FIM instrument assesses the degree of assistance with physical and cognitive subscales; CHART measures community integration in 6 subscales: physical, cognitive, and economic independence, and mobility, social integration, and occupation. Main Outcome Measures: Intraclass correlation coefficients (ICCs) were used to assess participant-proxy agreement, and stepwise multiple regressions were used to identify patterns of difference in agreement based on disability type and demographic variables. Results: Thirty-seven of the 38 items examined for the entire sample yielded moderate to strong ICCs. Multiple regression analyses indicated that proxies overrated participants with severe functional cognitive disabilities on the mobility subscale (p

Krause JS, Coker JL, Charlifue S, Whiteneck GG. Health outcomes among American Indians with spinal cord injury. Arch Phys Med Rehabil 2000;81:924-31. Objective: To identify factors related to risk for poor health outcomes and secondary conditions in a sample of American Indians with spinal cord injury (SCI). Design: Interviews were conducted by telephone with most participants; those who did not have telephones returned materials by mail. Setting: A large rehabilitation hospital in the Western/Mountain region of the United States. Participants: Ninety-seven American Indians with SCI completed a comprehensive health interview. All participants were adults with traumatic SCI and were at least 1 year postinjury. Main Outcome Measures: Selected items from the Behavioral Risk Factor Surveillance System were used to assess health behaviors and general health outcomes. Two secondary conditions were also investigated as outcome measures: pressure sores and post-SCI injuries. Results: Multiple linear regression was used to predict seven health-related outcomes. Depressive symptomatology and post-SCI injuries were the primary predictors of the majority of health outcomes. Alcohol consumption was associated with a greater risk for post-SCI injuries, and being older at injury was associated with poorer health outcomes. Conclusions: Interventions to reduce depression, injuries, and alcohol misuse have potential for improving health among American Indians with SCI. © 2000 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation

Cutter NC, Scott DD, Johnson JC, Whiteneck G. Gabapentin effect on spasticity in multiple sclerosis: a placebo-controlled, randomized trial. Arch Phys Med Rehabil 2000;81:164-9. Objective: To investigate the effect of gabapentin on subject self-report and physician-administered spasticity scales in individuals with multiple sclerosis. Design: Prospective, double-masked, placebo-controlled, crossover design. Setting: The Multiple Sclerosis Center at the Denver Veterans Affairs Medical Center. Intervention: Subjects were titrated to either 900mg gabapentin orally three times a day or placebo over a 6-day period. Subjects underwent a 14-day washout and then were crossed over. No other changes were made to their medication regimen. Main Outcome Measures: The outcome measures were divided into two categories: subject self-report scales physician-administered scales. Subject self-report scales included the spasm frequency scale, spasm severity scale, interference with function scale, painful spasm scale, and global assessment scale. Physician-administered scales included the Modified Ashworth Scale, clonus scale, deep tendon reflexes, plantar stimulation response, and the Kurtzke Expanded Disability Status (EDSS) Scale. Digit Span and Digit Symbol subtests of the WAIS-R Intelligence Scale were administered to assess for possible impaired concentration. The Fatigue Impact Scale was administered to assess for changes in fatigue. The adjective generation technique was administered to assess for alterations in mood. Results: A statistically significant reduction in the impairment of spasticity was found in the gabapentin-treated subjects compared with placebo as measured by the self-report scales of the spasm severity scale, interference with function scale, painful spasm scale, and global assessment scale and by the physician-administered scales of the Modified Ashworth and plantar stimulation response. No significant difference was noted in the Digit Span, Digit Symbol, adjective generation technique, and EDSS. Conclusion: Gabapentin reduces the impairment of spasticity, compared with placebo, without the side effects of worsening concentration and fatigue. © 2000 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation

Objective: To identify patterns of health behaviors and health outcomes among a sample of American Indian men with spinal cord injury. Design: Telephone interviews with all participants, except those who did not have telephones (they returned materials by mail). Setting: Large rehabilitation hospital in the Western mountain region of the United States. Participants: Seventy-six American Indian men with traumatic SCI of at least 1 year in duration. Main Outcome Measure: Selected health-related behaviors from the Behavioral Risk Factor Surveillance System (BRFSS) were used to assess health behaviors and general health outcomes among the American Indian SCI sample and to compare findings with those from American Indian men without SCI based on nationwide BRFSS data. Results: The study participants reported lower overall health and satisfaction with health care than the non-SCI BRFSS group. They also reported a different pattern of health behaviors, including a greater frequency of inoculations for flu and pneumonia but a lower rate of HIV testing and cholesterol screening. A smaller percentage of American Indians used alcohol, but those who did reported more heavy drinking. Conclusions: American Indians with SCI are more likely to receive health care consistent with the prevention of secondary conditions of SCI (eg, pneumonia), but less likely to receive basic health screens intended to prevent chronic health diseases.