Differences in activities of daily living (ADL) abilities of children across world regions: a validity study of the assessment of motor and process skills

BACKGROUND

One important goal of paediatric occupational therapy services is to improve activities of daily living (ADL) abilities of children. In order to plan and evaluate the effectiveness of targeted interventions, valid assessments are critically needed. The Assessment of Motor and Process Skills (AMPS) is an internationally standardized assessment of ADL performance that has not been validated for use with children in Middle Europe.

AIM

To evaluate for (i) significant differences in mean ADL motor and mean ADL process ability measures among children from Middle Europe compared with children from North America, UK/Republic of Ireland, Nordic countries, Western Europe, Australia/New Zealand and Asia; and (ii) meaningful differences between the international age-normative means of the AMPS and those for children from Middle Europe.

METHOD

We analysed data of children across world regions extracted from the international AMPS database using many-facet Rasch and two-way anova analyses and by estimating contrasts to evaluate for significant group differences.

RESULTS

anova analyses of data for 11 189 children ages 2-15 revealed significant effects for mean ADL motor and ADL process ability by region [F ≥ 15.32, d.f. = (6, 11 091), MSE ≥ 0.20, P < 0.001, ή(2) ≥ 0.008], and age [F ≥ 253.47, d.f. = (13, 11 091), MSE ≥ 0.20, P < 0.001, ή(2) ≥ 0.229], and a significant interaction effect for mean ADL process ability [F = 1.48, d.f. = (78, 11 091), P = 0.004, ή(2) = 0.010]. Out of 168 estimated contrasts between Middle Europe and the other world regions for mean ADL motor and ADL process ability, seven were statistically significant (4.17%), but none exceeded ±1SE from the international means.

CONCLUSION

The AMPS remains free of relevant differences in mean ADL ability measures between Middle Europe and other world regions, indicating that the international age-normative mean values are likely to be applicable to children from Middle Europe. The AMPS can be used internationally to evaluate ADL performance in children and to determine if the child is eligible for occupational therapy services.

Familial Aggregation of Morbid Obesity

Recent studies have shown major gene effects for obesity in randomly ascertained families. To investigate the familial aggregation of a specific subset of obesity, which is particularly prone to medical complications, families with morbid obesity were studied. This condition occurs in 1%-2% of the population and is defined as 45.5 kg (100 pounds) or more over ideal weight. First-degree relatives of 221 morbidly obese probands (1560 adults) were identified, and height and weight (current and greatest) were obtained from each family member. Morbid obesity occurred in the family members of the probands 8 times more often than in the general population. Of the morbidly obese probands, 48% had one or more first-degree relatives who were also morbidly obese compared to a 6% population estimate. By the ages of 20-24, 12% of the morbidly obese probands were already 45.5 kg or more overweight, and 45% were 22.7 kg (50 pounds) or more overweight. There was little difference in the prevalence of familial morbid obesity by the gender of the probands: 47% of the male probands and 48% of the female probands had another morbidly obese relative, while 67% and 53% of the early onset (before age 25) male and female probands, respectively, had one or more first-degree relatives who were also morbidly obese. In addition to the extreme degree of familial aggregation, the prevalence of morbid obesity in parent-offspring sets was calculated within the morbidly obese families. Morbidly obese families who have one or two morbidly obese parents have a 2.6 times increased risk (p<0.002) of having one or more morbidly obese adult offspring, compared to families who have neither parent morbidly obese. Evidence for trimodality of the body mass index distribution was found for each gender (p = 0.0006 for male relatives and p = 0.075 for female relatives). The strong familial aggregation of morbid obesity indicates the need for further understanding of the genetic determinants of this extreme clinical disorder and how environmental factors affect the genetic expression of the trait.

Activities of daily living performance in dementia

OBJECTIVE

To explore the activities of daily living ADL performance profile of community-living people with dementia and to investigate its relationship with dementia severity.

MATERIALS & METHODS

ADL performance of 86 subjects were evaluated using Barthel Index (BI), Lawton and Brody's Instrumental Activities Daily Living (IADL) and Assessment of Motor and Process Skills (AMPS). Dementia severity was measured by Clinical Dementia Rating (CDR).

RESULTS

Subjects were able to perform most basic ADL (BI mean = 16.4) and some IADL (Lawton and Brody's IADL mean = 4.3). The AMPS process ability measure and the Lawton and Brody's IADL were significantly correlated with CDR (P < 0.01).

CONCLUSIONS

Subjects with mild dementia were able to perform mostly all basic ADL and some IADL. The AMPS process ability measure and the Lawton and Brody's IADL could provide useful information on their ability to live independently in the community.

Aerobic exercise in water versus walking on land: effects on indices of fat reduction and weight loss of obese women

AIM

It has been suggested, that water exercise is less effective than weight-bearing exercise on land for body fat reduction.

METHODS

To test this hypothesis 38 middle-aged obese women (25-47% body fat) participated in a 13 week exercise-diet program to compare the effects of aerobic exercise in water versus walking on land on indices of fat reduction and weight loss changes. Subjects were randomly assigned to 1 of 3 exercise groups: 1) walking on land (WL), 2) swimming (SW) at 27 degrees C water temperature and 3) walking in 29 degrees C water (WW) at the shallow end of a declining pool with the water at navel height. Subjects in the SW group alternated breast-, side-, and backstroke swimming without face immersion. Exercise parameters were kept constant for all three groups. Subjects participated in supervised exercise sessions for 40 min, 4 times a week at 70% of age-predicted maximum heart rate. Subjects were tested before and after the 13-week experimental period.

RESULTS

Significant reductions in body weight, (5.9 kg), percent body fat, (3.7%), and skinfold and girth measurements, occurred in all groups. There where no significant differences between groups.

CONCLUSIONS

The results of this study indicate that there are no differences in the effect of aerobic activities in the water versus weight-bearing aerobic exercise on land on body composition components as long as similar intensity, duration and frequency are used.

Validity of a performance assessment of activities of daily living for people with developmental disabilities

BACKGROUND

Since clients with different types of developmental disabilities often experience difficulties in activities of daily living (ADL), it is critical that assessments of ADL are evaluated in order to ensure that one can make valid judgements based on the results of the appraisal. The purpose of the present study was to evaluate the validity of a specific performance assessment instrument, the Assessment of Motor and Process Skills (AMPS), when used by occupational therapists with clients with developmental disabilities. Unlike global ADL assessments, the AMPS is used not only to evaluate the level of ADL dependence, but also to estimate the quality of each specific action performed when a person is performing ADL tasks.

METHODS

Data were gathered from 1724 participants with different developmental disabilities, including intellectual disability (ID), cerebral palsy and spina bifida. Many-Facet Rasch (MFR) analysis was used to examine person-response validity, and task and item scale validity.

RESULTS

Goodness-of-fit statistics showed that the tasks and items had acceptable scale validity. The participants had acceptable person-response validity on the ADL motor scale, but had slightly lower than expected levels of person-response validity on the ADL process scale. The results indicate that clients with more severe forms of ID may have a higher proportion of different performance profiles in ADL than is expected by the MFR model of the AMPS. Since the proportion of participants who did not meet the criteria was only 3% lower than expected and in accordance with other studies, the difference may not be clinically meaningful. Otherwise, the results indicated that the AMPS is a valid tool when used with clients with developmental disabilities.

CONCLUSIONS

Further research is needed to evaluate the use of the AMPS in clinical assessment and intervention planning for this group of clients.

The alternate forms reliability of the new tasks added to the Assessment of Motor and Process Skills

The purpose of this study was to evaluate the alternate forms reliability of new tasks vs. old tasks of the Assessment of Motor and Process Skills (AMPS). The participants in this study were 44 persons taken from the AMPS database who had completed two old tasks and two new tasks within a 4-day period. Paired t tests revealed no significant difference between the means of ADL ability measures based on the performance of new vs. old tasks. The Pearson product moment correlations between the ADL ability measures based on the performance of new vs. old tasks was r =.92, p <.001 for motor ability measures and r =.77, p <.001 for process ability measures. We found that 100% of the ADL motor ability measures had standardized differences less than 2.00 (p <.05) and 97% of the ADL process ability measures had standardized differences less than 2.00 (p <.05). Considered together, the results support good alternate forms reliability of the ADL motor and ADL process ability measures. This study supported the finding that the 20 newly calibrated IADL and PADL tasks can be used reliably in clinical practice. When the AMPS is used to evaluate change, we can have 80 to 93% confidence that paired ability measures that change by more than +0.5 logits are the result of actual changes in ability.

Sensory adaptation in naive peripheral CD4 T cells

T cell receptor interactions with peptide/major histocompatibility complex (pMHC) ligands control the selection of T cells in the thymus as well as their homeostasis in peripheral lymphoid organs. Here we show that pMHC contact modulates the expression of CD5 by naive CD4 T cells in a process that requires the continued expression of p56(lck). Reduced CD5 levels in T cells deprived of pMHC contact are predictive of elevated Ca(2)+ responses to subsequent TCR engagement by anti-CD3 or nominal antigen. Adaptation to peripheral pMHC contact may be important for regulating naive CD4 T cell responsiveness.

Stroke volume does not plateau during graded exercise in elite male distance runners

Stroke volume (SV) responses during graded treadmill exercise were studied in 1) elite male distance runners (N = 5), 2) male university distance runners (N = 10), and 3) male untrained university students (N = 10).

METHODS

Cardiac output (Q) and SV were determined by a modified acetylene rebreathing procedure.

RESULTS

There were no differences in SV responses among the three groups during the transition from rest to light exercise (P > 0.05). However, the rates of change of SV during light to maximal exercise in untrained subjects (slope = -0.1544 mL x beat(-1)) and university distance runners (slope = 0.1041) did not change, whereas it dramatically increased (P < 0.001) in elite distant runners (slope = 0.6734). Moreover, the elite distance runners showed a further slope increase in SV when heart rate was above 160 bpm, which resulted in an average maximal SV of 187 +/- 14 mL x beat(-1) compared with 145 +/- 8 and 128 +/- 14 mL x beat(-1) in the university runners and untrained students, respectively (P < 0.001). Similarly, max Q reached 33.8 +/- 2.3, 26.3 +/- 1.7, and 21.3 +/- 1.5 L x min(-1) in the three groups, respectively (P < 0.001). On the other hand, there was a nonsignificant tendency for maximal arteriovenous oxygen content difference to be lower in the elite athletes compared with the other groups.

CONCLUSION

Results from university distance runners and untrained university students support the classic observation that SV plateaus at about 40% of maximal oxygen consumption despite increasing intensity of exercise. In contrast, stroke volume in the elite athletes does not plateau but increases continuously with increasing intensity of exercise over the full range of the incremental exercise test.

Validity of using the Assessment of Motor and Process Skills to estimate overall home safety in persons with psychiatric conditions

OBJECTIVE

Occupational therapists often base estimates of home safety on their behavioral observations of a client performing functional activities during a hospitalization. To examine this practice, this study investigated the predictive validity of the Assessment of Motor and Process Skills (AMPS) to the overall home safety of persons with psychiatric conditions associated with cognitive impairments.

METHOD

Ability in activities of daily living (ADL) of 20 participants was evaluated with the AMPS before discharge from an inpatient psychiatric unit. Within approximately 2 weeks of their discharge, the participants' home safety was evaluated within their home settings using the Safety Assessment of Function and the Environment for Rehabilitation. To form a basis for comparison, a second administration of the AMPS was administered concurrently with the home safety evaluation.

RESULTS

Moderate positive relationships were found between ADL motor and ADL process ability and home safety in both the clinic and the home; however, analyses of the sensitivity, specificity, and overall predictive values revealed that home ADL process ability was the best predictor of home safety for participants who were categorized as less safe in the study.

CONCLUSION

Findings suggest that clinic ADL evaluations using the AMPS give a reasonable estimate of home safety for participants categorized as having more home safety risk. For participants categorized as having less home safety risk, clinic ADL evaluation using the AMPS produced significantly less accurate estimates than ADL evaluations conducted in the home. These results indicate that home safety estimates may be most accurate if they are based on home rather than clinic ADL process ability measures.

Nonequivalent nuclear location of immunoglobulin alleles in B lymphocytes

Individual B lymphocytes normally express immunoglobulin (Ig) proteins derived from single Ig heavy chain (H) and light chain (L) alleles. Allelic exclusion ensures monoallelic expression of Ig genes by each B cell to maintain single receptor specificity. Here we provide evidence that at later stages of B cell development, additional mechanisms may contribute to prioritizing expression of single IgH and IgL alleles. Fluorescent in situ hybridization analysis of primary splenic B cells isolated from normal and genetically manipulated mice showed that endogenous IgH, kappa and lambda alleles localized to different subnuclear environments after activation and had differential expression patterns. However, this differential recruitment and expression of Ig alleles was not typically seen among transformed B cell lines. These data raise the possibility that epigenetic factors help maintain the monoallelic expression of Ig.

The validity of adding new tasks to the assessment of motor and process skills

OBJECTIVE

Twenty-one new activities of daily living (ADL) tasks were evaluated for the validity of their inclusion into the Assessment of Motor and Process Skills (AMPS).

METHOD

Data from 1,484 participants who performed at least one new AMPS task were analyzed to determine whether the new tasks (a) fit the AMPS many-faceted Rasch (MFR) model and (b) increase the range of the AMPS motor and process skill scales.

RESULTS

Twenty of the 21 new tasks fit the MFR model. The AMPS motor scale was increased by .25 logit at the easier end of the scale and by .30 logit at the more difficult end of the scale. The AMPS process scale was increased by .14 logit at the easier end of the scale. The more difficult end of the AMPS process scale did not increase.

CONCLUSION

These findings support the validity of adding 20 new tasks into the AMPS. The new tasks provide the following benefits for testing clients whose ADL ability levels are at the lower or higher ends of the AMPS motor or process skill scales: (a) potential for less error when estimating the ADL ability measures, (b) more task choices, and (c) more face-valid tasks for testing men.

Evolutionary conservation, developmental expression, and genomic mapping of mammalian Twisted gastrulation

The twisted gastrulation gene (tsg) encodes a secreted protein required for the correct specification of dorsal midline cell fate during gastrulation in Drosophila. We report that tsg homologs from human, mouse, zebrafish, and Xenopus share 72-98% identity at the amino acid level and retain all 24 cysteine residues from Drosophila. In contrast to Drosophila where tsg expression is limited to early embryos, expression is found throughout mouse and human development. In Drosophila, tsg acts in synergy with decapentaplegic (dpp), a member of the TGF-beta family of secreted proteins. The vertebrate orthologs of dpp, BMP-2 and -4, are crucial for gastrulation and neural induction, and aberrant signaling by BMPs and other TGF-beta family members results in developmental defects including holoprosencephaly (HPE). Interestingly, human TSG maps to the HPE4 locus on Chromosome 18p11.3, and our analysis places the gene within 5 Mbp of TG-interacting factor (TGIF).

Expression of alpha- and beta-globin genes occurs within different nuclear domains in haemopoietic cells

The alpha- and beta-globin gene clusters have been extensively studied. Regulation of these genes ensures that proteins derived from both loci are produced in balanced amounts, and that expression is tissue-restricted and specific to developmental stages. Here we compare the subnuclear location of the endogenous alpha- and beta-globin loci in primary human cells in which the genes are either actively expressed or silent. In erythroblasts, the alpha- and beta-globin genes are localized in areas of the nucleus that are discrete from alpha-satellite-rich constitutive heterochromatin. However, in cycling lymphocytes, which do not express globin genes, the distribution of alpha- and beta-globin genes was markedly different. beta-globin loci, in common with several inactive genes studied here (human c-fms and SOX-1) and previously (mouse lambda5, CD4, CD8alpha, RAGs, TdT and Sox-1), were associated with pericentric heterochromatin in a high proportion of cycling lymphocytes. In contrast, alpha-globin genes were not associated with centromeric heterochromatin in the nucleus of normal human lymphocytes, in lymphocytes from patients with alpha-thalassaemia lacking the regulatory HS-40 element or entire upstream region of the alpha-globin locus, or in mouse erythroblasts and lymphocytes derived from human alpha-globin transgenic mice. These data show that the normal regulated expression of alpha- and beta-globin gene clusters occurs in different nuclear environments in primary haemopoietic cells.

Naturalistic assessment of functional performance in school settings: reliability and validity of the School AMPS scales

The School Assessment of Motor and Process Skills (School AMPS) is an assessment tool designed to be used by occupational therapists to measure the effectiveness of a student's ability to perform school tasks in naturalistic classroom settings. Rater reliability, internal scale validity, and person response validity of the School AMPS was investigated by examining the goodness-of-fit of raters, motor and process skill items, and students to the many-faceted Rasch model used in the development of the School AMPS. Five of six raters demonstrated acceptable goodness-of-fit (MnSq < or = 1.4 and z < 2). All 36 motor and process skill items demonstrated acceptable goodness-of-fit. Of the 208 students in the study, 93.7% demonstrated acceptable goodness-of-fit on the School AMPS motor scale and 88.9% demonstrated acceptable goodness-of-fit on the School AMPS process scale. The results of this study support the rater reliability, scale validity, and person response validity for the School AMPS as a tool to be used to evaluate the effectiveness of student performance of school tasks in the classroom setting.

An assessment of various household food security measures in Hawaiì has implications for national food security research and monitoring

The Core Food Security Module (CFSM), the national food security monitoring tool, requires three affirmative responses to categorize households as food insecure. If this tool is unreliable or inaccurate, vulnerable segments of our population may be adversely affected. The objectives of the present study were to assess the credibility of applying the CFSM categorical measure to a population sample from Hawaiì and to assess the concurrent validity of the CFSM, the new face-valid measure and measures adapted from the Radimer/Cornell (RC) measure and Community Childhood Hunger Identification Project. The sample included 1469 respondents gathered through a statewide telephone sample and 144 food pantry recipients. Responses to the 18 CFSM questions were used to create all four measures. The credibility of the CFSM categorical measure was also assessed via comparisons with individual items and with the 1995 national modal CFSM response pattern. Categorical measures were compared across food security prevalence estimates and indices of income and vegetable intake and with the CFSM scale measure. Differences in the modal response pattern between samples affected CFSM categorization. Only 36% of households followed the Hawaiì modal response pattern, and categorization was not consistent with the content of key items. Although 85% of the households were classified as food secure by the CFSM, only 78% were classified as food secure with each of the other food security measures. Concurrent validity of all measures was confirmed. A reassessment of the national CFSM categorical measure appears warranted.

Training to improve awareness of disabilities in clients with unilateral neglect

OBJECTIVE

Awareness of disabilities is known to be a central problem of rehabilitation among clients with large right cerebrovascular lesions and unilateral neglect. The aim of this study was to evaluate the effect of an intervention program focused on improving the awareness of disabilities in four participants with unilateral neglect. The intervention program developed for this study was based on the assumption that awareness of disabilities is a prerequisite for being able to learn and use compensatory techniques in the performance of activities of daily living (ADL).

METHOD

The study followed a single-case experimental ABA design. The Assessment of Awareness of Disability was used to measure awareness of disabilities; the Assessment of Motor and Process Skills was used to measure ADL ability; and neuropsychological tests were used to assess unilateral neglect and sustained attention. The intervention program used meaningful and purposeful occupations as therapeutic change agents to improve awareness of disabilities.

RESULTS

Awareness of disabilities and ADL ability improved in all four participants; unilateral neglect decreased in three participants; and sustained attention improved in two participants.

CONCLUSION

The preliminary findings indicate that training to improve awareness of disabilities might improve the ability to learn the use of compensatory techniques in the performance of ADL in clients with unilateral neglect. The effects of the intervention strategy need to be evaluated further in future research.

ADL performance of black Americans and white Americans on the assessment of motor and process skills

OBJECTIVE

The purpose of this study was to examine whether the Assessment of Motor and Process Skills (AMPS), an assessment of personal and domestic activities of daily living (ADL) performance, can be used as a valid, nonbiased tool when assessing black Americans.

METHOD

The participants were 466 blacks and 466 whites drawn from the entire sample of blacks and whites contained in the AMPS database who met the following criteria: (a) were 16 years of age and older; (b) had a notable history of a neurological, musculoskeletal, medical, developmental, cognitive, or psychiatric disorders or were healthy older persons; and (c) resided in North America. The participants were matched according to functional level, gender, diagnosis, and age. Examination for bias included between-group comparison of (a) item difficulty and task challenge hierarchies of the AMPS, (b) goodness-of-fit of the participants to the many-faceted Rasch (MFR) model, and (c) mean ADL motor and ADL process abilities.

RESULTS

Both the item difficulty and the task challenge hierarchies remained stable between the two groups. On the ADL Motor scale, 95.3% of the black participants and 92.4% of the white participants demonstrated acceptable goodness-of-fit (MS < or = 1.4, z < 2) to the MFR model. On the ADL Process scale, 91.2% of the black participants and 90.1% of the white participants demonstrated acceptable goodness-of-fit. A significant difference, t(2, 930) = 3.56, p < .01, between the two groups was found in mean ADL process ability, but no significant difference, t(2, 930) = .69, p = .49) was found in mean ADL motor ability.

CONCLUSION

The results of this study support the validity of the AMPS when applied to black Americans.

The core food security module scale measure is valid and reliable when used with Asians and Pacific Islanders

The Core Food Security Measure (CFSM) is used nationally to assess the extent and severity of household food insecurity in the previous 12 mo due to inadequate money for food. Both a scale measure and a categorical measure were developed from a national cross-sectional sample. The objective of this research was to determine whether the CFSM scale measure is a reliable and valid food security measure for use in Hawaii, where at least 50% of the population is of Asian or Pacific Islander descent. We completed an independent assessment of the robustness of the internal scale construct validity of the CSFM scale measure and hierarchical order of items using the same Rasch methods used previously to develop the CSFM. From a sample of 1664 respondents, data from 362 were used in the Rasch analysis. Item goodness-of-fit statistics indicated that responses to the "adults cut the size or skip meals" item and its follow-up item were redundant [outfit mean-square residual (MnSq) = 0.6, z = -2]. Responses to the "(un)able to eat balanced meals" item were erratic (outfit MnSq = 2.1, z = 2). Findings pertaining to goodness-of-fit of the respondents indicated an acceptable rate of misfit (4.7%). Rate of misfit did not vary with family status or with any ethnic group except the Samoans. Overall, the CFSM scale measure fit as well with the Hawaii data as it did with national data, although identified limitations may affect food security monitoring and research.

Targeting of Ikaros to pericentromeric heterochromatin by direct DNA binding

Ikaros is a sequence-specific DNA-binding protein that is essential for lymphocyte development. Little is known about the molecular function of Ikaros, although recent results have led to the hypothesis that it recruits genes destined for heritable inactivation to foci containing pericentromeric heterochromatin. To gain further insight into the functions of Ikaros, we have examined the mechanism by which it is targeted to centromeric foci. Efficient targeting of Ikaros was observed upon ectopic expression in 3T3 fibroblasts, demonstrating that lymphocyte-specific proteins and a lymphoid nuclear architecture are not required. Pericentromeric targeting did not result from an interaction with the Mi-2 remodeling factor, as only a small percentage of Mi-2 localized to centromeric foci in 3T3 cells. Rather, targeting was dependent on the amino-terminal DNA-binding zinc finger domain and carboxy-terminal dimerization domain of Ikaros. The carboxy-terminal domain was required only for homodimerization, as targeting was restored when this domain was replaced with a leucine zipper. Surprisingly, a detailed substitution mutant analysis of the amino-terminal domain revealed a close correlation between DNA-binding and pericentromeric targeting. These results show that DNA binding is essential for the pericentromeric localization of Ikaros, perhaps consistent with the presence of Ikaros binding sites within centromeric DNA repeats. Models for the function of Ikaros that are consistent with this targeting mechanism are discussed.

Different doses of agonistic ligand drive the maturation of functional CD4 and CD8 T cells from immature precursors

MHC molecules are normally required for the development of thymocytes from the CD4(+)CD8(+) double-positive to the CD4 or CD8 single-positive stage. Here we show that mitogenic plant lectins can substitute for MHC molecules in driving the differentiation of phenotypically and functionally mature CD4 as well as CD8 T cells. Interestingly, lectin dosage determines whether CD4 or CD8 cells are generated, indicating that variation of cumulative signal strength (not necessarily signal quality) can result in an apparent switching of lineage preference. Thymocyte perception of differentiation-inducing signals is modulated by the cellular context, since stimuli that yield CD8 cells in the context of the thymic microenvironment fail to do so in suspension culture and generate CD4 progeny instead. Finally, we show that lectin-generated single-positive thymocytes retain the ability to respond to the ligands initially used to drive their differentiation. Our results call into question generalizations and predictions made from other experimental systems and reveal that thymocyte selection is considerably more flexible than had been anticipated.

Intrathymic deletion of MHC class I-restricted cytotoxic T cell precursors by constitutive cross-presentation of exogenous antigen

Cross-priming of cytotoxic T lymphocytes by professional antigen-presenting cells (APC) is a potential hazard to self tolerance because it exposes naive T cells to tissue-specific self antigens in the context of co-stimulatory signals. Here we show that cross-presentation of exogenous material occurs constitutively within the thymus. Although efficient cross-presentation is a property of relatively few APC it results in thymocyte deletion both in vitro and in vivo, suggesting that intrathymic cross-presentation can operate as an effective component of tolerance to circulating self antigens. The capacity of minor cell populations to mediate thymocyte deletion but not positive selection reflects an underlying difference in the biology of these two processes.

Alternate forms reliability of the assessment of motor and process skills

The purpose of this study is to examine the alternate forms reliability of the AMPS (Assessment of Motor and Process Skills) (Fisher, 1997a) where alternate forms means different pairs of AMPS tasks. The participants for this study were persons selected from the AMPS database who had performed four AMPS tasks. The participants varied in age, gender, diagnosis, and level of assistance needed to live in the community. The AMPS was administered by trained and calibrated occupational therapists according to standardized procedures. The data for the 91 participants were subjected to 12 many-faceted Rasch analyses to generate ADL motor and ADL process ability measures for each task and each set of paired tasks. Repeated measures ANOVAs revealed no time effect across the four AMPS tasks. Pearson product moment correlations between Tasks 1 and 2 combined and Tasks 3 and 4 combined were r = .91 and r = .86 for the ADL motor and ADL process scales, respectively. Calculation of the standardized difference (z) revealed that no more than 8% of the participants had ADL motor or ADL process ability measures that differed significantly between observations once we accounted for real differences in a persons performance; 80% of the paired ADL motor and ADL process ability measures remained stable within +/- 0.5 logits when the participants performed two tasks. The AMPS ADL motor and ADL process scales can be used reliably in clinical practice and for research purposes.

Dynamic repositioning of genes in the nucleus of lymphocytes preparing for cell division

We show that several transcriptionally inactive genes localize to centromeric heterochromatin in the nucleus of cycling but not quiescent (noncycling) primary B lymphocytes. In quiescent cells, centromeric repositioning of inactive loci was induced after mitogenic stimulation. A dynamic repositioning of selected genes was also observed in developing T cells. Rag and TdT loci were shown to relocate to centromeric domains following heritable gene silencing in primary CD4+8+ thymocytes, but not in a phenotypically similar cell line in which silencing occurred but was not heritable. Collectively, these data indicate that the spatial organization of genes in cycling and noncycling lymphocytes is different and that locus repositioning may be a feature of heritable gene silencing.

The dimensionality and validity of the Older Americans Resources and Services (OARS) Activities of Daily Living (ADL) Scale

The psychometric properties of the OARS ADL scale, comprised of seven physical activities of daily living (PADL) and seven instrumental activities of daily living (IADL) items, were examined using a Rasch measurement approach. Two of the PADL items failed to demonstrate acceptable goodness-of-fit with the measurement model but the remaining 12 items could be combined into a single measure of ADL ability. Although the OARS ADL scale was designed to identify those community-dwelling elderly who need supports and services to continue to live in the community, the scale items were found to be poorly targeted to community-dwelling elderly since almost half of our sample received maximal scores. Rasch analysis identified how we might improve the sensitivity of the OARS ADL scale but its utility in outcome and longitudinal studies remains questionable.

Uniting practice and theory in an occupational framework. 1998 Eleanor Clarke Slagle Lecture

The term occupation conveys the powerful essence of our profession--enabling people to seize, take possession of, or occupy the spaces, time, and roles of their lives. Occupation is activity that is both purposeful and meaningful to the person who engages in it. Our uniqueness lies in our use of occupation as a therapeutic agent, but our unique focus on occupation is not always apparent in practice. Four global groups of activities that occupational therapy practitioners use in practice are described--exercise, contrived occupation, therapeutic occupation, and adaptive occupation. Therapeutic occupation and adaptive occupation are proposed as the legitimate activities of occupational therapy. The Occupational Therapy Intervention Process Model is then presented. This model stresses a top-down approach to evaluation and provides a framework for implementing adaptive occupation for purposes of compensation as well as therapeutic occupation for purposes of remediation.

Environment effect of functional task performance in adults with acquired brain injuries: use of the assessment of motor and process skills

OBJECTIVE

To examine household task performance in both familiar (home) and unfamiliar (clinic) environments in adults with acquired brain injuries.

DESIGN

The research performed was a comparison study examining the effect of the environment on functional task performance. Individuals were evaluated using the Assessment of Motor and Process Skills both in their homes and in an unfamiliar clinic setting.

PARTICIPANTS

Twenty individuals with acquired brain injuries living in the community.

MAIN OUTCOME MEASURES

The Assessment of Motor and Process Skills, an observational, standardized, occupational therapy assessment tool, was used to evaluate household task performance.

RESULTS

Paired one-tailed t tests indicated a significant difference between home and clinic performance measures in process ability (t=-4.28, p=.00), but no significant difference in motor ability performance measures (t=-1.84, p=.410). Scatter plot analyses showed that performance scores of 6 of the 20 subjects differed in a clinically meaningful way, and that instrumental activities of daily living motor performance scores for 3 of the 20 differed in a clinically meaningful way.

CONCLUSIONS

Individuals with acquired brain injuries may be influenced by their environment when performing household tasks, although further study is necessary to determine the extent of the environmental effect.

Helios, a T cell-restricted Ikaros family member that quantitatively associates with Ikaros at centromeric heterochromatin

The Ikaros gene encodes multiple protein isoforms that contribute critical functions during the development of lymphocytes and other hematopoietic cell types. The intracellular functions of Ikaros are not known, although recent studies have shown that Ikaros proteins colocalize with inactive genes and centromeric heterochromatin. In this study, Ikaros proteins were found to be components of highly stable complexes. The complexes from an immature T cell line were purified, revealing associated proteins of 70 and 30 kD. The p70 gene, named Helios, encodes two protein isoforms with zinc finger domains exhibiting considerable homology to those within Ikaros proteins. Helios and Ikaros recognize similar DNA sequences and, when overexpressed, Helios associates indiscriminately with the various Ikaros isoforms. Although Ikaros is present in most hematopoietic cells, Helios was found primarily in T cells. The relevance of the Ikaros-Helios interaction in T cells is supported by the quantitative association of Helios with a fraction of the Ikaros. Interestingly, the Ikaros-Helios complexes localize to the centromeric regions of T cell nuclei, similar to the Ikaros localization previously observed in B cells. Unlike the B cell results, however, only a fraction of the Ikaros, presumably the fraction associated with Helios, exhibited centromeric localization in T cells. These results establish immunoaffinity chromatography as a useful method for identifying Ikaros partners and suggest that Helios is a limiting regulatory subunit for Ikaros within centromeric heterochromatin.

Association of transcriptionally silent genes with Ikaros complexes at centromeric heterochromatin

Ikaros proteins are required for normal T, B, and NK cell development and are postulated to activate lymphocyte-specific gene expression. Here we examined Ikaros distribution in the nucleus of B lymphocytes using confocal microscopy and a novel immunofluorescence in situ hybridization (immuno-FISH) approach. Unexpectedly, Ikaros localized to discrete heterochromatin-containing foci in interphase nuclei, which comprise clusters of centromeric DNA as defined by gamma-satellite sequences and the abundance of heterochromatin protein-1 (HP-1). Using locus-specific probes for CD2, CD4, CD8alpha, CD19, CD45, and lambda5 genes, we show that transcriptionally inactive but not transcriptionally active genes associate with Ikaros-heterochromatin foci. These findings support a model of organization of the nucleus in which repressed genes are selectively recruited into centromeric domains.

How many thymocytes audition for selection?

T cell maturation requires the rearrangement of clonotypic T cell receptors (TCR) capable of interacting with major histocompatibility complex (MHC) ligands to initiate positive and negative selection. Only 3-5% of thymocytes mature to join the peripheral T cell pool. To investigate the basis for this low success rate, we have measured the frequency of preselection thymocytes capable of responding to MHC. As many as one in five MHC-naive thymocytes show upregulation of activation markers on exposure to MHC-expressing thymic stroma in short-term reaggregate culture. The majority of these cells display physiological changes consistent with entry into the selection process within 24 h. By exposing TCR transgenic thymocytes to a range of MHC-peptide complexes, we show that CD69 induction is indicative of thymocyte selection, positive or negative. Our data provide evidence that the fraction of thymocytes that qualify to enter the thymic selection process far exceeds the fraction that successfully complete it, and suggest that most MHC-reactive thymocytes are actively eliminated in the course of selection.

Rational primer design greatly improves differential display-PCR (DD-PCR)

Since its conception in 1992, differential display PCR (DD-PCR) has attracted widespread interest. Theoretically an attractive cloning approach, it combines the comparative analysis of several samples with the sensitivity of PCR. Although a large number of studies embracing this technology have been initiated, few novel genes of interest have been identified, suggesting that the method has not realised its potential. The present report shows that by modifying primer design, sampling of differentially expressed genes can be greatly enhanced and relevant genes can be isolated. Using our modified conditions DD-PCR efficiently screens a wide range of gene expression levels, in which differences are represented on a linear scale.

Effects of familiarity of task and choice on the functional performance of younger and older adults

An experiment was conducted to compare the functional performance of younger and older adults on familiar and unfamiliar tasks under 2 conditions of perceived control. Specifically, the relation between age and motor and process skills was examined. The familiar tasks were simple cooking tasks, whereas the unfamiliar tasks were contrived, meaningless tasks developed for this study. Younger and older adults did not differ in the ratings of the familiarity of the tasks, but results from 2 Age x Task x Choice analyses of variance demonstrated a significant age difference for motor and process skills under all conditions. This suggests that older adults demonstrate age-related decline, even with activities that take motivational, experiential, and ecological validity components into account. For the process skills scale, there was also a significant main effect for choice. These results support the concept that perceived control may improve performance, but not differentially for older adults; that is, younger and older adults both demonstrated improved process performance when given their choice of tasks.

Effects of familiarity of task and choice on the functional performance of younger and older adults

An experiment was conducted to compare the functional performance of younger and older adults on familiar and unfamiliar tasks under 2 conditions of perceived control. Specifically, the relation between age and motor and process skills was examined. The familiar tasks were simple cooking tasks, whereas the unfamiliar tasks were contrived, meaningless tasks developed for this study. Younger and older adults did not differ in the ratings of the familiarity of the tasks, but results from 2 Age x Task x Choice analyses of variance demonstrated a significant age difference for motor and process skills under all conditions. This suggests that older adults demonstrate age-related decline, even with activities that take motivational, experiential, and ecological validity components into account. For the process skills scale, there was also a significant main effect for choice. These results support the concept that perceived control may improve performance, but not differentially for older adults; that is, younger and older adults both demonstrated improved process performance when given their choice of tasks.

Measuring functional competence in older persons with Alzheimer's disease

Despite their limitations, mental status tests and self/proxy reports of instrumental activities of daily living (IADL) are often used to predict functional competence. In contrast, the Assessment of Motor and Process Skills (AMPS) is a direct observational assessment of IADL competence. Sixty-four community-dwelling elderly (20 Alzheimer's disease [AD] patients and 44 nondemented) were assessed with the AMPS, the Mini-Mental State Examination (MMSE), and the Older Americans Resources and Services (OARS)-IADL. Performance on all three assessments was significantly lower for the AD sample. The MMSE did not correlate significantly with the AMPS motor ability measures but it correlated modestly with the AMPS process ability measures. The OARS-IADL correlated significantly with the AMPS motor ability measure for the nondemented sample alone. Although mental status and self/proxy assessments provide some insight into individuals' IADL competence, direct observation of IADL task performance provides additional information regarding the subtle process and motor skills changes that occur in progressive dementing conditions.

The assessment of motor and process skills applied cross-culturally to the Japanese

OBJECTIVES

The purposes of this study were to examine the cross-cultural validity of the Assessment of Motor and Process Skills (AMPS) as well as the reliability of raters from different cultures.

METHOD

Six trained raters from diverse cultural backgrounds scored 10 Japanese subjects' performances on familiar and culturally relevant tasks of their own choosing.

RESULTS

Results indicated high cross-cultural validity and interrater reliability for the AMPS, as indicated by goodness of fit of subjects and raters via the many-faceted Rasch measurement model. The relative rater severity was also evaluated cross-culturally by the standardized difference (z). The Japanese rater and one of the three American raters varied significantly in severity between their scoring of Japanese subjects versus European subjects.

CONCLUSION

The results support the hypothesis that the AMPS can be used as a cross cultural instrumental activities of daily living assessment. Further study is needed to clarify the issue of possible cultural bias in rater severity.

Male and female performance on the assessment of motor and process skills

OBJECTIVE

To examine the validity of the assertion that men and women do not differ significantly on the Assessment of Motor and Process Skills (AMPS), a functional assessment tool used to evaluate the interaction between component motor and process skills and IADL (instrumental or domestic activities of daily living) performance capacity.

DESIGN

Descriptive comparison. Using many-faceted Rasch analysis, the AMPS motor and process scales were examined for differential item response between gender subgroups. Mean motor and process ability measures of age-matched groups of male and female subjects were also compared.

PARTICIPANTS

A convenience sample of more than 3,500 men and women from the standardization sample for the pilot version of the AMPS computer-scoring software. The subjects had a variety of physical disabilities or psychiatric diagnoses.

MAIN OUTCOME MEASURES

Hypotheses were as follows: (1) no differential item response would be found on the motor or process scales; (2) if differential item response was found, it would not have an impact on the final estimation of client ability; (3) men and women would not differ in mean AMPS motor or process ability.

RESULTS

Of the 36 AMPS items, only one (Lifts) differed between men and women. This differential item response did not disrupt the final estimation of client ability. Men and women did not differ in mean motor ability. Women on the whole were more able than men in mean process ability.

CONCLUSIONS

The AMPS is valid for use across gender subgroups. Men and women do not differ in AMPS motor ability, but overall, women are slightly more able than men in AMPS process ability.

Differences between persons with right or left cerebral vascular accident on the Assessment of Motor and Process Skills

OBJECTIVE

Persons with right and left cerebral vascular accident (RCVA and LCVA) differ in terms of discrete impairments, but there is limited information with regard to how such impairments translate into differences in disability. The following hypotheses were tested: (1) persons with stroke have lower instrumental or domestic activities of daily living (IADL) ability than do matched nondisabled controls, (2) persons with RCVA do not differ from persons with LCVA in IADL ability, and (3) persons with RCVA and LCVA differ in specific motor and process skills that affect IADL performance.

DESIGN

Descriptive comparison.

SETTING

Subjects were tested in settings where rehabilitation services were received (home or clinic).

SUBJECTS

71 persons with RCVA, 76 persons with LCVA, and 83 community-living nondisabled individuals drawn from the Assessment of Motor and Process Skills (AMPS) database, matched for age, gender, and number of tasks performed.

MAIN OUTCOME MEASURE

AMPS, designed to measure type and severity of impairments manifested in the context of IADL performance. The AMPS was administered to all subjects in accordance with standardized testing procedures.

RESULTS

The two stroke groups did not differ significantly in IADL ability, but both stroke groups had significantly lower IADL performance than did the nondisabled subjects. On the AMPS motor scale, persons with RCVA demonstrated greater impairment in pacing, transporting, and coordinating two body parts. Persons with LCVA demonstrated greater impairments in calibrating movements. No differences were found between the two groups in AMPS process skills.

CONCLUSIONS

Persons with RCVA and LCVA have hemisphere-specific differences in motor impairments, but do not differ significantly in IADL ability.

Lymphoproliferative disorders in IL-7 transgenic mice: expansion of immature B cells which retain macrophage potential

Transgenic mice carrying the murine IL-7 gene under the MHC class II (E alpha) promoter are described which develop lymphoid tumours at a high incidence when maintained in conventional or specific pathogen-free environments. Cells obtained from the lesions were relatively monomorphic, expressed a variety of B cell associated markers (BP-1, B220, CD43) but lacked surface Ig. Some mice, showed expanded populations of cells phenotypically similar to the recently reported bipotent B/macrophage stem cell subset (AA4.1high, B220-, Ig-) which could be cloned and maintained in vitro. These cells expressed IL-7 receptors, proliferated in response to IL-7 and in most cases had germline configuration of the Ig heavy chain locus. Cell lines cloned from two such tumours generated macrophages spontaneously in culture, consistent with their bipotent B cell/macrophage phenotype. These results suggest that IL-7 plays a role in very early stages of B cell ontogeny prior to bona fide B cell commitment.

Expression of functional MHC class II molecules by a mouse pro-B cell clone

We describe here the G12 pro-B cell clone that has been isolated from an IL-7 transgenic mouse. This clone has the phenotype B220+, BP-1+, HSA+, CD43+, lambda5+, and CD25-, and has its Ig locus in a germline configuration. G12 cells spontaneously express cell-surface MHC class II molecules, although to a much lesser extent than the mature M12.4.1 B-cell lymphoma. G12 cells can process and present the native Hen Egg Lysozyme (HEL) to an MHC class II-restricted T-cell hybridoma. The efficiency of presentation is inferior to that obtained with M12.4.1 cells. This is the first report where a pro-B cell can serve as APC in an MHC class II-restricted presentation.

Does the Q angle reflect the force on the patella in the frontal plane?

BACKGROUND AND PURPOSE

The quadriceps femoris muscle angle (Q angle) is used to reflect the quadriceps femoris muscle's force on the patella in the frontal plane. We found no studies, however, that validate this assumption. The purpose of this study was to determine whether the Q angle can be used to represent the force on the patella in the frontal plane.

SUBJECTS

Seven lower extremities from four male cadavers were dissected and investigated.

METHODS

We devised a model in which the line of action of quadriceps femoris muscle's resultant force was calculated in the frontal plane on the seven lower-extremity specimens. We then compared these calculations with the Q angles from the same cadaver specimens. The differences between the measured and calculated Q angles were tested for significance using a paired t test. In addition, we calculated a simple linear regression to test the relationship between the calculated and measured Q angles.

RESULTS

Our data showed that the angle for the average resultant force of the quadriceps femoris muscle was 3.90 degrees greater (P = .0003) than the measured Q angles. A significant relationship (r = .919, P = .0035); however, was found between the measured and calculated Q angles.

CONCLUSION AND DISCUSSION

The Q angle, as measured in clinical practice, appears to reflect the angle of the resultant quadriceps femoris muscle force. We believe, however, that this measurement is significantly less than the actual quadriceps femoris muscle force vector and underestimates the lateral force on the patella.

The Assessment of Motor and Process Skills of persons with psychiatric disorders

OBJECTIVES

The purpose of this study was to examine the discriminant validity of the Assessment of Motor and Process Skills (AMPS) when used to evaluate a heterogeneous sample of subjects with psychiatric disorders.

METHOD

Sixty subjects, ranging in age from 16 to 72 years, participated in this study; 30 were persons without disorders living in the community; 30 had diagnosed psychiatric disorders. Two univariate F tests were used to test the hypothesis that mean AMPS measures would differ significantly between the group with and the group without psychiatric disorders.

RESULTS

The hypothesis was supported for both AMPS motor and process scale measures. As would be expected among a sample that includes many higher functioning persons, many subjects with psychiatric disorders did just as well as subjects in the group without psychiatric disorders.

CONCLUSIONS

Motor as well as process skill abilities of persons with psychiatric disorders should be evaluated. Because the AMPS provides more specific features than other global functional instruments, it can help clinicians plan treatment and intervention more effectively. Further examination of the motor and process skill deficits within and among diagnostic subgroups and of the effect of medication and prolonged hospitalization on AMPS motor and process abilities is indicated.

Comparing motor and process ability of persons with suspected dementia in home and clinic settings

OBJECTIVES

Evaluating functional level of persons with diagnosed or suspected dementia is an important part of occupational therapy. The importance of the environment is often highlighted. We investigated the ability of clients with suspected dementia to perform instrumental activities of daily living (IADLs) in the clinic versus in their homes.

METHOD

We used the Assessment of Motor and Process Skills (AMPS) to measure the motor and process skill ability of 19 clients with suspected dementia.

RESULTS

Using two-tailed paired t-tests, we found no overall difference in IADL motor or process performance between the clinic and home setting. However, of the 19 clients, 6 had motor ability measures, whereas 5 had process ability measures that differed significantly between the two settings.

CONCLUSION

The results suggest that if we want to know how a person with suspected dementia performs in IADLs in a specific environment we should test him or her in that environment.

Using the assessment of motor and process skills to compare occupational performance between clinic and home settings

OBJECTIVES

The study described in this article examined the effect of home versus clinic settings on the instrumental activities of daily living (IADL) performance of older adults.

METHOD

Twenty older adults living in the community were evaluated in their homes and in an occupational therapy clinic with the Assessment of Motor and Process Skills (AMPS). The motor and process ability measures were compared between the two settings with many-faceted Rasch analysis.

RESULTS

The subjects' motor ability measures tended to remain stable from clinic to home settings. The process ability measures tended not to remain stable from clinic to home settings, because 10 of the 20 subjects performed significantly better in their homes.

CONCLUSION

These findings support the idea that process skill abilities are affected by the environment to a greater degree than are motor skills abilities and that for persons living in the community, the familiar home environment tends to support IADL performance. If an occupational therapist wants to know how a person performs IADLs, the therapist should evaluate that person's performance in the environment in which the client will be functioning.

Functional competence of community-dwelling persons with multiple sclerosis using the assessment of motor and process skills

The Assessment of Motor and Process Skills (AMPS) is an observational measure of functional competence in instrumental activities of daily living (IADL) that was designed to overcome the limitations of self reports and proxy reports. The AMPS allows simultaneous evaluation of the underlying motor and process (organizational/adaptive) skills necessary for competent task performance. We examined the IADL performance of 22 community-dwelling patients with mild to moderate MS in comparison to nondisabled subjects matched for age and gender. Functional competence of the MS subjects, as measured by the AMPS, was poorer than that of the control group. Many MS subjects who would not have been expected to have IADL difficulties on the basis of ratings of neurologic impairment were impaired in their IADL performance. For some patients, IADL impairment reflected deficits in their motor and process skills, whereas for others, process skill impairments alone were responsible for deficient task performance.

The effects of different percentages of dietary fat intake, exercise, and calorie restriction on body composition and body weight in obese females

PURPOSE

The goal of this study was to determine the effect of varying the amount of dietary fat, while holding calories at 1,200 kcals/day, on body weight and percent body fat in 35 obese women.

DESIGN

A pretest, midtest, posttest experimental design was employed, and subjects were randomly divided into one of four dietary fat groups, with 10%, 20%, 30%, or 40% of caloric intake as dietary fat.

INTERVENTION

Subjects consumed 1,200 kcals/day and a specified percentage of total energy as fat, depending on their dietary group. Protein was held constant at 20%. All subjects engaged in a five day/week walking program.

SETTING

Participants were recruited from the general community using newspaper advertisements.

SUBJECTS

Thirty-five obese women 25 to 45 years of age (means=38 +/- 4.97) served as subjects. All were at least 20% above ideal weight and 30% to 52% body fat.

MEASURES

Percent body fat, body weight, and anthropomorphic measurements were taken at baseline, six and 12 weeks. Dietary intake was recorded daily by each subject, and exercise walking logs were maintained by each participant.

RESULTS

All subjects lost body weight and body fat; however, there were no significant differences in the rate or amount of body weight or percent body fat lost across the four groups during the intervention.

CONCLUSIONS

It appears that during calorie restriction and exercise for 12 weeks, percent of calories derived from dietary fats does not influence loss of body weight or percent body fat in adult obese women.