Validity and reliability of the 2-min step test in individuals with stroke and lower-limb musculoskeletal disorders.

Introduction: We investigated the reliability and validity of the 2-min step test (2MST) for assessing the exercise endurance of individuals with stroke and lower-limb musculoskeletal disorders. Participants and methods: The participants were 39 individuals with stroke and 42 with lower-limb musculoskeletal disorders (mainly hip fractures) from the convalescent rehabilitation wards of four hospitals. The concurrent validity and congruence between the 2MST and the 6-min walk test (6MWT) and construct validity by hypotheses testing, including mobility and lower limb muscle strength, were also confirmed. A subset of participants (stroke-group, n = 15; musculoskeletal-group, n = 19) underwent a retest 2MST for our evaluation of relative and absolute reliability using the intraclass correlation coefficient (ICC1,1) and Bland-Altman plot. Results: Both groups showed a moderate correlation between the 2MST and 6MWT (ρ = 0.55-0.60), but the congruence was not sufficient. The 6MWT was correlated with mobility in both groups and with muscle strength in the stroke group, whereas the 2MST did not show a significant correlation with mobility. The relative reliability was excellent in both groups (ICC1,1 > 0.9). In terms of absolute reliability, the width of the limit of agreement was 18.8% for the stroke group and 15.4% for the musculoskeletal group, relative to their respective sample means of 2MST. A fixed bias was identified in the stroke group, in which step counts increased by 6.5 steps upon retesting. Discussion: Our analyses revealed that the 2MST is a valid and reliable tool for assessing the exercise endurance of individuals with stroke or lower-limb musculoskeletal disorders. However, it is necessary to validate the absolute reliability observed herein by using a larger sample size. In addition, when assessing the exercise endurance of individuals with stroke, it may be necessary to consider the potential bias of an increased step count during retesting.

Physical activity according to sit-to-stand, standing, and stand-to-sit abilities in subacute stroke with walking difficulty: a cross-sectional study.

OBJECTIVE: This study investigated the characteristics of physical activity according to sit-to-stand, standing, and stand-to-sit abilities in subacute stroke with walking difficulty. METHODS: In this study, 29 participants with subacute stroke and walking difficulty were enrolled and classified into two groups: participants who successfully completed three items (i.e., sit-to-stand, standing, and stand-to-sit) of the Functional Balance Scale (independent group, n = 13) and those who showed incomplete scores on any of the three items (dependent group, n = 16). Light-intensity physical activity (LIPA) and moderate-to-vigorous physical activity (MVPA) were measured using an accelerometer at three periods (i.e. daytime, therapy time, and non-therapy time) for a week. RESULTS: Two-way analysis of variance (groups × physical activity intensity) demonstrated a significant interaction in each period. Post-hoc tests showed significantly more LIPAs and MVPAs in the independent group in all periods, except for MVPA in the non-therapy time. Particularly, LIPA showed significant between-group differences in each period. CONCLUSIONS: Among individuals with subacute stroke and walking difficulty, those who could completely perform sit-to-stand, standing, and stand-to-sit could perform more LIPAs. Increasing sit-to-stand, standing, and stand-to-sit abilities could be an important factor in increasing the opportunity to perform LIPAs.

Reliability of measurement using Image J for reach distance and movement angles in the functional reach test.

[Purpose] The purpose of this study was to examine the test-retest reliability and minimal detectable change (MDC) of reach distance and movement angle analyses using Image J. [Participants and Methods] Thirty-eight healthy young males performed the functional reach test (FRT) twice, and their reach movements were recorded using a digital video camera. Image J was used to combine the digital photographs taken at the start position and maximum reach and to measure each movement. The measurements recorded were the movement distance of the third metacarpal bone (reach distance), anterior-superior iliac spine, and trochanter major, and the angles recorded were the acromion-malleolus lateralis, acromion-trochanter major, and trochanter major-malleolus lateralis. The reliability of all the measurements was analyzed using intraclass correlation coefficients (ICCs), Bland-Altman plots, and MDCs. [Results] The ICCs (1, 1) were >0.80 for all the outcomes. The Bland-Altman analysis revealed no systematic bias in any outcome. The MDC of reach distance was 18.3 mm. [Conclusion] Measurement using Image J for reach distance and movement angles in the FRT showed acceptable high test-retest reliability. Measurement of the FRT and the MDC calculated in this study could be used as a reference for further research.

Daytime physical activity at admission is associated with improvement of gait independence 1 month later in people with subacute stroke: a longitudinal study.

Background: Little is known about the benefits of daytime physical activity on gait ability in subacute stroke.Objectives: We investigated association between daytime physical activity at hospital admission and improvement of gait independence 1 month later in subacute stroke.Methods: Thirty-four participants with subacute stroke who could not walk independently were assessed. An accelerometer (HJA 350-IT, OMRON) was used to record the mean duration of light-intensity physical activity (LIPA) and moderate-to-vigorous-intensity physical activity (MVPA). LIPA and MVPA were recorded for 12 h per day for 7 consecutive days, and at three different time periods (daytime, therapy time, non-therapy time) at rehabilitation hospital admission (baseline). Gait independence was assessed by the functional ambulation category (FAC) at baseline and 1 month later. Participants were categorized into two groups based on the change of gait independence, as follows: the improved group, in which the FAC increased by ≥1; the non-improved group, in which the FAC did not increase.Results: Compared with the non-improved group, the improved group demonstrated significantly higher values of all physical activity variables, except for non-therapy time MVPA (p < .05). Logistic regression analysis showed that higher daytime LIPA was significantly associated with FAC improvement (OR = 1.068, 95% CI 1.009 to 1.140). In particular, higher non-therapy time LIPA was closely associated with FAC improvement (OR = 1.253, 95% CI 1.002 to 1.568).Conclusions: To promote recovery of gait independence in first month from admission, increasing daytime physical activity, especially LIPA during daytime or non-therapy time, is an important treatment target in subacute stroke.

Characteristics of intensity-based physical activity according to gait ability in people hospitalized with subacute stroke: a cross-sectional study.

OBJECTIVE: Gait ability may be related to the level of intensity-based physical activity in people who have experienced a stroke; however, this relationship has not been explored in previous studies. This study aimed to investigate the characteristics of intensity-based physical activity according to gait ability and to explore the factors related to different intensity physical activity. METHOD: Eighty hospitalized participants with subacute stroke were assigned to three groups based on their gait ability: group 1 (n = 28) could walk independently with a maximal gait speed (MGS) of more than 0.9 m/s; group 2 (n = 11) could walk independently with a MGS of less than 0.9 m/s; group 3 (n = 41) could not walk independently. Light-intensity physical activity (LIPA) and moderate-to-vigorous physical activity (MVPA) were measured for 12 hours using an accelerometer (OMRON, HJA350-IT) for 7 consecutive days and were calculated throughout three time periods (daytime, non-therapy time, or therapy time). RESULTS: In each time period, a two-way ANOVA showed an interaction between the groups and intensity-based physical activity (p < 0.05). Bonferroni post hoc test showed a significantly higher LIPA in groups 1 and 2 compared with group 3 in daytime or non-therapy time. In contrast, group 1 showed a significantly higher MVPA compared with group 2 and 3 for each time period. CONCLUSION: During daytime and non-therapy time, the results suggested that gait independence is related to LIPA rather than gait speed, and gait speed and gait independence is related to MVPA.

Early effects of a knee-ankle-foot orthosis on static standing balance in people with subacute stroke.

[Purpose] The purpose of this study was to evaluate the early effects of a knee-ankle-foot orthosis on static standing balance in people with subacute stroke. [Participants and Methods] Timed static standing balance in four standing conditions (feet apart with eyes open, feet apart with eyes closed, feet together with eyes open, and tandem stance with eyes open) was assessed in 29 inpatients (mean age: 67.3 ± 13.3 years) with subacute stroke with and without a knee-ankle-foot orthosis on the paretic lower limb. [Results] In the group of participants who were unable to stand without a knee-ankle-foot orthosis, the proportion of participants who were able to stand with a knee-ankle-foot orthosis was significantly increased in the following conditions: feet apart with eyes open and feet apart with eyes closed. In the group of participants who were able to stand without a knee-ankle-foot orthosis, the mean duration of time for which the participants with a knee-ankle-foot orthosis were able to stand was significantly longer than that for those without a knee-ankle-foot orthosis for all standing conditions. [Conclusion] A knee-ankle-foot orthosis may be a useful assistive device to support static standing balance for people with subacute stroke.

p-n Control of AlMgB14-Based Thermoelectric Materials by Metal Site Occupancy.

The mechanism for the p-n control of AlMgB14-based thermoelectric material was investigated using Rietveld refinement and the first principle calculation. The p- and n-type AlMgB14-based thermoelectric materials were prepared by spark plasma sintering (SPS) with changing raw powder mixture ratio. Temperature dependence of Seebeck coefficient and electrical conductivity were different between the two types of samples. Seebeck coefficient shifted from positive to negative with increasing the number of valence electrons in the metal sites calculated by the metal site occupancy. The density of states and electron density distribution indicated that the electrons transfer from metal atoms to the B atoms.

Differences in activities of daily living between people with subacute stroke who received knee-ankle-foot and ankle-foot orthoses at admission.

[Purpose] This study aimed to identify the preferential factor of activities of daily living disabilities for selecting between knee-ankle-foot orthosis and ankle-foot orthosis prescription in the early stage after admission. [Participants and Methods] This study included 442 inpatients who had a subacute stroke and received either knee-ankle-foot orthosis or ankle-foot orthosis after admission (mean age, 69 years). The functional independence measure was investigated within 1 week after admission. [Results] Inpatients who had a stroke and received knee-ankle-foot orthosis had significantly lower scores for all individual functional independence measure items than those who received ankle-foot orthosis. Logistic regression analysis revealed that functional independence measure transfer (bed, chair, and wheelchair) was closely associated with the difference in the prescribed lower limb orthosis after multivariate adjustment. [Conclusion] Compared with ankle-foot orthosis, knee-ankle-foot orthosis was prescribed to inpatients with more-severe disabilities, and the difference in the disability related to performing transfer activities was more noticeable than that in disability related to mobility between inpatients for whom knee-ankle-foot orthosis was prescribed and those for whom ankle-foot orthosis was prescribed. To provide effective rehabilitation for people who had a subacute stroke, for whom use of knee-ankle-foot orthosis or ankle-foot orthosis is recommended. The evaluation and intervention focused on standing performance related to performing transfer such as sit-to-stand, standing, moving while standing, and stepping might be a priority in the early stage after admission.

Difference in independent mobility improvement from admission to discharge between subacute stroke patients using knee-ankle-foot and those using ankle-foot orthoses.

[Purpose] To verify differences in independent mobility improvements between people with subacute stroke with knee-ankle-foot orthoses (KAFOs) and those with ankle-foot orthoses (AFOs) from admission to discharge, and to identify the relationship between mobility improvements and their characteristics. [Participants and Methods] This study included 381 hospitalized patients with subacute stroke who required complete mobility assistance at admission and for whom KAFOs (KAFO group) or AFOs (AFO group) were prescribed after admission. The functional independence measure (FIM) score at admission and discharge, FIM gain, age, Brunnstrom stage (BS) of the paretic lower limb at admission, and the period from admission to prescription for lower limb orthoses were investigated. [Results] Repeated-measures two-way analysis of variance revealed a significant group × time interaction in the walk/wheelchair and stair-climbing items of the FIM. Improvements in the scores in the KAFO group were significantly lower than those in the AFO group. Age, BS, FIM at admission, and period from admission to lower limb orthosis prescription significantly correlated with FIM gain in the walk/wheelchair and stair-climbing items. [Conclusion] A more effective intervention using lower limb orthoses with consideration of the influence of age, motor paralysis, and activities of daily living at admission is required to promote the improvements of people with subacute stroke prescribed KAFOs or AFOs.

The known-groups validity of intensity-based physical activity measurement using an accelerometer in people with subacute stroke.

[Purpose] This study aimed to assess the known-groups validity of the estimated metabolic equivalents during physical activities using accelerometer, Active Style Pro HJA 350-IT, in people with subacute stroke. [Subjects and Methods] Ten participants with subacute stroke and ten healthy people performed six activities (lying, sitting, standing, sitting with reaching task, standing with reaching task, and walking) and metabolic equivalents were estimated using the accelerometer during each activity. These estimated metabolic equivalents were compared with reported metabolic equivalents through compendiums or previous studies. Additionally, the estimated metabolic equivalents were compared between subacute stroke and healthy control participants. [Results] The estimated metabolic equivalents of both groups during maintaining posture showed significantly lower values in comparison with previous studies. There were no significant differences between the estimated metabolic equivalents during sitting with reaching tasks or standing with reaching tasks when compared with compendium metabolic equivalents across both groups. The estimated metabolic equivalents during walking were inevitable values significantly differed from previous study which conducted with stroke patients with lower gait abilities in both groups. [Conclusion] The estimated metabolic equivalents using accelerometer may be suitable to assess movement activity rather than motionless activity, and accelerometer demonstrated acceptable validity in people with subacute stroke.

Reliability of intensity-based physical activity measurement using an activity monitor in people with subacute stroke in the hospital setting: a cross-sectional study.

Background Activity monitors are known to provide quantitative evaluation of physical activity in people with stroke. However, little evidence is available on the test-retest reliability and suitable measuring conditions for evaluating physical activity with an activity monitor in people with subacute stroke at a hospital setting. Objectives To evaluate reliability of physical activity measurement using an activity monitor in different measuring conditions in hospitalized people with subacute stroke according to gait ability. Methods Sixty-nine participants with subacute stroke were categorized based on their gait ability: group 1 (n = 22), could walk independently at sufficient gait speed (≥0.9 m/s); group 2 (n = 11), could walk independently with insufficient gait speed (<0.9 m/s); group 3 (n = 36), required assistance in walking. Physical activity (sedentary behavior, light-intensity physical activity, moderate-to-vigorous physical activity) was measured using an activity monitor (OMRON, HJA350-IT) for seven consecutive days. All physical activity variables were calculated in five conditions defined according to measurement periods (3, 5, or 7 days with or without weekends). Results In groups 1 and 2, intraclass correlation coefficients were high across all measuring conditions in all physical activity variables (>0.7). In group 3, intraclass correlation coefficients were high in all measuring conditions (>0.7) except for three weekdays measuring condition (0.563-0.922). Conclusions In hospitalized people with subacute stroke, the central tendency of intensity-based physical activity could be assessed with good reliability using an activity monitor. For reliable measurement, more measurement days are needed in those with dependent walking compared to those with independent walking.

An application of cascaded 3D fully convolutional networks for medical image segmentation.

Recent advances in 3D fully convolutional networks (FCN) have made it feasible to produce dense voxel-wise predictions of volumetric images. In this work, we show that a multi-class 3D FCN trained on manually labeled CT scans of several anatomical structures (ranging from the large organs to thin vessels) can achieve competitive segmentation results, while avoiding the need for handcrafting features or training class-specific models. To this end, we propose a two-stage, coarse-to-fine approach that will first use a 3D FCN to roughly define a candidate region, which will then be used as input to a second 3D FCN. This reduces the number of voxels the second FCN has to classify to ∼10% and allows it to focus on more detailed segmentation of the organs and vessels. We utilize training and validation sets consisting of 331 clinical CT images and test our models on a completely unseen data collection acquired at a different hospital that includes 150 CT scans, targeting three anatomical organs (liver, spleen, and pancreas). In challenging organs such as the pancreas, our cascaded approach improves the mean Dice score from 68.5 to 82.2%, achieving the highest reported average score on this dataset. We compare with a 2D FCN method on a separate dataset of 240 CT scans with 18 classes and achieve a significantly higher performance in small organs and vessels. Furthermore, we explore fine-tuning our models to different datasets. Our experiments illustrate the promise and robustness of current 3D FCN based semantic segmentation of medical images, achieving state-of-the-art results.1.

Unique hyper-thermal composting process in Kagoshima City forms distinct bacterial community structures.

A unique compost, Satsuma soil, is produced from three types of wastewater sludge using hyper-thermal processes at temperatures much higher than that of general thermophilic processes in Kagoshima City, Japan. We analyzed the bacterial community structures of this hyper-thermal compost sample and other sludges and composts by a high-throughput barcoded pyrosequencing method targeting the 16S rRNA gene. In total, 621,076 reads were derived from 17 samples and filtered. Artificial sequences were deleted and the reads were clustered based on the operational taxonomic units (OTUs) at 97% similarity. Phylum-level analysis of the hyper-thermal compost revealed drastic changes of the sludge structures (each relative abundance) from Firmicutes (average 47.8%), Proteobacteria (average 22.3%), and Bacteroidetes (average 10.1%) to two main phyla including Firmicutes (73.6%) and Actinobacteria (25.0%) with less Proteobacteria (∼0.3%) and Bacteroidetes (∼0.1%). Furthermore, we determined the predominant species (each relative abundance) of the hyper-thermal compost including Firmicutes related to Staphylococcus cohnii (13.8%), Jeotgalicoccus coquinae (8.01%), and Staphylococcus lentus (5.96%), and Actinobacteria related to Corynebacterium stationis (6.41%), and found that these species were not predominant in wastewater sludge. In contrast, we did not observe any common structures among eight other composts produced, using the hyper-thermal composts as the inoculums, under thermophilic conditions from different materials. Principle coordinate analysis of the hyper-thermal compost indicated a large difference in bacterial community structures from material sludge and other composts. These results suggested that a distinct bacterial community structure was formed by hyper-thermal composting.

Rationality/anti-emotionality personality and dietary habits in a community population in Japan.

BACKGROUND: There are no strong and consistent predictors of dietary habits although some associations have been shown with psychological factors. The purpose of the present study was to examine the relationships between the rationality and anti-emotionality (R/A) personality and dietary consumption in a Japanese community. METHODS: The Takayama study is a community-based cohort study on diet and cancer in Gifu, Japan, and was initiated on September 1, 1992. Cross-sectional analyses were conducted on dietary and lifestyle data. The consumption of 169 food and beverage items was measured along with portion size by using a food frequency questionnaire. Questions regarding the R/A-personality scale and lifestyle habits were included in the questionnaire. The participants were 28077 adults (13082 males and 14995 females) aged 35 years and over. RESULTS: Both males and females with high R/A-personality scores (i.e., high degree of rational thought and emotional repression) consumed more soy products, green and yellow vegetables, other vegetables, and seaweed than the other participants. Males with high R/A-personality scores drank fewer alcoholic beverages, and females with high scores were found to snack less on sweet and salty foods than the other participants. Males with high R/A-personality scores showed higher consumption of meat and dairy products, and females with high scores showed higher consumption of fish, shellfish, and eggs than those with low R/A-personality scores. CONCLUSION: The R/A-personality scale may differentiate dietary habits in males and females in a Japanese community.

Emergence of delayed methylmercury toxicity after perinatal exposure in metallothionein-null and wild-type C57BL mice.

BACKGROUND: Although a long latency period of toxicity after exposure to methylmercury (MeHg) is known to exist in humans, few animal studies have addressed this issue. Substantiation of delayed MeHg toxicity in animals would affect the risk evaluation of MeHg. OBJECTIVES: Our goal in this study was to demonstrate the existence of a latency period in a rodent model in which the toxicity of perinatal MeHg exposure becomes apparent only later in life. Our study included metallothionein (MT) knockout mice because studies have suggested the potential susceptibility of this strain to the neurodevelopmental toxicity of MeHg. METHODS: Pregnant MT-null and wild-type C57Bl/6J mice were exposed to MeHg through their diet containing 5 mug Hg/g during gestation and early lactation. We examined behavioral functions of the offspring using frequently used paradigms, including open field behavior (OPF), passive avoidance (PA), and the Morris water maze (MM), at ages of 12-13 and 52-53 weeks. RESULTS: At 12 weeks of age, behavioral effects of MeHg were not detected, except for OPF performance in MeHg-exposed MT-null females. At 52 weeks of age, the MeHg-exposed groups showed poorer performance both in PA and MM, and their OPF activity differed from controls. These effects of MeHg appeared exaggerated in the MT-null strain. The brain Hg concentration had leveled off by 13 weeks of age. CONCLUSIONS: The results suggest the existence of a long latency period after perinatal exposure to low-level MeHg, in which the behavioral effects emerged long after the leveling-off of brain Hg levels. Hence, the initial toxicologic event responsible for the late effects should have occurred before this leveling-off of brain Hg.

Soy product consumption and the risk of colon cancer: a prospective study in Takayama, Japan.

The relationship of the intake of soy products and the incidence of colon cancer was prospectively evaluated in a population-based cohort study in Japan. The total intake of soy products and isoflavones in a daily diet was estimated from a validated questionnaire administered at the baseline. The participation rate of the questionnaire was 92.0%. The participants were followed from 1992 to 2000, and colon cancer diagnoses were identified at the main hospitals in the study area. In the analysis, 13,894 men and 16,327 women were included. The medians for energy-adjusted soy product intake were 85.52 g/day for men and 79.60 g/day for women. During follow-up, 111 men and 102 women were diagnosed with colon cancer. A Cox-proportional hazard model was applied to assess the risk of colon cancer incidence. Among women, the risk was reduced with an increased soy product consumption; the hazard ratio in the highest tertile was 0.56 (95% CI 0.34-0.92) compared as the lowest tertile (trend: P=0.04), after adjusting for multiple potential confounders. Among men, no significant association was observed. Our results exhibited the weak benefit of soy foods only among women. Further research to confirm our results may be beneficial.

The relationship between the consumption of meat, fat, and coffee and the risk of colon cancer: a prospective study in Japan.

The risk of the development of colon cancer in relation to a western diet was studied in a community-based cohort in Japan. From 1992 to 2000, 13,894 men and 16,327 women were followed. In men, high consumption of processed meat increased the risk in comparison with low consumption (adjusted RR=1.98, 95% CI: 1.24-3.16). In women, daily coffee drinkers had a reduced risk in comparison with individuals who never or rarely drank coffee (adjusted RR=0.43, 95% CI: 0.22-0.85). The findings suggest the possible linkage between a western diet and risk of colon cancer.

Soy, fat and other dietary factors in relation to premenstrual symptoms in Japanese women.

OBJECTIVE: To evaluate the relations of intakes of soy, fat and other dietary components to premenstrual symptoms. DESIGN: Cross sectional study. SETTING: Three colleges and two nursing schools. POPULATION: One hundred and eighty-nine Japanese women aged 19 to 34 years. METHODS: Intakes of nutrients and foods, including soy products and isoflavones, were estimated by a semiquantitative food frequency questionnaire. Change in menstrual cycle symptoms were assessed by the Moos Menstrual Distress Questionnaire (MDQ). MAIN OUTCOME MEASURES: Spearman rank correlation of soy and other dietary factors with changes in MDQ scores between the follicular and the premenstrual phases after controlling for age, marital status, exercise, smoking status, age at menarche and number of days of bleeding. RESULTS: Neither soy product nor isoflavone intake was significantly associated with change in MDQ score in the premenstrual phase. Intakes of total, saturated and monounsaturated fats were significantly correlated with change in scores for total MDQ and subscale 'pain' in the premenstrual phase after controlling for the covariates. Intake of cereals/potatoes/starches was significantly inversely correlated with a change in total MDQ score in the premenstrual phase. CONCLUSIONS: High intake of fats and low intake of foods with high concentration of carbohydrate may be associated with premenstrual symptoms.

Sodium intake and risk of death from stroke in Japanese men and women.

BACKGROUND AND PURPOSE: Despite the evidence for a positive association of dietary salt and blood pressure, the few prospective studies that have assessed the association between dietary salt and stroke have reported inconsistent results. The purpose of this study was to examine the relation between sodium intake and death from stroke in a population-based cohort of Japanese men and women. METHODS: In 1992, usual diet including sodium intake was determined in 13 355 men and 15 724 women in Takayama City, Gifu, with the use of a validated food frequency questionnaire. RESULTS: There were 269 stroke deaths (137 men and 132 women) between baseline and 1999. In men, the highest compared with the lowest tertile of sodium intake was significantly positively associated with death from total stroke after controlling for covariates (hazard ratio [HR]), 2.33; 95% CI, 1.23 to 4.45). Significantly positive associations were also observed between sodium intake and death from ischemic stroke (HR, 3.22; 95% CI, 1.22 to 8.53) as well as death from intracerebral hemorrhage (HR, 3.85; 95% CI, 1.16 to 12.7). A positive association between sodium intake and death from stroke in women was suggested, although the associations for total stroke and ischemic stroke were of borderline significance (HR, 1.70; 95% CI, 0.96 to 3.02 and HR, 2.10; 95% CI, 0.96 to 4.62, respectively). CONCLUSIONS: These prospective data support the hypothesis that dietary salt increases the risk of death from stroke.