Gaussian mixture modeling of acceleration-derived signal for monitoring external physical load of tennis player.

Introduction: With the widespread use of wearable sensors, various methods to evaluate external physical loads using acceleration signals measured by inertial sensors in sporting activities have been proposed. Acceleration-derived external physical loads have been evaluated as a simple indicator, such as the mean or cumulative values of the target interval. However, such a conventional simplified indicator may not adequately represent the features of the external physical load in sporting activities involving various movement intensities. Therefore, we propose a method to evaluate the external physical load of tennis player based on the histogram of acceleration-derived signal obtained from wearable inertial sensors. Methods: Twenty-eight matches of 14 male collegiate players and 55 matches of 55 male middle-aged players wore sportswear-type wearable sensors during official tennis matches. The norm of the three-dimensional acceleration signal measured using the wearable sensor was smoothed, and the rest period (less than 0.3 G of at least 5 s) was excluded. Because the histogram of the processed acceleration signal showed a bimodal distribution, for example, high- and low-intensity peaks, a Gaussian mixture model was fitted to the histogram, and the model parameters were obtained to characterize the bimodal distribution of the acceleration signal for each player. Results: Among the obtained Gaussian mixture model parameters, the linear discrimination analysis revealed that the mean and standard deviation of the high-intensity side acceleration value accurately classified collegiate and middle-aged players with 93% accuracy; however, the conventional method (only the overall mean) showed less accurate classification results (63%). Conclusion: The mean and standard deviation of the high-intensity side extracted by the Gaussian mixture modeling is found to be the effective parameter representing the external physical load of tennis players. The histogram-based feature extraction of the acceleration-derived signal that exhibit multimodal distribution may provide a novel insight into monitoring external physical load in other sporting activities.

Physical functions associated with health-related quality of life in older adults diagnosed with knee osteoarthritis.

[Purpose] The present study aimed to identify the physical functions associated with health-related quality of life in older adults with knee osteoarthritis. [Participants and Methods] A total of 132 participants were included in this study in two groups: the knee osteoarthritis group (n=66) and the control group (n=66). We compared the results of the Medical Outcomes Study 36-Item Short-Form Health Survey with the physical function measures related to health-related quality of life. In the knee osteoarthritis group, we examined the relationship between the degree of knee pain and health-related quality of life. [Results] The knee osteoarthritis group showed a significantly shorter one-leg standing time, lower maximum walking speed, and significantly longer time to complete the Sit-to-Stand-5 and Timed Up and Go tests than the control group. The knee osteoarthritis group had significantly lower 36-Item Short-Form Health Survey scores than the control group on seven subscales and significantly lower scores for physical component summary and role or social component summary. In the knee osteoarthritis group, physical component summary and role or social component summary were correlated with Sit-to-Stand-5, Timed Up and Go, and maximum walking speed. We observed a correlation between physical component summary and knee pain on joint loading. [Conclusion] In older adults with knee osteoarthritis, rehabilitation approaches aimed at achieving a smooth transition from sitting to standing may increase social participation and improve health-related quality of life.

Olfactory identification ability in patients with mild cognitive impairment and Alzheimer's disease.

[Purpose] To examine the olfactory identification abilities and specify the difficult-to-identify odors in community-dwelling individuals with mild cognitive impairment (MCI) and Alzheimer's disease (AD). [Participants and Methods] We included, 12 and 17 patients with MCI (MCI group) and AD (AD group), respectively, and 30 community-dwelling older adults with no history of MCI or a dementia diagnosis (control group). Scores on the Japanese odor stick identification test (OSIT-J), an olfactory identification ability test, were compared among the three groups with intergroup differences examined accordingly. Next, we performed intergroup comparisons of the ratios of correct responses for each odor, and the difficult-to-identify odors were examined. [Results] OSIT-J scores of the MCI and AD groups were significantly lower than those of the control group. There were no intergroup differences in the correct identification of pungent odors. No patients in the AD group could identify the odor of cooking gas. The ability to identify food-related odors was reduced in the MCI and AD groups. [Conclusion] Patients with MCI and AD had reduced olfactory identification abilities in comparison to community-dwelling older adults without cognitive decline. These findings suggest the importance of olfactory evaluation before providing patients with dementia with therapeutic interventions associated with olfactory stimuli.

Association between cognitive function and olfactory identification ability in community-dwelling older individuals.

[Purpose] We investigated whether olfactory identification ability may be useful for early detection of cognitive decline. [Participants and Methods] The study included 55 community-dwelling older individuals without a history of mild cognitive impairment or dementia, who were capable of living independently. Cognitive function was evaluated using the Japanese versions of the Mini-Mental State Examination and the Montreal Cognitive Assessment tools. The olfactory identification ability was evaluated using the Odor Stick Identification Test for the Japanese. We also investigated the association between olfactory identification ability and cognitive function. [Results] Based on the Japanese version of the Mini-Mental State Examination, all participants were categorized into the noncognitive decline group, and based on the Japanese version of the Montreal Cognitive Assessment tool, 21 participants were categorized into the cognitive decline group. With regard to olfactory discrimination ability, we observed a significant difference between participants with and without cognitive decline based on the Japanese version of the Montreal Cognitive Assessment scores. Furthermore, we observed a significant positive correlation between the Japanese version of the the Montreal Cognitive Assessment scores and the Odor Stick Identification Test for the Japanese scores, although no significant correlation was observed between the Japanese version of the Mini-Mental State Examination and the Odor Stick Identification Test for the Japanese scores. [Conclusion] Olfactory identification ability may be useful to detect early-stage cognitive decline in community-dwelling older individuals.

Physical function and health-related quality of life of community-dwelling older adults with locomotive syndrome and pre-frailty.

[Purpose] To consider the effective rehabilitation approaches for locomotive syndrome (LS) and pre-frailty, we examined the characteristics of physical function and health-related quality of life (HRQoL) in community-dwelling older adults. [Participants and Methods] Eighty-three individuals (age 71.8 ± 5.5 years, 29 males and 54 females) were divided into robust (R), LS, and locomotive syndrome with pre-frailty (LSP) groups. We compared the subscale and summary scores of the 36-Item Short-Form Health Survey (SF-36) as HRQoL indices. The grip strength, five-chair stand up test (SS-5), and normal walking speed were the physical function indices. [Results] The LS group had lower two-step scores and normal walking speed but there was no significant difference in the SF-36. The two-step score and 25-question geriatric locomotive function scale, SS-5, seven SF-36 subscales, and mental component summary (MCS) scores were lower in the LSP group. Compared to that of the LS group, the LSP group did not show significant difference in physical function but showed lower values in overall health, vitality, mental health, and MCS in the SF-36 subscales. [Conclusion] The subjective evaluation of one's health was lower than that of the deterioration of physical function as a characteristic of the LSP.

An Experimental Feasibility Study Evaluating the Adequacy of a Sportswear-Type Wearable for Recording Exercise Intensity.

Sportswear-type wearables with integrated inertial sensors and electrocardiogram (ECG) electrodes have been commercially developed. We evaluated the feasibility of using a sportswear-type wearable with integrated inertial sensors and electrocardiogram (ECG) electrodes for evaluating exercise intensity within a controlled laboratory setting. Six male college athletes were asked to wear a sportswear-type wearable while performing a treadmill test that reached up to 20 km/h. The magnitude of the filtered tri-axial acceleration signal, recorded by the inertial sensor, was used to calculate the acceleration index. The R-R intervals of the ECG were used to determine heart rate; the external validity of the heart rate was then evaluated according to oxygen uptake, which is the gold standard for physiological exercise intensity. Single regression analysis between treadmill speed and the acceleration index in each participant showed that the slope of the regression line was significantly greater than zero with a high coefficient of determination (walking, 0.95; jogging, 0.96; running, 0.90). Another single regression analysis between heart rate and oxygen uptake showed that the slope of the regression line was significantly greater than zero, with a high coefficient of determination (0.96). Together, these results indicate that the sportswear-type wearable evaluated in this study is a feasible technology for evaluating physical and physiological exercise intensity across a wide range of physical activities and sport performances.

A Study of Changes of Physical Functions According to Changes in Cognitive Functions in Community-Dwelling Elderly People Who Participated in an Exercise Program.

Although it is known that physical function differs depending on the state of cognitive function, there are no studies that consider changes in cognitive functions when evaluating physical functions of participants before and after an exercise program. In this study, it was observed changes in cognitive function and physical functions of elderly people who participated in a community-based exercise program for 6 months, and examined changes in physical functions that took into account changes in cognitive functions. Forty-nine participants, whose cognitive and physical functions were both measured before and after the exercise program, were included in the analysis. The Japanese version of the Montreal Cognitive Assessment (MoCA-J) was used to assess participants' cognitive function and to determine whether they had mild cognitive impairment (MCI). To assess physical functions, a battery of physical tests was completed. Participants were classified into four groups (before/after; non-MCI/non-MCI, MCI/MCI, non-MCI/MCI, and MCI/non-MCI) according to the changes in cognitive functions after six months. There was no significant difference in the physical functions of the four groups before the start of the program. When changes in physical functions were examined in each group, some changes in physical functions were observed in the groups other than the non-MCI/MCI group. However, there was no significant difference in the physical functions between the four groups after the program. It was suggested that changes in physical functions of elderly people who participated in a community-based exercise program over a 6-month period were not different due to changes in cognitive functions.

Acute effects of moderate-intensity cycling exercise on endothelial function in young healthy men: An investigation using the reactive hyperemia index.

BACKGROUND: Endothelial cells play an important role in the prevention of cardiovascular disease. OBJECTIVE: In this study, we examined the effects of transient aerobic exercise on peripheral endothelial function. METHODS: Twenty-seven healthy male college students were selected as subjects and randomly divided into two groups: 13 in the control group and 14 in the exercise group. The subjects in the exercise group had a 15-minute supine rest, followed by 30 minutes of cycling exercise at moderate intensity, while measuring the reactive hyperemia index (RHI), an indicator of endothelial function, before and after exercise. The subjects in the control group had a 40-minute rest, during which RHI was measured with the same timing as in the exercise group. RESULTS: Two-factor analysis of variance revealed a statistically significant interaction effect. In the exercise group, RHI increased significantly after exercise. However, no significant change was observed in the control group. When RHI before exercise was compared between the two groups, no significant difference was found. However, RHI after exercise was significantly higher in the exercise group. CONCLUSIONS: The results of this study suggest that 30 minutes of moderate-intensity exercise may have a favorable impact on peripheral endothelial function.

Effects of exercise intervention on arterial stiffness in middle-aged and older females: evaluation by measuring brachial-ankle pulse wave velocity and cardio-ankle vascular index.

[Purpose] Brachial-ankle pulse wave velocity (baPWV) and cardio-ankle vascular index (CAVI) are simple, accurate, and reproducible indices of arterial stiffness. However, only a few studies have evaluated the influence of exercise-training baPWV and CAVI on arterial stiffness. Thus, this study aimed to examine the influence of aerobic-training baPWV and CAVI on arterial stiffness. [Participants and Methods] The participants were 20 middle-aged females (age, 60.1 ± 1.6 years) who were sedentary non-smokers. The participants underwent an exercise intervention, including a 50-min session of moderate-intensity exercises two or three times a week for 12 weeks. Blood pressure (BP), baPWV, and CAVI were measured before and after exercise. Blood nitrite/nitrate (NOx) was also measured as an index of vascular endothelial function. [Results] BaPWV significantly decreased after exercise, whereas CAVI and blood NOx did not change significantly after exercise. A significant correlation was observed between the decrease in baPWV and systolic BP after exercise. In addition, the participants with higher systolic BP before exercise showed a greater decrease in baPWV after exercise. [Conclusion] These results suggest that BP has a significant role in decreasing arterial stiffness after exercise. Further studies are required to elucidate the similarities and differences between baPWV and CAVI to use them more effectively as assessment parameters for arterial stiffness.

Cognitive function in middle-aged and older adults participating in synchronized swimming-exercise.

[Purpose] The purpose of the present study was to examine cognitive function in middle-aged and older adults regularly engaging in synchronized swimming-exercise. [Subjects and Methods] Twenty-three female synchronized swimmers ranging in age from 49 to 85 years were recruited for the present study. The duration of synchronized swimming experience ranged from 1 to 39 years. The control group consisted of 36 age- and gender-matched community-dwelling middle-aged and older adults (age range: 49 to 77 years). Cognitive function was evaluated using the Japanese version of the Montreal Cognitive Assessment (MoCA-J) and compared between the synchronized swimmers and control participants. [Results] No significant differences in mean total MoCA-J scores were observed between the synchronized swimmers and control participants (23.2 ± 3.1 and 22.2 ± 3.6, respectively). Twenty-nine subjects in the control group and 17 in the synchronized swimming group scored below 26 on the MoCA-J, indicative of mild cognitive impairment. Significant differences in delayed recall-but not in visuospatial/executive function, naming, attention, language, abstraction, or orientation-were also observed between the two groups. [Conclusion] The results of the present study suggest that synchronized swimming has beneficial effects on cognitive function, particularly with regard to recent memory.

Influence of detraining on temporal changes in arterial stiffness in endurance athletes: a prospective study.

[Purpose] We examined the effects of detraining on temporal changes in arterial stiffness in endurance athletes. [Subjects] Eighteen female university athletes requiring high endurance exercise capabilities were classified into 2 groups: 10 retired players (detraining group) and 8 active players (training group). [Methods] Brachial-ankle pulse wave velocity, an index of arterial stiffness, was measured a total of 6 times: immediately before retirement of the detraining group and at 1, 2, 3, 6, and 12 months after retirement. [Results] Brachial-ankle pulse wave velocity was measured in the training group at the same 6 points to allow comparison with the detraining group. The brachial-ankle pulse wave velocity in the detraining group increased significantly at 3 and 12 months as compared with that at 0 months and showed a significant increase at 12 months compared with that at 1 month. Moreover, the brachial-ankle pulse wave velocity in the detraining group was significantly higher at 3, 6, and 12 months than in the training group. [Conclusion] These results revealed that detraining may result in increased arterial stiffness from 3 months onward in endurance athletes.

Residual salivary secretion ability may be a useful marker for differential diagnosis in autoimmune diseases.

BACKGROUND: We have elucidated decreased resting salivary flow in approximately 60% of patients with autoimmune diseases not complicated by Sjögren syndrome (SjS). In this study, salivary stimulation tests using capsaicin were performed to examine residual salivary secretion ability in patients with autoimmune diseases. MATERIALS AND METHODS: Fifty-eight patients were divided into three groups: patients with primary or secondary SjS (SjS group), patients with systemic sclerosis not complicated by SjS (SSc group), and patients with other autoimmune diseases (non-SjS/non-SSc group). Simple filter paper and filter paper containing capsaicin were used to evaluate salivary flow rates. RESULTS: Resting salivary flow rates were significantly lower in the SjS and SSc groups than in the non-SjS/non-SSc group but did not differ significantly between the SjS and SSc groups. Capsaicin-stimulated salivary flow rates were significantly lower in the SjS and SSc groups than in the non-SjS/non-SSc group, but not significantly different between the SjS and SSc groups. In the non-SjS/non-SSc group, salivary flow rates increased after capsaicin stimulation to the threshold level for determination of salivary gland dysfunction, whereas no improvement was observed in the SjS and SSc groups. CONCLUSION: Residual salivary secretion ability may be a useful marker for differential diagnosis in autoimmune diseases.

A simple test for salivary gland function measuring resting and stimulated submandibular and sublingual secretions.

OBJECTIVE: This study examined the application of a simple screening test for salivary gland function by measuring resting and stimulated submandibular and sublingual secretions. STUDY DESIGN: An assay system was designed to use filter paper incorporating the chromophore of melanoidin or stimuli such as capsaicin and citric acid. We investigated the relationship between resting and stimulated secretions and melanoidin migration at 2 minutes for healthy and dry mouth groups. RESULTS: The healthy group showed a significant increase in the migration of melanoidin in the paper after citric acid or capsaicin stimulation. In contrast, patients with Sjögren syndrome showed no significant migration in spite of the stimulation. However, some participants with Sjögren syndrome or dry mouth showed a significant increase in the migration of melanoidin after stimulation. CONCLUSIONS: These results show that the newly developed method should be useful for evaluation of residual salivary gland function and screening for hyposalivation with dry mouth.

[Case of successful pregnancy and childbirth in a rheumatoid arthritis patient treated with etanercept].

The patient was a 34-year-old woman who, at age 23, was diagnosed with rheumatoid arthritis (RA) presenting with morning stiffness, swelling and tenderness of bilateral knee joints and metacarpophalangeal (MP) joints of the right second and third fingers, increased C-reactive protein (CRP) levels, and a high level of rheumatoid factor (RF). The patient was maintaining remission with oral dose of bucillamine (BUC; 300 mg/day); however, due to the deterioration of arthralgia at age 26, she was additionally administered 8 mg/week of methotrexate (MTX), which improved the symptoms. Thereafter, the prescription of BUC was discontinued. At age 31, she experienced onsets of swelling and tenderness in both the knee joints and wrists and in MP joints of the right second and third fingers; further, CRP levels increased to 5.44 mg/dL, resulting in increased RA activity. The concomitant administration of infliximab was started at a dose of 3 mg/kg, which helped achieve favorable RA control. At age 32, approximately 2 years before childbirth, the prescription of infliximab was changed to 25 mg/dose of etanercept administered twice a week because the patient wished to conceive. Remission was maintained even after the drug change; therefore, MTX was discontinued and the patient was treated with etanercept alone. After she was confirmed to be pregnant in March of the following year, administration of etanercept was continued for treating of RA even during pregnancy. During that time, RA was favorably controlled, and the patient gave birth to a baby boy weighing 3192 g in October of the same year. The Apgar score of the baby was favorable. This case is considered important because, to the best of our knowledge, this may be the first report of a planned pregnancy and childbirth in a patient under administration of a biological preparation.

Hyposalivation in autoimmune diseases.

We have investigated the prevalence of dry mouth among patients with autoimmune diseases other than Sjögren's syndrome. One hundred and forty-four patients, excluding patients with primary Sjögren's syndrome, were enrolled in this study. The volume of saliva secreted was measured with the screening technique for estimation of salivary flow, which uses a filter paper for diagnosing dry mouth. Disturbed salivary secretion was observed in 84 (58.3 %) of the 144 patients. In the case of patients free of Sjögren's syndrome, the prevalence of disturbed salivary secretion differed significantly among the disease groups (P < 0.05), with the prevalence being over 50 % in all disease groups other than the rheumatoid arthritis group and the highest in the systemic sclerosis group. There was significant positive correlation between the number of colored spots and oral visual analog scale score (r = 0.45, P < 0.0001). Autoimmune diseases can be accompanied by salivary gland dysfunction, regardless of the presence/absence of complication by Sjögren's syndrome. In the present study, the screening technique for estimation of salivary flow, which uses a filter paper for diagnosing dry mouth, was shown to be a useful means of detecting salivary gland dysfunction.

A case of fibromyalgia syndrome with anaphylaxis induced by intradermal injection of purified protein derivative.

When a 36-year-old woman with fibromyalgia syndrome (FMS) underwent the tuberculin test, urticaria developed on her trunk at 30 min after intradermal injection of purified protein derivative. Although the urticaria resolved, fever, facial edema, and generalized urticaria occurred after 8 h. A patient with FMS who developed a systemic allergic reaction after an intradermal skin test has not been reported. We should pay attention to anaphylactic reactions after intradermal injection in patients with FMS.

A screening test for capsaicin-stimulated salivary flow using filter paper: a study for diagnosis of hyposalivation with a complaint of dry mouth.

OBJECTIVE: The purpose of this study was to develop a simple screening technique for diagnosis of hyposalivation with dry mouth by estimation of capsaicin-stimulated salivary flow using filter paper. STUDY DESIGN: An assay system comprising 5 spots containing starch and potassium iodide on filter paper incorporating or without capsaicin and a coloring reagent was designed. We investigated whether the number of colored spots using the filter paper incorporating capsaicin could distinguish between healthy subjects and subjects with hyposalivation and dry mouth. RESULTS: In the healthy group (>200 µL/min; n = 33), the capsaicin-stimulated salivary flow significantly increased as compared with the resting salivary flow, from 1.2 ± 1.4 to 2.9 ± 1.3 colored spots (P < .05). In contrast, the hyposalivation group with dry mouth (<100 µL/min; n = 32) hardly changed (4.4 ± 1.0 vs 4.9 ± 0.2), except for 3 subjects who had considerable elevated secretion on capsaicin stimulation. CONCLUSION: By measuring resting and stimulated salivary flows, this method should be useful for evaluating retained functional ability of salivary glands and screening of hyposalivation with dry mouth.

Multiple symptoms of higher brain dysfunction caused by Marchiafava-Bignami disease in a patient with dermatomyositis.

A 65-year-old woman with dermatomyositis (DM) was admitted because of disorientation, mental dysfunction, and disturbance of consciousness. Prior to admission, she suffered from septic and hypovolemic shock. There was no evidence of active DM on physical examination and laboratory tests. Cerebrospinal fluid examination revealed no signs of meningitis. Because of clinical symptoms and findings on magnetic resonance images, such as the lesion in the splenium of the corpus callosum that was a low-intensity area on T1-weighted images and a high intensity on T2-weighted images; she was diagnosed as Marchiafava-Bignami disease (MBD). She received a combination of vitamin B, vitamin E, vitamin C, and nicotinic acid. Her symptoms improved gradually, and she was discharged at 1.5 months after admission. There has been no report of a case of DM with MBD. This report may provide useful data with regard to the mechanisms of central nervous system (CNS) disorders in patients with DM.

Portal vein thrombosis in a patient with hepatitis C virus-related cirrhosis complicated with antiphospholipid syndrome.

We report a rare case of portal vein thrombosis (PVT) associated with antiphospholipid syndrome (APS) and hepatitis C virus-related cirrhosis. A 59-year-old woman with hepatitis C virus (HCV) infection was admitted because of coma. The blood test showed a typically cirrhosis pattern including an elevated serum ammonia level. Abdominal computed tomography showed liver cirrhosis and thrombus in the right branch of the portal vein. To elucidate the cause of PVT, antiphospholipid antibodies were examined. Both IgG anti-cardiolipin antibody (ELISA) and IgG anti-cardiolipin-beta2 -glycoprotein I complex antibody (ELISA) were positive. When PVT is detected in a patient with cirrhosis, it might be necessary to examine antiphospholipid antibodies to clarify the cause of PVT.

A case of polymyositis with a significantly high level of KL-6 associated with pancreatic cancer.

A 53-year-old man was diagnosed with polymyositis (PM) in 1997 and treated with prednisolone. The subjective symptoms of pneumonitis were poor. However, the KL-6 values were elevated to 2230 IU/l in March 2001. Abdominal computer tomography findings revealed a pancreatic-tail tumor and multiple liver nodules, diagnosed as primary pancreatic adenocarcinoma with multiple liver metastasis. The stage of the pancreatic cancer was IV, and curative surgery of the tumor was not indicated. Chemotherapy and radiotherapy were administered for the liver metastasis. However, these therapies were ineffective against the tumors. The patient died on 12 September 2001. If a high level of KL-6 is found without the increasing activity of lung disease containing interstitial pneumonia in PM patients, examination for the internal malignancies including pancreatic cancer should be performed, although cases of PM with a significantly high level of KL-6 associated with pancreatic cancer are rare.