Relationship between Cognitive Function and Sway of Body in Standing Posture: A Cross-Sectional Study.

BACKGROUND: The influence of neurological or balance dysfunction on cognitive impairment has not been well studied. We compared the results of the balance test, measured by either head or foot sway to consider whole body sway, with those of the cognitive impairment test. METHODS: Individuals of either gender, aged over 60 years, underwent a 30 s balance test. We measured sway while standing on one-leg or two-legs. Sway was evaluated by the distance or area of movement of the head or foot pressure. We also evaluated the effect of visual condition: eyes-open (EO) or -closed (EC). The Mini-Mental State Examination (MMSE) was used to evaluate the degree of cognitive impairment. RESULTS: The head sway area standing on one leg was significantly correlated to MMSE score with EO (correlation r = -0.462). In standing on two legs, no sway test results showed a significant correlation to MMSE scores with EO. With EC, the magnitude of sway became greater, and was significantly correlated to MMSE scores in the head distance. CONCLUSION: Although the correlation between head sway and MMSE was not strong, head sway showed a stronger correlation than did foot pressure sway. Standing on one leg, as measured by head sway area, may thus predict cognitive impairment.

Association of home blood pressure with sleep and physical and mental activity, assessed via a wristwatch-type pulsimeter with accelerometer in adults.

This study aimed to examine the associations between home blood pressure (HBP) and sleep and activity assessed using data obtained via a wristwatch-type pulsimeter with accelerometer (Pulsense®) using original software. We recruited 28 elderlies and 40 employees aged 24-81 years who were not on hypotensive agents and sleeping drugs. Sleep, activity, and HBP were measured consecutively over a 5-7-day period. Body mass index (BMI), base heart rate (HR0), and age showed significant correlation with HBP in a simple and multiple linear regression analysis. HR0 was positively, and log deep sleep duration, negatively correlated with HBP in the adjusted multiple linear regression analysis. Physical and mental activities were negatively correlated with systolic blood pressure (SBP) in a simple linear regression, but high physical and mental activities tend to reduce deep sleep duration. Self-recorded sleep duration had no relationship with HBP. In conclusion, HR0, BMI, age, deep sleep duration, and activity showed relationships with HBP. Using this type of wristwatch and observing daily sleep and activity data with HBP measurement may have important clinical implication.

Influence of Acute Mental Arithmetic Stress on Taste and Pungency.

Mental stress is a known risk factor for disease. This study investigated changes in sensations of taste and pungency before and after mental stress. Thirty healthy male university students rested for 20 min, performed mental arithmetic tasks for 10 min, and then underwent measurement of changes in their taste and ability to discern pungency. Taste was measured with the "Taste Disk®," and pungency was measured by a filter-paper disc method using capsaicin solution. Subjects were not told the order of the reagent solutions used. To quantify pain sensation, a weak current applied to the central inner forearm skin by a Pain Vision® quantitative pain sensation analyzer was gradually increased. The degree of stress was measured by portable electrocardiography (ECG). During mental stress, the cognitive threshold of salty taste, sweet taste, and bitterness was significantly decreased, whereas the sensations of pungency and forearm skin pain were increased and showed significant correlation. Based on sympathetic nerve activity analyzed with the ECG, the subjects were divided into the mental stress group and non-mental stress group. The mental stress group experienced an increase in the pungency threshold and sensation of forearm skin pain with significantly high correlations obtained, whereas no correlation was found between these factors in the non-mental stress group. Acute mental stress increased the sensitivity to taste but decreased the sensitivity to the sensation of pungency on the tongue and pain on the skin. Sympathetic activity activated by stress may affect taste and the sensation of pungency.

Wearable and low-stress ambulatory blood pressure monitoring technology for hypertension diagnosis.

We propose a highly wearable, upper-arm type, oscillometric-based blood pressure monitoring technology with low-stress. The low-stress is realized by new developments in the hardware and software design. In the hardware design, conventional armband; cuff, is almost halved in volume thanks to a flexible plastic core and a liquid bag which enhances the fitness and pressure uniformity over the arm. Reduced air bag volume enables smaller motor pump size and battery leading to a thinner, more compact and more wearable unified device. In the software design, a new prediction algorithm enabled to apply less stress (and less pain) on arm of the patient. Proof-of-concept experiments on volunteers show a high accuracy on both technologies. This paper mainly introduces hardware developments. The system is promising for less-painful and less-stressful 24-hour blood pressure monitoring in hypertension managements and related healthcare solutions.

Lifestyle monitoring with the use of an earphone-type thermometer, an ambulatory blood pressure monitoring and a new wristwatch-type pulsimeter with accelerometer.

We investigated the relationship among 24-h blood pressure (BP), pulse rate (PR) and core temperature by using an ambulatory BP monitoring, a new wristwatch-type pulsimeter with accelerometer (WPA) and an ear thermometer simultaneously. Our results suggest that the ear temperature which reflects the core body temperature was lowest at base PR during sleep and 75% of normotensives and 54% of subjects without hypertensive medication had a significant correlation between BP and PR. Diabetic subjects showed a significantly higher PR during sleep than non-diabetic subjects. Three types of equipments, especially a new WPA, are expected to be useful for daily lifestyle monitoring to evaluate risk of complications of hypertension and diabetes.

The overnight effect of dietary energy balance on postprandial plasma free amino acid (PFAA) profiles in Japanese adult men.

The plasma free amino acid (PFAA) profile is affected by various nutritional conditions, such as the dietary energy balance. Regarding the clinical use of PFAA profiling, it is of concern that differences in food ingestion patterns may generate systematic errors in a plasma amino acid profile and constitute a confounding factor in assessment. In this study, the overnight impact of the dietary energy balance on the postprandial plasma amino acid profile was investigated to elucidate in particular the effects of high protein meals typical in Japanese cuisine. We conducted diet-controlled, crossover trials in eleven healthy male volunteers aged 40-61 y. They consumed either a normal meal (meal N) or high protein meal (meal H) at dinner. Forearm venous blood was collected, and plasma amino acid concentrations were measured before dinner and the next morning. We found that a high protein meal in the evening that contained 40% energy would significantly increase the PFAA concentration the next morning, even more than 12 hours after the meal. Among amino acids, the most significant difference was observed in the branched-chain amino acids (BCAAs) and in some urea-cycle related compounds. If the subject consumed the high protein diet at dinner, the PFAA profile after overnight fasting might be still affected by the meal even 12 hours after the meal, suggesting that the PFAA profile does not reflect the subject's health condition, but rather the acute effect of high protein ingestion.

The significance and robustness of a plasma free amino acid (PFAA) profile-based multiplex function for detecting lung cancer.

BACKGROUND: We have recently reported on the changes in plasma free amino acid (PFAA) profiles in lung cancer patients and the efficacy of a PFAA-based, multivariate discrimination index for the early detection of lung cancer. In this study, we aimed to verify the usefulness and robustness of PFAA profiling for detecting lung cancer using new test samples. METHODS: Plasma samples were collected from 171 lung cancer patients and 3849 controls without apparent cancer. PFAA levels were measured by high-performance liquid chromatography (HPLC)-electrospray ionization (ESI)-mass spectrometry (MS). RESULTS: High reproducibility was observed for both the change in the PFAA profiles in the lung cancer patients and the discriminating performance for lung cancer patients compared to previously reported results. Furthermore, multivariate discriminating functions obtained in previous studies clearly distinguished the lung cancer patients from the controls based on the area under the receiver-operator characteristics curve (AUC of ROC = 0.731 ~ 0.806), strongly suggesting the robustness of the methodology for clinical use. Moreover, the results suggested that the combinatorial use of this classifier and tumor markers improves the clinical performance of tumor markers. CONCLUSIONS: These findings suggest that PFAA profiling, which involves a relatively simple plasma assay and imposes a low physical burden on subjects, has great potential for improving early detection of lung cancer.

Accuracy of the pulse delay time technique with triple cuff for objective indirect blood pressure measurement.

OBJECTIVE: We developed a new technique to measure blood pressure (BP) - the triple cuff and pulse delay time technique (TC-PDT) - which measures delay time with a single sensor at a single site unlike the existing delay time methods. This study aimed to evaluate the adequacy and accuracy of TC-PDT. METHODS: TC-PDT measures delay time, which represents the difference in the arrival time of the arterial pulse wave between the proximal and distal areas of the cuff and provides clear criteria for BP determination based on the mechanism. Adequacy of delay time in TC-PDT was confirmed in comparison with established delay time of the pulse transit time technique (PTT). TC-PDT accuracy was evaluated according to the standard guidelines. RESULTS: In TC-PDT, delay time showed changes in parallel with those observed in PTT. The correlation coefficient between BP by TC-PDT and that by PTT was 0.98 (P < 0.01) for SBP and 0.93 (P < 0.01) for DBP. According to the International Protocol guidelines (2002), the BP measurements of 33 patients met the recommended values for phase 1, 2.1 and 2.2 measurements. As per the Association for the Advancement of Medical Instrumentation (AAMI) SP10 guidelines (2002), the mean difference in BP measured by TC-PDT and that measured by the auscultatory technique in 85 patients was 1.0 ± 5.1 mmHg for SBP and -0.4 ± 4.5 mmHg for DBP, which conformed to the requirements. CONCLUSION: TC-PDT is adequate to measure delay time and provides adequate and accurate measurements of BP. This device has the potential to be a standard tool for indirect BP measurement.

Relationship of ambulatory blood pressure and the heart rate profile with renal function parameters in hypertensive patients with chronic kidney disease.

Strict blood pressure (BP) control is reportedly important for the management of hypertensive patients with chronic kidney disease (CKD). The purpose of this cross-sectional study was to examine whether the variables of ambulatory BP and the heart rate (HR) profile, central hemodynamics, and arterial stiffness were closely related to the renal function parameters (urine albumin excretion rate [UACR] and estimated glomerular filtration rate [eGFR]) observed in 25 consecutive hospitalized hypertensive patients with CKD. There were significant positive relationships between UACR and 24-hour, daytime, and nighttime ambulatory systolic BP. In addition, there were significant negative relationships between UACR and 24-hour and daytime HR variability. The circulating B-type natriuretic peptide level and hemoglobin A1c were also positively related to UACR. With respect to eGFR, although the 24-hour and nighttime HR variability were positively associated with eGFR, the circulating pentosidine and nighttime HR had a negative relationship with eGFR. On the other hand, central hemodynamics and arterial stiffness did not exhibit any significant association with renal function parameters. These results indicate that ambulatory BP and the HR profile are closely modulated by renal function deterioration. Further studies are needed to investigate the causal relationship between ambulatory BP and the HR profile and renal function parameters in hypertensive patients with CKD.

Combination therapy of angiotensin II receptor blocker and calcium channel blocker exerts pleiotropic therapeutic effects in addition to blood pressure lowering: amlodipine and candesartan trial in Yokohama (ACTY).

Recent guidelines recommend combination antihypertensive therapy to achieve the target blood pressure (BP) and to suppress target organ damage. This study aimed to examine the beneficial effects of combination therapy with candesartan and amlodipine on BP control and markers of target organ function in Japanese essential hypertensive patients (N = 20) who did not achieve the target BP level during the monotherapy period with either candesartan or amlodipine. After the monotherapy period, for patients already being treated with amlodipine, a once-daily 8 mg dose of candesartan was added on during the combination therapy period (angiotensin II receptor blocker [ARB] add-on group, N = 10), and a once-daily 5 mg dose of amlodipine was added on for those already being treated with candesartan (calcium channel blocker [CCB] add-on group, N = 10). Combination therapy with candesartan and amlodipine for 12 weeks significantly decreased clinic and home systolic blood pressure (SBP) and diastolic blood pressure (DBP). In addition, the combination therapy was able to significantly reduce urine albumin excretion without decrease in estimated glomerular filtration ratio and resulted in significant improvements in brachial-ankle pulse wave velocity, central SBP, and insulin sensitivity. Furthermore, the CCB add-on group showed a significantly greater decrease in clinic and home DBP than the ARB add-on group. The calcium channel blocker add-on group also exhibited better improvements in vascular functional parameters than the ARB add-on group. These results suggest that combination therapy with candesartan and amlodipine is an efficient therapeutic strategy for hypertension with pleiotropic benefits.

Tailor-made preventive medicine integrating amino acid checkup and its application toward disaster-stricken areas.

ICT technologies for healthcare are useful in myriad locations for people with lifestyle-related illnesses and health irregularities. When symptoms turn into actual illnesses, it is difficult for them to be managed, and this situation is relevant for managing the health of victims after large-scale disasters; it is important to keep people healthy to prevent them from acquiring illness. This paper proposes a system of personalized preventive medicine for individuals to maintain their health and receive evidence-based feedback. We introduce general medical checkups, ubiquitous sensing, and plasma amino acid analysis as the system's core components. We evaluate these elements and discuss their applicability toward the disaster-stricken Tohoku area of Japan. This is an initial evaluation, but some functions are being used in the area. There are gaps between research results and actually deployable technologies, but it is important to use and improve the quality of life of victims who are ultimately forced to live in temporary housing for more than five years.

Weight gain and risk of impaired fasting glucose after smoking cessation.

BACKGROUND: Observation of early changes in fasting plasma glucose level induced by post-smoking cessation weight gain is useful in predicting the risks of diabetes mellitus (DM) and impaired fasting glucose (IFG). We investigated the effect of post-smoking cessation weight gain on early changes in the risk of a high fasting plasma glucose (IFG) level (≥100 mg/dL). METHODS: In 946 subjects who underwent repeated health examinations after smoking cessation, changes in body mass index (BMI) and the odds ratio (OR) for IFG risk (adjusted for sex, age, BMI, fasting plasma glucose at year 1, and alcohol consumption) were calculated every year for 3 years after smoking cessation. RESULTS: After smoking cessation, the rate of BMI increase significantly increased in quitters: 2.36% at year 2 (never smokers: 0.22%, current smokers: 0.39%) and 0.46% at year 3 (never smokers: 0.14%, current smokers: 0.32%). However, it decreased by 0.15% at year 4 (never smokers: 0.12%, current smokers: 0.26%). The ORs for quitters did not significantly increase at any time during the follow-up period. However, among quitters who had smoked at least 20 cigarettes per day, it was significantly higher (OR 1.51, 95% confidence interval 1.1-2.01 at year 1 and 1.71, 1.23-2.38 at year 2). CONCLUSIONS: The time course of the risk of IFG after smoking cessation was similar to that for the rate of BMI increase. In contrast to the findings of previous reports, the increase in IFG risk after smoking cessation was brief and disappeared in the absence of a significant increase in BMI.

Plasma free amino acid profiling of five types of cancer patients and its application for early detection.

BACKGROUND: Recently, rapid advances have been made in metabolomics-based, easy-to-use early cancer detection methods using blood samples. Among metabolites, profiling of plasma free amino acids (PFAAs) is a promising approach because PFAAs link all organ systems and have important roles in metabolism. Furthermore, PFAA profiles are known to be influenced by specific diseases, including cancers. Therefore, the purpose of the present study was to determine the characteristics of the PFAA profiles in cancer patients and the possibility of using this information for early detection. METHODS AND FINDINGS: Plasma samples were collected from approximately 200 patients from multiple institutes, each diagnosed with one of the following five types of cancer: lung, gastric, colorectal, breast, or prostate cancer. Patients were compared to gender- and age- matched controls also used in this study. The PFAA levels were measured using high-performance liquid chromatography (HPLC)-electrospray ionization (ESI)-mass spectrometry (MS). Univariate analysis revealed significant differences in the PFAA profiles between the controls and the patients with any of the five types of cancer listed above, even those with asymptomatic early-stage disease. Furthermore, multivariate analysis clearly discriminated the cancer patients from the controls in terms of the area under the receiver-operator characteristics curve (AUC of ROC >0.75 for each cancer), regardless of cancer stage. Because this study was designed as case-control study, further investigations, including model construction and validation using cohorts with larger sample sizes, are necessary to determine the usefulness of PFAA profiling. CONCLUSIONS: These findings suggest that PFAA profiling has great potential for improving cancer screening and diagnosis and understanding disease pathogenesis. PFAA profiles can also be used to determine various disease diagnoses from a single blood sample, which involves a relatively simple plasma assay and imposes a lower physical burden on subjects when compared to existing screening methods.

Effect of salt reduction intervention program using an electronic salt sensor and cellular phone on blood pressure among hypertensive workers.

We investigated the effectiveness of a workplace intervention program that utilized self-monitoring of daily salt excretion by an electronic salt sensor and sent personalized e-mail advice via cellular phone. Forty-one hypertensive male workers were assigned to intervention and control groups, then counseled together. Intervention group members were asked to measure daily salt excretion and received e-mail advice. After 4 weeks, a greater decrease of blood pressure (BP) was observed in the intervention group, with significant reductions to daily salt excretion and home BP. The new intervention program is considered useful for BP control among hypertensive workers.

Interoperable and diligent body area networks over IEEE802.15.6 for real-time monitoring.

Currently, there are no standardization efforts to define interfaces and verify interoperability among implementations for body area networks (BANs) on IEEE802.15.6. A BAN consists of small and lightweight sensors, such as the ring-type SpO2 sensor, and a coordinator that collects vital data from the sensors and transfers them to a backend system for real-time monitoring and analysis. It is important for sensors to be easy-to-use, light for wearing and that they are long-lived using a small rechargeable battery. IEEE802.15.6 provides basic features for these sensors. We establish an industry-driven standardization association for healthcare/medical services on IEEE802.15.6. Industry standardization targets current and emerging small sensors, not those for fixed medical devices in hospitals, such as those in the ISO/IEEE11073 family, and deals with time-driven data. We propose a combination of various layers of power-saving functions for a sensor that satisfies the interfaces. We discuss these functions and evaluate them. As a feasibility study, we then test a false-alert system using a BAN configuration following the standard interfaces, though the standardizations and evaluations are still in progress along with the IEEE802.15.6 standardization activity.

Lifestyle modification in metabolic syndrome and associated changes in plasma amino acid profiles.

BACKGROUND: Although lifestyle modification is the key treatment of metabolic syndrome (MetS), clinical data on the dynamical relationship between metabolic state and MetS has been limited. This study investigated the mutual correlations between demographic and biochemical variables, and the metabolic state based on the plasma amino acid (AA) concentrations, during a lifestyle modification for MetS. METHODS AND RESULTS: Japanese subjects, consisting of 54 patients with MetS [MetS(+)] and 35 persons without MetS [MetS(-)] were included in the study. Before a lifestyle modification program, the levels of glutamate metabolism-related AA (Glu-mAA), aromatic AA metabolism-related AA (Aromatic-mAA) and alanine metabolism-related AA (Ala-mAA) were significantly higher, while those of glycine-serine-threonine metabolism-related AA (Gly-Ser-Thr-mAA) were significantly lower compared to those in MetS(-). After a lifestyle modification, significant reductions (P<0.05) in the BMI (-1.4 kg/m(2)), mean blood pressure (-7.9 mmHg), hemoglobin A(1c) (-0.4%), and triglycerides (-30.6 mg/dl) were observed, and significant differences in the plasma AA levels between MetS(+) and MetS(-) were resolved. In addition, the diagnostic items of MetS were positively correlated with the levels of Glu-mAA, Ala-mAA, branched chain AA (BCAA)-mAA, Aromatic-mAA, and negatively correlated with the levels of Gly-Ser-Thr-mAA. CONCLUSIONS: As MetS subsided, the abnormality of mean plasma AA levels of the MetS(+) group returned to similar values as those in the MetS(-) group, suggesting a novel viewpoint regarding the metabolic mechanism of lifestyle modification.

The blood pressure lowering effect of lactotripeptides and salt intake in 24-h ambulatory blood pressure measurements.

It is well known that the sour milk containing lactotripeptides has a blood pressure lowering effect. The aim of this study was to evaluate the blood pressure (BP) lowering effect of lactotripeptides by monitoring home blood pressure, 24-h ambulatory measurements (ABPM), and daily urinary salt excretion. A total of 30 volunteers were given 200 ml of sour milk twice a day for 8 weeks after a 1-week run-in period. This preparation contained the lactotripeptides valine-proline-proline 2.66 mg and isoleucine-proline-proline 1.38 mg. The study participants had daily measurements of urinary salt excretion determined by an electric salt sensor and home blood pressure for each week during the run-in period, before the 4-and 8-week time points. 24-h ABPM was measured at the end of each week. Mean systolic blood pressure (SBP) during night sleep including base BP at 4 and 8 weeks were significantly lower than baseline values. Mean SBP and diastolic blood pressure (DBP) during night sleep of the 22 participants who belonged to the criteria of hypertension by 24-h ABPM was significantly decreased at 4 and 8 weeks. The change in 24-h mean SBP significantly correlated with mean urinary salt excretion over the three measurement periods. The 22 hypertensive subjects without taking lactotripeptides did not show significant change of blood pressure during 24 hours at 4 and 8 weeks. Our study confirmed the BP lowering effect of lactotripeptides during night-time sleep and showed that a lower intake of salt may increase the BP lowering effect of lactotripeptides through 24 hours in hypertensive subjects.

Effects of angiotensin II receptor blockers on the relationships between ambulatory blood pressure and anti-hypertensive effects, autonomic function, and health-related quality of life.

The aim of the present study was to examine the relationships between the anti-hypertensive effects, autonomic function, and health-related quality of life (HRQOL) following treatment of hypertensive subjects with angiotensin receptor blockers (ARBs) in hypertensives. Nineteen patients with hypertension were assigned randomly to daily treatment with ARBs. After 16 weeks of treatment, blood pressure (BP) and 24 h the ratio of low frequency to high frequency component (LF/HF), an index of sympathovagal balance were decreased by ARBs. The HRQOL scores improved during the study. In this study, ARB therapy was associated with an improvement in BP, autonomic function, and HRQOL.

Factors related to elevated 24-h blood pressure in young adults.

Variation in 24-h blood pressure (BP) is associated with multiple factors, but the association has not been thoroughly examined in young adults. To elucidate the potential factors associated with variation in 24-h BP, 331 healthy medical students were investigated. Awake mean BP negatively correlated with sleep duration in males. Sixty-seven subjects (20.2%) had a high 24-h BP according to the ESH/ESC 2007 guidelines (systolic blood pressure (SBP) 125 and/or diastolic blood pressure (DBP) 80 mmHg). After multivariate analysis for confounding factors, male gender, body mass index (BMI), smoking, the 24-h low/high frequency component (heart rate variability spectral analysis), and short sleep (5 h or less) were found to be associated with high BP. The present study is the first to demonstrate the multivariate risk factors for elevated 24-h BP in a large number of young adults. Further investigation is required to determine the causal relationship between modifiable BP-related factors and elevated 24-h BP in young adults.

Low-power secure body area network for vital sensors toward IEEE802.15.6.

Many healthcare/medical services have started using personal area networks, such as Bluetooth and ZigBee; these networks consist of various types of vital sensors. These works focus on generalized functions for sensor networks that expect enough battery capacity and low-power CPU/RF (Radio Frequency) modules, but less attention to easy-to-use privacy protection. In this paper, we propose a commercially-deployable secure body area network (S-BAN) with reduced computational burden on a real sensor that has limited RAM/ROM sizes and CPU/RF power consumption under a light-weight battery. Our proposed S-BAN provides vital data ordering among sensors that are involved in an S-BAN and also provides low-power networking with zero-administration security by automatic private key generation. We design and implement the power-efficient media access control (MAC) with resource-constraint security in sensors. Then, we evaluate the power efficiency of the S-BAN consisting of small sensors, such as an accessory type ECG and ring-type SpO2. The evaluation of power efficiency of the S-BAN using real sensors convinces us in deploying S-BAN and will also help us in providing feedbacks to the IEEE802.15.6 MAC, which will be the standard for BANs.