Environmental factors and physical activity among youth in rural Japan: a 1-year prospective study

Background

Although moderate-to-vigorous physical activity (MVPA) has multiple health benefits, current global activity levels among children are quite low. Environmental influences on MVPA levels among children and adolescents in rural areas are unclear. The present study examined if environmental factors were associated with MVPA in children and adolescents in rural Japan.

Methods

Two school-based serial surveys were conducted in 2017 and 2018 for 1,461 children and adolescents (10-14 years old) in Unnan City, Japan. If meeting the WHO recommended MVPA levels: at least 60 minutes/day was assessed via the Japanese translation of the WHO Health Behaviour in School-aged Children survey questionnaire. Environmental factors, namely habitable land area, population size, and population density were calculated for each individuals' residential town, and categorized into three levels (small, medium, and large). Logistic regression was used to determine odds ratios (OR) and 95% confidence intervals (CI) of engaging in the recommended level of MVPA after 1 year by each environmental factor, adjusting for sex, school grades, body mass index, screen time, preference for PA, and MVPA level at baseline.

Results

Only 22.4% of children and adolescents were engaging in the recommended MVPA levels in 2018. Engaging in the recommended level of MVPA after 1 year was significantly associated with medium (OR = 1.63; 95%CI, 1.08-2.46) and large (OR = 1.69; 95%CI, 1.15-2.47) compared to small habitable areas, and with medium (OR = 1.01; 95%CI, 0.61-1.67) and large (OR = 1.75; 95%CI, 1.09-2.81) compared to small population size. Population density was not associated with MVPA.

Conclusions

This prospective study found that habitable area and population size were positively associated with MVPA at 1-year follow-up in rural Japan. In rural areas, habitable land areas and population size itself may be a better predictor for MVPA among children than population density.

Key messages

Habitable area and population size was positively associated with physical activity among children and adolescents in rural Japan. Population density as an environmental factor was not associated with physical activity.

Daytime Dynamo Electrodynamics With Spiral Currents Driven by Strong Winds Revealed by Vapor Trails and Sounding Rocket Probes

We investigate the forces and atmosphere-ionosphere coupling that create atmospheric dynamo currents using two rockets launched nearly simultaneously on 4 July 2013 from Wallops Island (USA), during daytime Sq conditions with ΔH of -30 nT. One rocket released a vapor trail observed from an airplane which showed peak velocities of >160 m/s near 108 km and turbulence coincident with strong unstable shear. Electric and magnetic fields and plasma density were measured on a second rocket. The current density peaked near 110 km exhibiting a spiral pattern with altitude that mirrored that of the winds, suggesting the dynamo is driven by tidal forcing. Such stratified currents are obscured in integrated ground measurements. Large electric fields produced a current opposite to that driven by the wind, believed created to minimize the current divergence. Using the observations, we solve the dynamo equation versus altitude, providing a new perspective on the complex nature of the atmospheric dynamo.

Influence of an SGLT2 inhibitor, tofogliflozin, on the resting heart rate in relation to adipose tissue insulin resistance

AIMS

To examine the effects of a sodium-glucose co-transporter 2 (SGLT2) inhibitor, tofogliflozin, on resting heart rate by exploring baseline factors that independently influenced changes in the resting heart rate.

METHODS

Data on 419 participants in tofogliflozin phase 2/3 trials were analysed. Changes in resting heart rate from baseline to week 24 were analysed using an analysis of covariance (ANCOVA) model with groups (tofogliflozin/placebo) as a fixed effect and baseline values as covariates. The antilipolytic effect was evaluated as adipose tissue insulin resistance (Adipo-IR) and was calculated as the product of fasting insulin and free fatty acid. Multivariate analysis evaluated independent factors for changes in resting heart rate from baseline to week 24.

RESULTS

Of the participants, 58% were men, and mean age, HbA_1c , BMI and resting heart rate were 57.6 years, 65 mmol/mol (8.1%), 25.5 kg/m² and 66 bpm, respectively. At week 24, adjusted mean difference vs. placebo in the change from baseline was -2.3 bpm [95% confidence interval (CI) -4.6, -0.1] with tofogliflozin. Changes in resting heart rate were positively correlated with changes in Adipo-IR, whereas reductions in HbA_1c , body weight and blood pressure were similar independent of changes in resting heart among quartiles of resting heart rate change. On multivariate analysis, higher baseline resting heart rates and Adipo-IR values were significantly associated with greater reductions in resting heart rate.

CONCLUSIONS

Tofogliflozin corrected resting heart rate levels in accordance with baseline levels. Correction of high resting heart rates may be attributed to improved adipose tissue insulin resistance, leading to correction of hyperinsulinaemia.

Accelerometer-Determined Intensity and Duration of Habitual Physical Activity and Walking Performance in Well-Functioning Middle-Aged and Older Women: A Cross-Sectional Study

BACKGROUND

The association of physical activity (PA) intensities and duration spent in those activities with different walking tasks remains unclear.

OBJECTIVES

To examine the association between the duration of PA intensities and three walking speeds (usual walking speed, maximal walking speed and zig-zag walking speed).

DESIGN

Multiple linear regression analysis was used to estimate the association of age, BMI, maximum knee extension strength, light PA, moderate PA and vigorous PA with walking speeds.

SETTING

University lab.

PARTICIPANTS

Eighty-six older women (67 ± 7 years).

MEASUREMENTS

PA was measured for 30 consecutive days using the Lifecorder-EX accelerometer. Exercise intensity was categorized as light (levels 1-3), moderate (levels 4-6) and vigorous (levels 7-9) based on the manufacturer algorithms. Usual straight walking speed (20 m), maximal straight walking speed (20 m) and zig-zag walking speed tests (10 m) were performed by each participant.

RESULTS

For the usual straight walking speed model (R2 = 0.296, SEE = 0.15 m/s), the significant predictors were BMI, knee extension strength, light PA and vigorous PA. For the maximal straight walking speed model (R2 = 0.326, SEE = 0.20 m/s), only age was a significant predictor. For the zig-zag walking speed model (R2=0.417, SEE = 0.14 m/s), age and maximum knee strength were significant predictors in the model.

CONCLUSIONS

Overall, the results of this study suggest that vigorous PA and maximal knee extension strength are two important factors that are associated with different walking speeds in older women.

Gastrectomy with or without omentectomy for cT3–4 gastric cancer: a multicentre cohort study

Background

Omentectomy is performed widely for locally advanced gastric cancer to prevent disease recurrence. However, its clinical benefit is unknown.

Methods

This retrospective cohort study compared the outcome of gastrectomy with preservation of the omentum (GPO) and gastrectomy with resection of the omentum (GRO) among patients with cT3–T4 gastric cancer who underwent gastrectomy between 2006 and 2012 in one of five participating institutions. A consensus conference identified 28 variables potentially associated with outcome after gastrectomy for the estimation of propensity scores, and propensity score matching (PSM) was undertaken to control for possible confounders. Postoperative surgical outcomes, overall survival and disease recurrence were compared between GPO and GRO.

Results

A total of 1758 patients were identified, of whom 526 remained after PSM, 263 in each group. Median follow-up was 4·9 (i.q.r. 3·1–5·9) years in the GRO group and 5·0 (2·5–6·8) years in the GPO group. The incidence of postoperative complications of Clavien–Dindo grade III or more was significantly higher in the GRO group (17·5 versus 10·3 per cent; P = 0·016). Five-year overall survival rates were 77·1 per cent in the GRO group and 79·4 per cent in the GPO group (P = 0·749). There were no significant differences in recurrence rate or pattern of recurrence between the groups.

Conclusion

Overall survival and disease recurrence were comparable in patients with cT3–4 gastric cancer who underwent GPO or GRO.

Baicalin inhibits root resorption during tooth movement in a rodent model

OBJECTIVE

Baicalin mediates bone metabolism and has shown protective activity against periodontal tissue damage in a rat model of periodontitis. Therefore, we hypothesized that baicalin may inhibit the root resorption that occurs during orthodontic tooth movement and examined its effect on the histological changes in periodontal tissue that occur during tooth movement.

METHODS

First molars of rats were subjected to traction using excessive orthodontic force to produce a root resorption model. Rats in the baicalin group received baicalin for 3 weeks during tooth movement, and the amount of first molar movement on day 21 after the initiation of traction was measured by three-dimensional micro-computed tomography analysis. After tooth movement, tissue samples from the mesial and tension sides were collected, and successive horizontal sections were prepared and examined using hematoxylin-eosin and tartrate-resistant acid phosphatase (TRAP) staining and immunohistochemical staining for the receptor activator of NF-kB ligand (RANKL) and osteoprotegerin (OPG). The severity of root resorption was also determined by histological analysis.

RESULTS

There was no significant intergroup difference in tooth movement during the experimental exaggerated tooth movement. In comparison with the control group, the baicalin-treated group showed increased OPG expression, suppressed RANKL expression, and significantly fewer TRAP-positive cells in the first molars. The root resorption area was significantly smaller in the baicalin group.

CONCLUSIONS

Treatment with baicalin prevented root resorption without preventing tooth movement. Baicalin may be useful for the management of root resorption during orthodontic treatment.

Impact of Fat-Free Adipose Tissue on the Prevalence of Low Muscle Mass Estimated Using Calf Circumference in Middle-Aged and Older Adults

Previous studies proposed calf circumference cutoff values for predicting dual-energy X-ray absorptiometry (DXA)-derived low muscle mass. However, DXA-derived appendicular lean mass (aLM) includes non-skeletal muscle components such as the appendicular fat-free component of adipose tissue fat cells (aFFAT). The purpose of this study was to compare the calf circumference method of classification before (Model #1) and after (Model #2) eliminating the influence of FFAT in healthy Japanese adults (50 to 79 years; mean age 70 (SD 7) years). Model 1, and Model 2 for classifying low muscle mass had a sensitivity of 78% and 64%, specificity of 76% and 75%, positive predictive value of 31% and 28%, and negative predictive value of 96% and 93%, respectively. Appendicular fat-free component of adipose tissue has the potential to influence the ability of calf circumference to accurately classify individuals with low muscle mass. Consideration should be made when using this as a screening tool for low muscle mass.

Examination of the Effect of the Combined Use of Nd: YAG Laser Irradiation and Mechanical Force Loading on Bone Metabolism Using Cultured Human Osteoblasts

Introduction: In recent years, laser irradiation in the near-infrared ray (NIR) area has been reported to promote bone healing. There are also reports that laser irradiation accelerates orthodontic tooth movement. In this study, we investigated the effect of NIR laser irradiation and mechanical stimulation on osteoblasts. Methods: We seeded osteoblast-like cells and laser irradiation was performed 24 hours after cell seeding. In addition, a control group not receiving anything, a group receiving only Nd: YAG (neodymium-doped yttrium aluminum garnet) laser irradiation, a group receiving only centrifugal loading, and a group receiving both Nd: YAG laser irradiation and centrifugal force loading were set, and after 24 hours and after 48 hours, cells were collected and quantitative real-time polymerase chain reaction (PCR) was performed. Results: 24 hours after laser irradiation, the gene expression of alkaline phosphatase (ALP), the receptor activator of NF-κB ligand (RANKL) and osteoprotegerin (OPG) was significantly higher in the 2.0 W group than in the control group. In addition, the RANKL/OPG ratio was higher in the 2.0 W group than in the control group. Also, in the group using laser irradiation and centrifugal loading in combination, 24 hours after laser irradiation, ALP and OPG showed significantly higher values than those in the centrifugal load only group. Furthermore, the RANKL/OPG ratio also showed high values. Conclusion: These results suggest that osteoblast-like cells activate genes related to bone metabolism by combining mechanical stimulation and laser irradiation. This helps to elucidate the influence of laser irradiation during tooth movement.

Outcome of maintenance systemic chemotherapy with drug-free interval for metastatic urothelial carcinoma

OBJECTIVE

Aiming to achieve long-term disease control, maintenance systemic chemotherapy (MSC) with a 1-3-month drug-free interval is continued in selected patients. We report our experience of MSC for metastatic urothelial carcinoma (UC).

METHODS

Of 228 metastatic UC patients treated with systemic chemotherapy, 40 (17.5%, 40/228) had continuously undergone MSC. Data on the regimen, cycle number, and reason for the discontinuation of MSC were also collected. We analyzed OS from the initiation of MSC until death or the last follow-up, using the log-rank test to assess the significance of differences.

RESULTS

The median number of cycles of chemotherapy was 6, and the responses were CR in 6, PR in 20, SD in 13, and PD in 1 before MSC. Gemcitabine plus CDDP or carboplatin was mainly performed as MSC (70%, 28/40). MSC was repeated quarterly in 30 (75%, 30/40), every two months in 8 (20%, 8/40), and with other intervals in 2 (5%, 2/40). Overall, a median of 3.5 cycles (range: 1-29) of MSC was performed. The reason for the discontinuation of MSC was PD in 24 (60%, 24/40), favorable disease control in 9 (22.5%, 9/40), and myelosuppression in 3 (7.5%, 3/40), and for other reasons in 2 (5%, 2/40). MSC was ongoing in 2 (5%, 2/40). The median OS was 27 months from the initiation of MSC. PS0 (P = 0.0169), the absence of lung metastasis (P = 0.0387), and resection of the primary site (P = 0.0495) were associated with long-term survival after MSC.

CONCLUSIONS

In selected patients, long-term systemic chemotherapy could be performed with a drug-free interval. Our maintenance strategy with cytotoxic drugs may become one of the treatment options for long-term disease control.

Underlying Structure of Collective Bands and Self-Organization in Quantum Systems

The underlying structure of low-lying collective bands of atomic nuclei is discussed from a novel perspective on the interplay between single-particle and collective degrees of freedom, by utilizing state-of-the-art configuration interaction calculations on heavy nuclei. Besides the multipole components of the nucleon-nucleon interaction that drive collective modes forming those bands, the monopole component is shown to control the resistance against such modes. The calculated structure of ^{154}Sm corresponds to the coexistence between prolate and triaxial shapes, while that of ^{166}Er exhibits a deformed shape with a strong triaxial instability. Both findings differ from traditional views based on β/γ vibrations. The formation of collective bands is shown to be facilitated from a self-organization mechanism.

Effects of Human Full-length Amelogenin and C-terminal Amelogenin Peptide on the Proliferation of Human Mesenchymal Stem Cells Derived from Adipose Tissue

Amelogenins are enamel matrix proteins that play crucial roles in enamel formation. Previous studies have indicated that amelogenin and amelogenin C-terminal peptides have cell-signaling functions. Recently, adipocyte-derived mesenchymal stem cells (ADSCs) have received attention as a potential source of stem cells for use in regeneration therapy. In this study, we examined the effects of human full-length amelogenin (rh174) and amelogenin C-terminal peptide (amgCP) on the proliferation of ADSCs. ADSCs were cultured in the presence of amgCP or rh174. Cell proliferation was analyzed using BrdU immunoassay and MTS assay. Cell migration was evaluated by ELISA. The MAPK-ERK pathway was examined by phospho-p44/42 MAPK (Thr202/Tyr204) sandwich ELISA and western blotting. A specific MAPK inhibitor, U0126, was used to block ERK activity. ADSC proliferation and migration were significantly (P < 0.05) increased in the presence of rh174 or amgCP compared to non-treated control cells. The increased proliferation of ADSCs induced by rh174 or amgCP was significantly (P < 0.05) inhibited in the presence of 2 µg/ml U0126. The pERK/tERK ratio was significantly (P < 0.05) increased upon treatment with rh174 or amgCP compared to non-treated ADSCs, while this increase was significantly (P < 0.05) suppressed by the addition of U0126. Similar results were found by western blot analysis. In conclusion, amgCP and rh174 increase ADSC proliferation via the MAPK-ERK signaling pathway, and ADSCs may be useful for tissue regeneration in the orofacial region.

Success rates in isolating mesenchymal stem cells from permanent and deciduous teeth

Stem cells from human exfoliated deciduous teeth (SHED) and human dental pulp stem cells (hDPSCs) have emerged as attractive cell sources for bone regeneration. However, the specific teeth and the conditions most suitable for stem cell isolation remain unclear. Therefore, the success rate of SHED and hDPSCs isolation, the patient age and remaining root length in deciduous teeth were evaluated. Successful isolation was defined as when the cell culture was maintained up to the third passage without any contamination or other issues. Remaining tooth length was calculated using the root-to-crown ratio from patient X-rays and compared to the norm value from the literature. The overall successful isolation rate of SHED and hDPSCs was 82% and 70%. The average patient ages at extraction of the deciduous teeth and permanent teeth were 11 years and 9 months, and 22 years and 10 months respectively. In the successful SHED group, the average remaining root length of the anterior deciduous teeth was 71.4%, and that of the deciduous molars was 61.4%. Successful isolation appears to be associated with patient age, length of the remaining root, and also mechanical stress and other factors. Tooth selection criteria need to be identified to improve the success rate.

Neighborhood environment and physical activity among rural Japanese older adults

Background

Physical inactivity is one of the global health concerns. Rural populations in general tend to be more physically inactive and have higher risk for chronic conditions. Although numerous studies have assessed the association between neighborhood environment and physical activity to implement population level intervention, most are limited to urban adults. This study investigated potential neighborhood environment associated with physical activity for rural older adults in Japan.

Methods

The study subjects were from Shimane where is a rural-mountainous region in Japan. Those agreed to participate in the Shimane CoHRE study as of baseline (2010) and followed-up after 5 years were included in the analysis (mean age=71, n = 717). Subjects were asked if they engage in 30 minutes exercise more than twice a week at baseline and follow-up surveys. As a primary exposure, we computed mean land slope within 500 m street network buffer from residential point of each subject by geographic information system. Multiple logistic regression was conducted to estimate the odds of exercise engagement after 5 years by slope categorized in tertile, adjusting for age, BMI, and exercise habit at baseline.

Results

Significantly higher odds of exercise engagement was observed among those living in the hilly area compared to moderately hilly area after 5 years adjusting for baseline age, BMI, and exercise habit, (Odds ratio (OR): 1.71, 95% Confidence Interval (95%CI): 1.119, 2.616). There was no significant difference of odds between those in flat area and moderately hilly area (OR: 1.137, 95%CI: 0.738, 1.751).

Conclusions

This finding suggests that people living in hilly neighborhoods are more likely to maintain or start engaging in exercise after 5 years. Considering other potential environmental factors and farming culture within rural areas, future studies should capture various forms of environmental components and physical activity to dissect the mechanism.

Key messages

There are limited studies focus on rural older adults. Unique geographic feature in rural areas, i.e. hilly neighborhood might be associated with physical activity.

430Non-invasive estimation of right atrial pressure by IVC measurement differently predicts long-term prognoses in acute heart failure patients with reduced and preserved LVEF

Introduction

Inferior vena cava (IVC) measurement by bed-side echocardiography is a non-invasive, reproducible and feasible estimation of right atrial pressure (RAP). However, the effect of left ventricular systolic functions on the clinical efficacy of estimation of RAP using IVC parameters in hospitalized patients with acute heart failure (AHF) has not been fully discussed.

Purpose

We aimed to investigate the prognostic impact of RAP evaluation by IVC measurement in AHF patients, focusing on left ventricular ejection fraction (LVEF).

Methods

This observational study initially included 1,350 consecutive patients who were urgently hospitalized due to AHF. After the exclusion of patients receiving hemodialysis, those died in hospital, and those without full information of echocardiography during the index hospitalization, 507 patients with reduced (<40%; HFrEF) and 482 patients with preserved (≥40%; HFpEF) LVEF who discharged alive were respectively analyzed. In accordance with ESC guidelines, HFrEF and HFpEF patients were respectively divided into three groups depending on maximum IVC diameter and collapse; Normal-RAP group (IVC diameter ≤2.1cm and collapse >50%), High-RAP group (IVC diameter >2.1cm and collapse <50%), and Intermediate-RAP group (others). The endpoints of this study were cardiovascular (CV) death after the discharge, and hospitalization due to heart failure recurrence (HHF).

Results

During the observation period, 70 HFrEF patients (13.8%) and 51 HFpEF patients (10.5%) died by CV cause, and 223 HFrEF patients (43.9%) and 158 HFpEF patients (32.8%) were rehospitalized due to HF. In HFrEF patients, Kaplan-Meier analysis showed a low CV mortality rate only in the Normal-RAP group (Log-rank trend: P=0.001, Figure), but no significant difference in HHF rate among RAP groups (p=0.35, Figure). In multivariate Cox regression analysis, RAP classification was an independent predictor of CV mortality in HFrEF patients (adjusted hazard ratio (AHR) 1.90 [95% confidence interval (CI) 1.12–3.21)), even after the adjustment of diverse covariants. On the other hand, in HFpEF patients, Kaplan-Meier analysis showed the high mortality rate and HHF rate only in the High-RAP group (Log-rank trend: both p<0.001, Figure). Multivariate Cox regression analysis revealed that RAP classification independently predicted both prognoses (CV mortality: AHR 2.23 [95% CI 1.10–4.52]; HHF: AHR 1.34 [95% CI 1.03–1.74]) in HFpEF patients.

Figure 1

Conclusion

Non-invasive and easy classification of AHF patients by maximum IVC size and collapse may predict CV mortality after the discharge in HFrEF and HFpEF; while, it failed in HHF of HFrEF patients.