Do changes in working hours increase stress in Japanese white-collar workers?

Introduction: High stress at work is associated with negative health outcomes for workers, making stress prevention a critical challenge. Overtime work is an influential stress factor. This study, therefore, aimed to longitudinally evaluate how stress increased depending on changes in working hours among Japanese white-collar workers. Methods: We targeted 3,874 participants who were full-time workers and were recognized as having low stress in a web-based cohort in 2018 (T1) and 2019 (T2). We performed univariate and multivariate logistic regression with the following variables: years of experience, years of education, medical background, income, and roommates. Results: We observed a greater increase in stress among female who worked 41-50 h per week at T1 and more than 50 hours per week at T2, and those who worked more than 50 h per week at T1 and 35-40/41-50 h per week at T2, compared to those who worked 41-50 h per week both at T1 and T2, with odds ratios (ORs) and 95% confidence intervals (95% CI) of OR = 2.09, 95% CI (1.18, 3,70); OR =1.86, 95% CI (1.14, 3.03), respectively. However, no association between change in working hours and stress was found among male. Discussion: These results show that reducing stress requires decreasing working hours as well as identifying factors that lead to high stress.

A Generalized Structural Equation Model Approach to Long Working Hours and Near-Misses among Healthcare Professionals in Japan.

(1) Background: Near-miss incidents are the foundation of major injuries. They are warning signs that loss is imminent. Long working hours are a risk factor for near-misses along with sleep problems, job-related stress, and depressive symptoms. This study aimed to evaluate the indirect effects of long working hours via mediating variables on near-miss occurrences among Japanese healthcare professionals. (2) Methods: 1490 Japanese healthcare professionals' reports from a web-based survey of workers in October 2018 were analyzed to evaluate total, direct, and indirect effects of long working hours on near-misses. We applied a generalized structural equation model with three mediating variables: sleep problems, job-related stress, and depressive symptoms. (3) Results: The total effect and direct effect of the categories of working hours longer than 41 h per week (h/w) for occurrence of near-misses were not significantly higher than that of 35-40 h/w. However, for indirect effects on occurrence of near-misses that first passed through job-related stress, there were higher reports for each category compared to 35-40 h/w, with odds ratios (OR) and 95% confidence intervals (95% CI) of OR = 1.12, 95% CI (1.07, 1.21) for 41-50 h/w; 1.25, (1.14, 1.41) for 51-60 h/w; and 1.31, (1.18, 1.51) for ≥ 61 h/w. (4) Conclusion: The results suggest that reducing working hours might improve job-related stress, which could reduce near-misses and prevent injuries.

Separation of calcium-48 isotope by crown ether chromatography using ethanol/hydrochloric acid mixed solvent.

Benzo-18-crown-6 ether resin embedded in porous silica beads was synthesized and used as the packing material for chromatographic separation of (48)Ca isotope. The aim of the present work is to develop efficient isotope enrichment process for double ß decay nuclide (48)Ca. To this end, ethanol/HCl mixed solvent was selected as the medium for the chromatographic separation. Adsorption of calcium on the resin was studied at different HCl concentrations and different ethanol mixing ratios in batch-wise experiments. A very interesting phenomenon was observed; Ca adsorption is controlled not by the overall HCl concentration of the mixed solvent, but by the initial concentration of added HCl solution. Calcium break-through chromatography experiments were conducted by using 75v/v% ethanol/25v/v% 8M HCl mixed solvent at different flow rates. The isotope separation coefficient between (48)Ca and (40)Ca was determined as 3.8×10(-3), which is larger than that of pure HCl solution system. Discussion is extended to the chromatographic HETP, height equivalent to a theoretical plate.

Cilostazol strengthens barrier integrity in brain endothelial cells.

We studied the effect of cilostazol, a selective inhibitor of phosphodiesterase 3, on barrier functions of blood-brain barrier (BBB)-related endothelial cells, primary rat brain capillary endothelial cells (RBEC), and the immortalized human brain endothelial cell line hCMEC/D3. The pharmacological potency of cilostazol was also evaluated on ischemia-related BBB dysfunction using a triple co-culture BBB model (BBB Kit™) subjected to 6-h oxygen glucose deprivation (OGD) and 3-h reoxygenation. There was expression of phosphodiesterase 3B mRNA in RBEC, and a significant increase in intracellular cyclic AMP (cAMP) content was detected in RBEC treated with both 1 and 10 µM cilostazol. Cilostazol increased the transendothelial electrical resistance (TEER), an index of barrier tightness of interendothelial tight junctions (TJs), and decreased the endothelial permeability of sodium fluorescein through the RBEC monolayer. The effects on these barrier functions were significantly reduced in the presence of protein kinase A (PKA) inhibitor H-89. Microscopic observation revealed smooth and even localization of occludin immunostaining at TJs and F-actin fibers at the cell borders in cilostazol-treated RBEC. In hCMEC/D3 cells treated with 1 and 10 µM cilostazol for 24 and 96 h, P-glycoprotein transporter activity was increased, as assessed by rhodamine 123 accumulation. Cilostazol improved the TEER in our triple co-culture BBB model with 6-h OGD and 3-h reoxygenation. As cilostazol stabilized barrier integrity in BBB-related endothelial cells, probably via cAMP/PKA signaling, the possibility that cilostazol acts as a BBB-protective drug against cerebral ischemic insults to neurons has to be considered.

Deagglomeration and surface modification of thermally annealed nanoscale diamond.

Thermally annealed nanodiamond has been functionalized by C-C coupling of the partially graphitized diamond surface using aryl diazonium salts. Depending on the terminal functional groups, the modified bucky diamond nanoparticles show good solubility (up to 0.63mgmL(-1)) in different solvents. The agglomerate size of the originally strongly bound detonation diamond (>0.5µm) is substantially reduced to ∼20-50nm by this chemical procedure and without using mechanical techniques such as strong ultrasound or milling. Arylation with functionalized aryl diazonium salts carrying COOH, SO(3)H, NO(2) or bromoethyl groups opens the way for further covalent grafting of organic structures. Arylation with Ar-COOH or Ar-SO(3)H leads to the formation of stable colloidal solutions in water and physiological media (i.e. PBS buffer), an important prerequisite for biomedical applications.

A general procedure to functionalize agglomerating nanoparticles demonstrated on nanodiamond.

Upon reduction of particle size to the nanometer range, one has to deal with the general issue of spontaneous agglomeration, which often obstructs postsynthesis modification of nanoparticle surfaces. A technique to cope with this phenomenon is required to realize a wide variety of applications using nanoparticles in solvents or as refined assemblies. In this article, we report on a new technique to facilitate surface chemistry of nanoparticles in a conventional glassware system. A beads-assisted sonication (BASD) process was examined to break up persistent agglomerates of nanodiamonds in two different reactions for simultaneous surface functionalization. The chosen reactions are the silanization with an acrylate-modified silane and the arylation using diazonium salts. The BASD process can be successfully applied even where the original material is not dispersible in the reaction solvent at all, as the formation of ever smaller, increasingly functionalized agglomerates is improving their solubility. We have confirmed that the presence of ceramic beads enables functionalization of each primary particle, while conventional magnetic stirring or beadless sonication can reach primary particles only when agglomeration is loose. Additionally, mechanical surface modification of nanodiamond was found to take place by BASD with high energy density, leading to sp(2)-hybridized surface patches on nanodiamond. This allowed for the efficient grafting of aryl groups to the surface of primary diamond nanoparticles. Stable, homogeneously functionalized nanodiamond particles in colloidal solution can be obtained by this method.

Improved septal contraction and coronary flow velocity after cardiac resynchronization therapy elucidated by strain imaging and pulsed wave Doppler echocardiography.

OBJECTIVES: The effects of cardiac resynchronization therapy (CRT) with various atrioventricular conduction delay settings were investigated on cardiac hemodynamic changes involved in coronary flow velocity using color and pulsed wave Doppler modalities and myocardial regional contractility using a novel echocardiographic technique (strain imaging). METHODS: Seven patients with advanced heart failure (left ventricular ejection fraction < 35%) and left bundle branch block(QRS > or = 140 msec) were treated with CRT. Color and pulsed wave Doppler imaging were performed from the apical four-chamber view to examine the cardiac functions such as stroke volume, cardiac output, mitral regurgitant volume and coronary flow velocity. Strain imaging was performed to quantify the asynchrony of both intraventricular and interventricular time delay between the septum and left ventricular free wall (posterior wall) and to assess the regional contractile function. Wall motion was also evaluated. RESULTS: Intraventricular and interventricular asynchrony were improved from 173 +/- 18 to 60 +/- 6 msec, and 69 +/- 25 to 12 +/- 3 msec, respectively. Stroke volume (55.2 +/- 6.2 to 76.8 +/- 10.8 ml; 39% up), cardiac output (3.9 +/- 0.3 to 5.4 +/- 0.5 I/min; 38% up) and coronary flow velocity (24 +/- 3 to 36 +/- 5 cm/sec; 50% up) were greatly increased and mitral regurgitant volume (59.7 +/- 18.0 to 38.9 +/- 11.3 ml; 35% down)was clearly decreased. Septal wall shortening was greatly increased from 10.2 +/- 2.3% to 17.0 +/- 1.8% and septal wall motion (radial thickening)was also improved simultaneously. Atrioventricular interval settings influenced all above parameters. CONCLUSIONS: CRT improved the cardiac hemodynamics involved in coronary flow significantly due to both resynchronization of inter and intra asynchrony, and improvement of the regional myocardial contraction in patients with severe congestive heart failure and complete left bundle branch block.

Predicting prognosis based on the shape of the left ventricular cavity in dilated cardiomyopathy: analysis using rate of improvement in the circle index.

PURPOSE: To elucidate the relation between a quantitative measure of the shape of the left ventricular cavity, cardiac function, and prognosis in patients with dilated cardiomyopathy (DCM). METHODS: The hearts of 20 healthy individuals and 18 patients with DCM were evaluated. Participants were aged 48.5 ± 5.0 years. On the basis of end-systolic four-chamber view echocardiograms, the endocardium of the left ventricle was traced and the resulting curve was segmented using 100 points. A line tangential to the curve was then drawn at each point, and the angle between two adjacent tangential lines was calculated. The deviation of these angles was designated as the circle index. The circle index and hemodynamic findings in patients with DCM were compared, and the rate of improvement in the circle index in these cases of DCM was determined. These patients were then placed into one of two groups: group R (11 patients), those with improvement rates of 10% or higher at time of discharge; and group NR (seven patients), those with rates less than 10%. Diuretic (furosemide) use, New York Heart Association (NYHA) classification, and readmission rate for the two groups were compared 2 years after discharge. RESULTS: The circle index was 2.7 ± 0.9 in the DCM group and 17.5 ± 4.2 in the healthy group (P < 0.01). The circle index in the DCM group was correlated with pulmonary capillary wedge pressure (r(2) = 0.42). Use of furosemide was unchanged in group R 2 years after discharge, but had increased for all patients in group NR. All cases in group R were classified as NYHA I 2 years after discharge. In group NR, in contrast, although all cases were classified as NYHA I at discharge, five of seven cases had deteriorated to NYHA III-IV 2 years later and were readmitted to hospital. CONCLUSION: There appears to be a quantifiable correlation between the circularity of the left ventricular cavity and the circle index. This suggests that rate of improvement after treatment for heart failure could predict prognosis in patients with DCM.

Effect of alcohols on elution chromatography of trivalent actinides and lanthanides using tertiary pyridine resin with hydrochloric acid-alcohol mixed solvents.

Elution chromatography with a tertiary pyridine resin has been used to separate the trivalent actinides (An3+) from the lanthanides (Ln3+) using an alcoholic hydrochloric acid solvent. Trivalent Am and Cm were separated from the Ln by employing a 1 cm(phi) x 10 cm resin column with the mixed solvent system composed of concentrated hydrochloric acid (HCl) and alcohols. The distribution coefficients (Kd) and the separation factors between An and Ln (alpha(An)(Ln)) increased as the alcohol content of the solvent mixture increased. On the other hand, the Kd and alpha(An)(Ln) decreased drastically upon the addition of water to the solvent mixture. Among the four alcohols investigated (methanol, ethanol, n-propanol and n-butanol), the ethanol-HCl mixed solvent system showed the largest Kd and alpha(An)(Ln). The mechanism of adsorption for An and Ln cations on the pyridine resin is discussed in addition to the results presented herein.

Significance of low-dose dobutamine stress echocardiography for the prediction of the long-term prognosis for patients with acute myocardial infarction.

OBJECTIVES: Detection of stunned myocardium using low-dose dobutamine stress echocardiography is a good predictor of improvement of cardiac function in patients with acute myocardial infarction during short hospital stays. The present study evaluated the detection of stunned myocardium as a predictor of the long-term prognosis for patients with acute myocardial infarction. METHODS: One hundred and two patients (83 males, 19 females, mean age 61.5 years) with initial myocardial infarction underwent successful reperfusion therapy (direct percutaneous transluminal coronary angioplasty or stent) in the acute stage. Within 7 days, low-dose dobutamine was administered by intravenous drip and improvement of wall motion of the infarct area was evaluated by echocardiography. The patients were divided into two groups, the viable group that showed one grade or more improvement (61 patients), and the non-viable group that showed no improvement (41 patients). These groups were compared to determine the differences in clinical findings such as remodeling of the left ventricle measured by two-dimensional echocardiography, physical work capacity during serial multi-step exercise testing, and the prognosis. RESULTS: The viable group showed greater improvement in hemodynamics and wall motion of the infarct areas than the non-viable group. After discharge, the physical work capacity was significantly increased and there was no recognizable enlargement of the left ventricle in the viable group. No sudden cardiac death or heart failure occurred in the viable group, in contrast to incidences of 6% and 9%, respectively, in the non-viable group. Unstable angina and nonfatal re-infarction occurred more frequently in the viable group. CONCLUSIONS: The presence of stunned myocardium is a predictor of the prognosis for patients with acute myocardial infarction.