The purification, amino acid sequence, and two-dimensional 1H NMR results are reported for the rubredoxin (Rd) from the hyperthermophilic archaebacterium Pyrococcus furiosus, an organism that grows optimally at 100 degrees C. The molecular mass (5397 Da), iron content (1.2 +/- 0.2 g-atom of Fe/mol), UV-vis spectrophotometric properties, and amino acid sequence (60% sequence identity with Clostridium pasteurianum Rd) are found to be typical of this class of redox protein. However, P. furiosus Rd is remarkably thermostable, being unaffected after incubation for 24 h at 95 degrees C. One- and two-dimensional 1H nuclear magnetic resonance spectra of the oxidized [Fe(III)Rd] and reduced [Fe(II)Rd] forms of P. furiosus Rd exhibited substantial paramagnetic line broadening, and this precluded detailed 3D structural studies. The apoprotein was not readily amenable to NMR studies due to apparent protein oxidation involving the free cysteine sulfhydryls. However, high-quality NMR spectra were obtained for the Zn-substituted protein, Zn(Rd), enabling detailed NMR signal assignment for all backbone amide and alpha and most side-chain protons. Secondary structural elements were determined from qualitative analysis of 2D Overhauser effect spectra. Residues A1-K6, Y10-E14, and F48-E51 form a three-strand antiparallel beta-sheet, which comprises ca. 30% of the primary sequence. Residues C5-Y10 and C38-A43 form types I and II amide-sulfur tight turns common to iron-sulfur proteins. These structural elements are similar to those observed by X-ray crystallography for native Rd from the mesophile C. pasteurianum. However, the beta-sheet domain in P. furiosus Rd is larger than that in C. pasteurianum Rd and appears to begin at the N-terminal residue. From analysis of the secondary structure, potentially stabilizing electrostatic interactions involving the charged groups of residues Ala(1), Glu(14), and Glu(52) are proposed. These interactions, which are not present in rubredoxins from mesophilic organisms, may prevent the beta-sheet from "unzipping" at elevated temperatures.

BackgroundDelirium after cardiac surgery is associated with serious long-term negative outcomes and high costs. The aim of this study is to evaluate neurobehavioral, hemodynamic, and sedative characteristics of dexmedetomidine, compared with the current postoperative sedative protocol (remifentanil) in patients undergoing open heart surgery with cardiopulmonary bypass (CPB).MethodsOne hundred and forty two eligible patients who underwent cardiac surgery on CPB between April 2012 and March 2013 were randomly divided into two groups. Patients received either dexmedetomidine (range, 0.2 to 0.8 μg/kg/hr; n=67) or remifentanil (range, 1,000 to 2,500 μg/hr, n=75). The primary end point was the prevalence of delirium estimated daily via the confusion assessment method for intensive care.ResultsWhen the delirium incidence was compared with the dexmedetomidine group (6 of 67 patients, 8.96%) and the remifentanil group (17 of 75 patients, 22.67%) it was found to be significantly less in the dexmedetomidine group (p<0.05). There were no statistically significant differences between two groups in the extubation time, ICU stay, total hospital stay, and other postoperative complications including hemodynamic side effects.ConclusionThis preliminary study suggests that dexmedetomidine as a postoperative sedative agent is as sociated with significantly lower rates of delirium after cardiac surgery.

BackgroundPresenteeism, a concept that has recently undergone active study, is the act of attending work while sick. This study investigates the association between presenteeism and various psychosocial factors within workplaces.MethodsThis study analyzed 29246 wage earners from the third Korean Working Conditions Survey (KWCS, 2011) data using the logistic regression analysis to investigate the association between presenteeism and various psychosocial factors within workplaces.ResultsAmong the 29246 wage earners, 6347 (21.7 %) showed presenteeism. Those who experienced age discrimination at work (adjusted odds ratio (aOR) 1.77: 95 % CI 1.56–2.00), educational background discrimination (aOR 1.35: 95 % CI 1.22–1.51), regional discrimination (aOR 1.55: 95 % CI 1.31–1.83), sexual discrimination (aOR 1.65: 95 % CI 1.41–1.94), employment type discrimination (aOR 2.13: 95 % CI 1.89–2.40), physical violence (aOR 1.92: 95 % CI 1.45–2.55), sexual harassment (aOR 2.90: 95 % CI 2.01–4.19), job insecurity (aOR 1.36: 95 % CI 1.18–1.56), work–life imbalance (aOR 1.38: 95 % CI 1.29–1.47), low job satisfaction (aOR 2.04: 95 % CI 1.91–2.17), no colleague support (aOR 1.11: 95 % CI 1.02–1.21), job stress (aOR 1.89: 95 % CI 1.76–2.02), emotional labor (aOR 1.50: 95 % CI 1.41–1.60), high work intensity (aOR 1.31: 95 % CI 1.23–1.38), and 3 groups of job strain that are passive group (aOR 1.09: 95 % CI 1.00–1.18), active group (aOR 1.39: 95 % CI 1.28–1.51), and high strain group (aOR 1.35: 95 % CI 1.24–1.46) showed an increased risk of presenteeism compared to their respective counterparts (p < 0.01).ConclusionsThe study results confirmed the association between presenteeism and various psychosocial factors within workplaces. Considering that presenteeism negatively affects productivity and the mental and physical health of individuals, managing various psychosocial factors within workplaces is proposed to reduce presenteeism.

PurposeThe purpose of this study was to assess the association of organizational factors with work-related sleep problems (WRSP) among Korean workers.MethodsThe data were derived from the First Korean Working Conditions Survey conducted in 2006 with a representative sample of the Korean working population (n = 10,039).ResultsThe overall prevalence of WRSP was 5.1  % (95  % confidence interval (CI) 4.7–5.5). Those who experienced sexual harassment at work (adjusted odds ratio (aOR) 3.47: 95 % CI 1.77–6.81), discrimination due to sex (aOR 2.44: 95 % CI 1.36–4.36) or age (aOR 2.22: 95 % CI 1.52–3.23), violence at work (aOR 1.98: 95 % CI 1.06–3.68), threat of violence (aOR 1.96: 95 % CI 1.05–3.66), poor work-life balance (aOR 1.78: 95 % CI 1.44–2.20), low job satisfaction (aOR 1.69: 95 % CI 1.37–2.09), high cognitive (OR 1.64: 95 % CI 1.32–2.03) and emotional (aOR 1.53: 95 % CI 1.22–1.91) demands, job insecurity (aOR 1.32: 95 % CI 1.07–1.63), and high work intensity (aOR 1.55: 95 % CI: 95 % CI 1.25–1.92) had an increased risk of WRSP compared to their respective counterparts (p < 0.01). Low social support was not significantly associated with WRSP (aOR 0.88: 95 % CI 0.67–1.15).ConclusionThe results revealed that poor psychosocial working conditions may be related to a high prevalence of WRSP among representative Korean workers.

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Background Little is known about the association between psychosocial factors and injury absence in the workplace. Purpose This study aims to assess the association of comprehensive workplace psychosocial factors with work-related injury absence among Korean workers. Methods The data (n=7,856) were derived from the First Korean Working Conditions Survey conducted in 2006 with a representative sample (n=10,043) of the Korean working population. The survey instrument contained questions about hours of work, physical risk factors, work organization, and the effect of work on health/injury. Work-related injury absence was indicated by a dichotomous variable with at least 1 day absence during the preceding 12 months. Logistic regression models were used to calculate odds ratio and confidence interval (CI). Incremental adjustments for sociodemographic, health behavior, and occupational confounding variables were employed in the models. Results The overall 1-year prevalence of work-related injury absence in this study was 1.37 % (95 % CI, 1.11–1.63 %). Those who experienced violence at work (adjusted odds ratio (aOR), 7.05 (95 % CI, 2.69–18.5)), threat of violence at work (aOR, 4.25 (95 % CI, 1.32–13.64)), low job autonomy (aOR, 1.79 (95 % CI, 1.17–2.74)), and high job strain (aOR, 2.38 (95 % CI, 1.29–4.42) had an increased risk of injury absence, compared with their respective counterparts (p<0.05). Among all job types, skilled workers in Korea were at a near fourfold risk of work absence due to occupational injuries, compared with managers in low-risk jobs. Conclusion Workplace violence and increased job strain were two key workplace psychosocial factors associated with work-related injury absence.

J 2799 the hydrolysis of a-TAc stereoisomers is an intrinsic property of cholesterol esterases. The data for pure PCE (Table I, footnote 6 ) show as much as a 60-fold and 14-fold range in RRRJSRR selectivity in the noncompetitive and competitive experiments, respectively. Interestingly, in the competitive experiments the rate of hydrolysis of RRR-a-TAc is significantly affected but that of SRR-a-TAc is little affected relative to the corresponding rates measured in the noncompetitive experiments.Is At 40 mM the bile salts will form mixed micellesz0 with the DMPC (2 mM) and a-TAc (0.1-0.2 mM). Although the initial rates of hydrolysis can be described by using classical Michaelis-Menten (MM) kinetics,8 we are not, of course, dealing with a molecular solution of a-TAc but with micellized a-TAc which presumably reacts with the water-soluble BCE or PCE at the micellewater interface.z1 The effect of the (chiral) bile salts on the relative (and absolute) rates of hydrolysis of RRR-and SRR-a-TAc could result from diastereoisomeric influences upon the epimeric acetates induced within the mixed micelle itself or, alternatively, may arise from direct bile salt-protein interaction^.'^ The degree of chiral recognition that is achieved is genuinely dramatic in view of the fact that the chiral center is separated by six bonds from the bond that is cleaved by the enzyme.z3 (21) Such two-dimensional systems can appear to follow MM kinetics (even including product inhibition), but the derived kinetic parameters have more complicated meanings than for homogeneous enzyme reaction^.'^**^ (22) Verger, R.; Mieras, M. C. E.; de Haas, G. H. J. Biol. Chem. 1973, 248,4023-4034. Verger, R.; de Haas, G. H. Annu. Reu. Biophys. Bioeng.(23) It was recently reported6 that a lipase treated with an organic solvent and deoxycholate is converted to a form that is more enantiosclective toward hydrolysis of a variety of (+)-arylpropionic and (+)-phenoxypropionic esters.In these cases, however, the chiral center is separated by only a single bond from the bond that is cleaved. 1976, 5,77-I 17.Cubane-type [Fe4S4] clusters functionalized by non-cysteinyl and/or unique ligation of a specific Fe or by replacement of one Fe by another transition metal (e.g., Mo, V, or Ni) have been proposed as components of the active sites of a range of metal-

The metal-catalyzed reaction of olefins with allylamines bearing coordination sites (2-pyridyl groups) was studied. With Ru 3 (CO) 12 as catalyst, activation of C−H bonds led to the formation of ketimines that were hydrolyzed to give asymmetric ketones. With [(C 8 H 14 ) 2 RhCl] 2 , both C−H and C−C bonds were activated and symmetric ketones were formed on hydrolysis. The reaction involves double bond migration of the allylamine to form an aldimine.Catalytic activation of C-H 1,2 and C-C 3,4 bonds has a broad impact in organometallic chemistry because of its applications in organic synthesis. Aldehydic C-H bond activation 5 and chelation-assisted hydroacylation 6 were described earlier.In particular, the use of 2-amino-3-picoline avoids decarbonylation effectively. 7 Activation of the C-C bond in ketones bearing β-hydrogen using chelation assistance has also been documented. 8 Aldimines and ketimines are postulated intermediates for these C-H and C-C bond activations. Catalytic activation of aromatic aldehydes with 2-amino-3-picoline is more efficient than activation of aliphatic aldehydes. 7a,9 The formation of aminal side products during the reaction with aliphatic aldehydes reduces the yields. Double bond migration of allylamines in the presence of transition metal complexes provides a versatile approach to the preparation of aldimines of the aliphatic alkyl group. 10