セイシンカ ニンチショウ チリョウ ビョウトウ ニ オケル カンゴシ ノ ショクギョウセイ ストレス

熊本大

Novel Extracellular x-Prolyl Dipeptidyl-Peptidase (DPP) from Streptococcus gordonii FSS2: an Emerging Subfamily of Viridans Streptococcal x-Prolyl DPPs

Streptococcus gordonii is generally considered a benign inhabitant of the oral microflora, and yet it is a primary etiological agent in the development of subacute bacterial endocarditis (SBE), an inflammatory state that propagates thrombus formation and tissue damage on the surface of heart valves. Strain FSS2 produced several extracellular aminopeptidase and fibrinogen-degrading activities during growth in culture. In this report we describe the purification, characterization, and cloning of a serine class dipeptidyl-aminopeptidase, an x-prolyl dipeptidyl-peptidase (Sg-xPDPP, for S. gordonii x-prolyl dipeptidyl-peptidase), produced in a pH-controlled batch culture. Purification of this enzyme by anion exchange, gel filtration, and hydrophobic interaction chromatography yielded a protein monomer of approximately 85 kDa, as shown by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (PAGE) under denaturing conditions. However, under native conditions, the protein appeared to be a homodimer on the basis of gel filtration and PAGE. Kinetic studies indicated that purified enzyme had a unique and stringent x-prolyl specificity that is comparable to both the dipeptidyl-peptidase IV/CD26 and lactococcal x-prolyl dipeptidyl-peptidase families. Nested PCR cloning from an S. gordonii library enabled the isolation and sequence analysis of the full-length gene. A 759-amino-acid polypeptide with a theoretical molecular mass of 87,115 Da and a calculated pI of 5.6 was encoded by this open reading frame. Significant homology was found with the PepX gene family from Lactobacillus and Lactococcus spp. and putative x-prolyl dipeptidyl-peptidases from other streptococcal species. Sg-xPDPP may serve as a critical factor for the sustained bacterial growth in vivo and furthermore may aid in the proteolysis of host tissue that is commonly observed during SBE pathology

Leadership Effectiveness:A Supervisor's Approach to Manage Return to Work

<p>Purpose To investigate adaptive leadership in relation to personnel sickness absence (SA). In situational leadership, supervisors are effective if they adapt their leadership style appropriately to a given situation. Methods A managerial reorganization in a Dutch hospital with reassignment of supervisors provided the opportunity to compare SA in the same wards while under the leadership of different supervisors. Leadership effectiveness was measured with the Leader Effectiveness and Adaptability Description (LEAD). Personnel SA was retrieved from employer's records and cumulated at the individual level, distinguishing between short-term (1-7 day) and long-term (> 7 days) SA. Cumulated SA days and mean SA lengths before and after managerial reorganization were compared at the individual level by using non-parametric paired statistical analyses. Employer's costs to compensate sick-listed employees' salaries before and after reorganization were cumulated and compared at ward level by using non-parametric statistics. Results 6 wards (N = 403) retained the same supervisor, 6 wards (N = 504) were assigned more effective supervisors, and 4 wards (N = 184) got less effective supervisors than the ones before reorganization. Cumulated short-term SA days and lengths did not change with leadership effectiveness. Employees who got more effective supervisors had fewer long-term SA days and shorter long-term SA lengths than before reorganization. More effective supervisors saved an average of 21,368 Euros per ward, particularly due to less long-term SA. Conclusions Long-term SA was shorter after employees got more effective supervisors. Adaptive supervisors can facilitate return to work and save SA costs by providing the right type of support to sick-listed employees.</p>

2.5 Radical–Polar Crossover Reactions

International audienceAbstract Radical–polar crossover reactions, that is, single-electron redox events allowing for the interconversion between radical and ionic intermediates, make it possible to connect radical and polar processes in the same synthetic transformation. Such a combination is the basis of much original synthetic methodology, which is particularly useful in the context of domino, tandem, or multicomponent reactions. This chapter comprehensively covers the field of radical–polar crossover reactions, with a primary emphasis on transformations wherein both the radical and polar processes provide synthetic elaboration