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Objective: Drawing on a sample of hospital physicians, we attempted to determine prospective associations between three job demands, work-related strain and perceived quality of care., Design: Longitudinal follow-up study with with a 1-year time lag., Setting: Physicians of two acute-care hospitals in Germany (one general urban and one children's hospital)., Study Participants: Ninety-five physicians filled out a standardized questionnaire., Main Outcomes Measures: Physicians' evaluations of quality of care at both waves., Results: Our results support the hypothesis that job demands directly influence quality of care irrespective of strain. Specifically, high social stressors (β = -0.15, P = 0.036) and time pressure (β = -0.19, P = 0.031) were associated with decreased quality of care over time. We additionally observed reversed effects from quality of care at baseline to time pressure at follow-up (β = -0.35, P = 0.006). Contrary to expectations, physicians' work-related strain did not mediate the job demands-quality of care-relationship, nor were strain-to-stressor effects observed., Conclusions: Our results corroborate that hospital work environments with high demands have a direct impact on physician-perceived quality of care. In turn, poor care practices contribute to increased job demands. Our findings also emphasize that further understanding is required of how physicians' workplace conditions affect job demands, well-being, and quality of care, respectively., (© The Author 2016. Published by Oxford University Press in association with the International Society for Quality in Health Care. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com)

Polypeptides remaining tightly associated with isolated genomic DNA are of interest with respect to their potential involvement in the topological organization and/or function of genomic DNA. Such residual DNA-polypeptide complexes were used for raising monoclonal antibodies by in vitro immunization. Screening of a murine lambdagt11 cDNA library with these antibodies released a positive cDNA (MC1D) encoding a 16 kDa polypeptide. The cloned homologous human cDNA (HC1D) was identified in the dbest data base by partial sequence comparison, and it was sequenced full length. The cDNA-derived amino acid sequences comprise nuclear location signals but none of the known DNA-binding motifs. However, the recombinantly expressed proteins show in vitro DNA binding affinities. A polyclonal antiserum to the recombinant MC1D protein immunostains sub-nuclear structures, and it detects a residual 16 kDa polypeptide on western blots of DNA digests. These results support the conclusion that the cloned cDNAs reflect mRNAs encoding one of the chemically-resistant polypeptides which can be detected in isolated genomic DNA by sensitive techniques, e.g. by125Iodine labeling and SDS-PAGE.

Cell lysis in presence of SDS and proteinase K followed by salting-out of residual polypeptides by dehydration and precipitation with saturated sodium chloride solution [Miller, S.A., Dykes, D.D. and Polesky, H.F., Nucleic Acids Res., 16, 1215, 1988] efficiently resolves deproteinized DNA. However, this DNA is still associated with prominent polypeptides which remain stably attached to DNA during further treatments, e.g. during repeated salting-out steps, prolonged incubation of DNA in 1% SDS or 4 M urea at 56 degrees C and ethanol precipitation. The persistent polypeptides (62, 52 and 40 kDa) released from Ehrlich ascites cell DNA were further characterized. Microsequencing indicates that the DNA binding polypeptides are not yet characterized at the sequence level. Nuclease digestion of the DNA releases stable DNA-protein complexes with the shape of globular particles (12.8 +/- 0.8 nm) and their larger aggregates in which DNA remains protected from nuclease digestion. The isolated DNA-polypeptide complexes show ATPase (Km = 7.4 x 10(-4) M) and protein kinase activity. Antibodies reveal a parallel distribution of the complexes with chromatin, however, the complexes are retained in chromatin-depleted nuclei.

In a natural population of Drosophila persimilis (McDonald Ranch, Napa Valley, California), KL and MD chromosomal arrangement frequencies undergo a seasonal cycle, with MD common in spring and KL common in summer. Samples collected from spring and summer provided isofemale strains established as homozygous KL and MD pairs (kinlines) with each pair derived from a single heterokaryotype wild progenitor. Haploid doses of chromosomes 2 and 4 were controlled by marker-cross derivations of kinlines. Percentage onset of female receptivity was measured from cultures at 25 degrees and at 15 degrees , using ten kinlines from spring and nine from summer collections, with fast-mating hybrid males as standard testers. Mating tests consisted of 20 tester males x 20 females of specific age, karyotype, and kinline observed for 30 min. At 25 degrees females became receptive at 48 hr after eclosion: parental line (KL(i)/KL(i) and MD(i)/MD(i)) females were approximately equal at 55 to 60% receptive, while among hybrids, MD(i)/MD(j) homokaryotype females were significantly less receptive (68%) than all other outbred combinations (73 to 77%). At 15 degrees , females became receptive at four days of age, with increases on the fifth and sixth days: both parental line and outbred MD/MD females were significantly more receptive (28% at four days and 62% at six days) than all heterokaryotype females (20 to 26% at four days and 55 to 59% at six days), which in turn were more receptive than KL/KL parental and outbred females (10% at four days and 40% at six days). Heterosis was expressed at 25 degrees , but not at 15 degrees . Thus, dominance for female receptivity was temperature dependent. Females polymorphic for these third chromosomal karyotypes possess differential temperature sensitivity for onset of receptivity and are likely to contribute in a significant way to the observed seasonal frequency cycle in the natural population from which they have been derived.