Lessons for non-VA care delivery systems from the U.S. Department of Veterans Affairs Quality Enhancement Research Initiative: QUERI Series

The U.S. Veterans Health Administration (VHA) may have a very different structure and function from the organizations and practices that provide medical care to most Americans, but those organizations and practices could learn a lot from the VHA's Quality Enhancement Research Initiative (QUERI). There are at least six topics of increasing importance for implementation research where QUERI experience should be of value to other non-VHA organizations, both within and external to the United States: 1) Researcher-clinical leader partnerships for care improvement; 2) Attention to culture, capacity, leadership, and a supportive infrastructure; 3) Practical economic evaluation of quality implementation efforts; 4) Human subject protection problems; 5) Sustainability of improvements; and 6) Scale-up and spread of improvements. The articles in Implementation Science's QUERI Series provide the details of those lessons for others who are willing to invest the time to translate them into their different settings.     

Human Regulatory Subunit RIβ of cAMP-Dependent Protein Kinases: Expression, Holoenzyme Formation and Microinjection into Living Cells

The human regulatory subunit RIβ of cAMP-dependent protein kinases was expressed in Escherichia coli as a fusion protein with glutathione S -transferase. Purification was performed by affinity chromatography on glutathione-agarose beads after cleavage with thrombin. The human recombinant Riff protein migrated at 55 kDa on SDS-PAGE and displayed immunoreactivity with an anti-human RIβ antiserum. Furthermore, the purified recombinant RIβ protein was shown to exist as a dimer that was able to form holoenzyme with the catalytic subunit Cα. The rate of RIβ₂Cα₂ holoenzyme formation was faster in the presence than in the absence of MgATP. The kinase activity measured before and after adding cAMP to the holoenzyme showed that the presence of cAMP resulted in holoenzyme dissociation and release of active Cα-subunit, due to cAMP binding to RIβ. Compared to a RIα₂Cα₂ holoenzyme, the RIβ₂Cα₂ holoenzyme exhibited a more than twofold higher sensitivity to cAMP. The subcellular localization of Riff was analyzed in quiescent REF-52 fibroblasts and Wistar rat thyroid (WRT) cells after microinjection of fluorescently labeled proteins into the cytoplasm. A cytoplasmic distribution was observed when free RIβ was injected, whereas free Cα injected into the cytoplasm appeared in the nucleus. When holoenzymes with labeled Riff and unlabeled Cα, or unlabeled RIβ and labeled Cα, were injected, unstimulated cells showed fluorescence in the cytoplasm of both cell types. REF-52 cells stimulated with 8-bromo-cAMP (8-Br-cAMP) and WRT cells treated with thyrotropin (TSH) showed fluorescence mainly in the cytoplasm when RIβ was the labeled subunit of the in vivo dissociated bioenzyme. In contrast, nuclear fluorescence was evident from the release and translocation of labeled Cα from the holoenzyme complex after stimulation with 8-Br-cAMP or TSH.     

X-linked and lineage-dependent inheritance of coping responses to stress

Coping—or how one routinely deals with stress—is a complex behavioral trait with bearing on chronic disease and susceptibility to psychiatric disorders. This complexity is a result of not only underlying multigenic factors, but also important non-genetic ones. The defensive burying (DB) test, although originally developed as a test of anxiety, can accurately measure differences in coping strategies by assaying an animals behavioral response to an immediate threat with ethological validity. Using offspring derived from reciprocal crosses of two inbred rat strains differing in DB behaviors, we provide convergent phenotypic and genotypic evidence that coping styles are inherited in an X-linked fashion. We find that first-generation (F₁) males, but not females, show maternally derived coping styles, and second-generation (F₂) females, but not males, show significant differences in coping styles when separated by grandmaternal lineage. By using a linear modeling approach to account for covariate effects (sex and lineage) in QTL analysis, we map three quantitative trait loci (QTL) on the X Chromosome (Chr) (Coping-1, Approach-1, and Approach-2) associated with coping behaviors in the DB paradigm. Distinct loci were associated with different aspects of coping, and their effects were modulated by both the sex and lineage of the animals, demonstrating the power of the general linear modeling approach and the important interplay of allelic and non-allelic factors in the inheritance of coping behaviors.     

Mapping of the regulatory subunits RI beta and RII beta of cAMP-dependent protein kinase genes on human chromosome 7.

The genes encoding the regulatory subunits RI beta (locus PRKAR1B) and RII beta (locus PRKAR2B) of human cAMP-dependent protein kinase have been mapped in the basic CEPH (Centre d'Etude du Polymorphisme Humain) family panel of 40 families to chromosome 7p and 7q, respectively, using the enzymes HindIII and BanII recognizing the corresponding restriction fragment length polymorphisms (RFLPs). Previous data from the CEPH database and our present RFLP data were used to construct a six-point local framework map including PRKAR1B and a seven-point framework map including PRKAR2B. The analysis placed PRKAR1B as the most distal of the hitherto mapped 7p marker loci and resulted in an unequivocal order of pter-PRKAR1B-D7S21-D7S108-D7S17-D7S149- D7S62-cen, with a significantly higher rate of male than female recombination between PRKAR1B and D7S21. The 7q regulatory gene locus, PRKAR2B, could also be placed in an unambigous order with regard to the existing CEPH database 7q marker loci, the resulting order being cen-D7S371-(COL1A2,D7S79)-PRKAR2B-MET-D7S87++ +-TCRB-qter. Furthermore, in situ hybridization to metaphase chromosomes physically mapped PRKAR2B to band q22 on chromosome 7.     

The response of malignant B lymphocytes to ionizing radiation: cell cycle arrest, apoptosis and protection against the cytotoxic effects of the mitotic inhibitor nocodazole

Ionizing radiation and mitotic inhibitors are used for the treatment of lymphoma. We have studied cell cycle arrest and apoptosis of three human B-lymphocyte cell lines after X irradiation and/or nocodazole treatment. Radiation (4 and 6 Gy) caused arrest in the G(2) phase of the cell cycle as well as in G(1) in Reh cells with an intact TP53 response. Reh cells, but not U698 and Daudi cells with defects in the TP53 pathway, died by apoptosis after exposure to 4 or 6 Gy radiation (>15% apoptotic Reh cells and <5% apoptotic U698/Daudi cells 24 h postirradiation). Lower doses of radiation (0.5 and 1 Gy) caused a transient delay in the G(2) phase of the cell cycle for the three cell lines but did not induce apoptosis (<5% apoptotic cells at 24 h postirradiation). Cells of all three cell lines died by apoptosis after exposure to 1 microg/ml nocodazole, a mitotic blocker that acts by inhibiting the polymerization of tubulin (>25% apoptotic cells after 24 h). When X irradiation with 4 or 6 Gy was performed at the time of addition of nocodazole to U698 and Daudi cells, X rays protected against the apoptosis-inducing effects of the microtubule inhibitor (<5% and 15% apoptotic cells, respectively, 24 h incubation). U698 and Daudi cells apparently have some error(s) in the signaling pathway inducing apoptosis after irradiation, and our results suggest that the arrest in G(2) prevents the cells from entering mitosis and from apoptosis in the presence of microtubule inhibitors. This arrest was overcome by caffeine, which caused U698 cells to enter mitosis (after irradiation) and become apoptotic in the presence of nocodazole (26% apoptotic cells, 24 h incubation). These results may have implications for the design of clinical multimodality protocols involving ionizing radiation for the treatment of cancer.     

Deltorphin II-induced rapid desensitization of delta-opioid receptor requires both phosphorylation and internalization of the receptor

Similar to other G protein-coupled receptors, rapid phosphorylation of the delta-opioid receptor in the presence of agonist has been reported. Hence, agonist-induced desensitization of the delta-opioid receptor has been suggested to be via the receptor phosphorylation, arrestin-mediated pathway. However, due to the highly efficient coupling between the delta-opioid receptor and the adenylyl cyclase, the direct correlation between the rates of receptor phosphorylation and receptor desensitization as measured by the adenylyl cyclase activity could not be established. In the current studies, using an ecdysone-inducible expression system to control the delta-opioid receptor levels in HEK293 cells, we could demonstrate that the rate of deltorphin II-induced receptor desensitization is dependent on the receptor level. Only at receptor concentrations 相似文献   

Hemodynamic Changes During Long Meditation

Changes in heart rate (HR) and blood pressure (BP) in advanced male meditators during 1 hr of meditation were compared with matched control participants resting for 1 hr. Also, changes in HR and BP during 3-hr meditation were analyzed. HR was recorded continuously during meditation (n = 38) and the control rest (n = 21). BP was measured before and after the meditation (n = 44) and the rest (n = 30). During the first hour, HR declined more in the meditators than the controls (p < .01). Within participant variability of HR was significantly lower during meditation than rest (p < .05). In the second hour of meditation, HR declined further (p = .01). BP was unaffected by either meditation or rest. In conclusion, meditation reduced the level of HR and within participant variability of HR more than rest. HR continued to decline during the second hour of meditation.     

Fertile House Ssparrow X Tree Sparrow (Passer domesticus XPasser montanus) hybrids?

Summary Viability and a seemingly successful breeding of a F1 House Sparrow x Tree Sparrow hybrid are reported from islands off the coast of northern Norway. From two consecutive clutches of House Sparrow x Tree Sparrow hybrids recorded in 1995, only one of 7 chicks survived the first year. The surviving individual was later, in 1997, found attending the nest with a female House Sparrow and feeding the young in two consecutive clutches. Neither of the F2 hybrids were observed after fledging. Despite the fact that House Sparrows indulge in frequent extra pair copulation, we find it unlikely that both clutches fed by the male hybrid could have been fathered by a House Sparrow male and therefore conclude that the F1 male hybrid was fertile. The hybridisation may have been facilitated by the fragmented structure and small size (from 5 to 100 individuals) of the sub-populations found in our study area.

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Fertile Haus- x Feldsperling (Passer domesticus X Passer montanus) Hybride?

Zusammenfassung Wir berichten über die Überlebensfähigkeit und einen offenbar erfolgreichen Brutversuch eines F1 Haussperling x Feldsperling Hybriden auf Inseln vor der nordnorwegischen Küste. Aus zwei aufeinanderfolgenden Gelegen eines gemischten Haus-/Feldsperling Paares, die wir 1995 beobachtet hatten, überlebte nur eines von sieben Jungtieren das erste Jahr. Das überlebende Individuum nistete später, 1997, mit einem Haussperlingweibchen und fütterte die Jungen zweier aufeinanderfolgender Bruten. Keiner der F2 Hybriden wurde nach dem Schlüpfen beobachtet. Obwohl bei Haussperlingen Kopulationen außerhalb des Paares häufig sind, betrachten wir es als unwahrscheinlich, daß beide vom männlichen Hybriden gefütterten Bruten von einem Haussperlingmännchen gezeugt worden waren. Wir schließen deshalb, daß das F1 Hybridmännchen fruchtbar war. Die Hybridisierung könnte durch die fragmentierte Struktur und die kleine Größe (5 bis 100 Individuen) der lokalen Populationen erleichtert worden sein.

     

Simvastatin Inhibits Glucose Metabolism and Legumain Activity in Human Myotubes

Simvastatin, a HMG-CoA reductase inhibitor, is prescribed worldwide to patients with hypercholesterolemia. Although simvastatin is well tolerated, side effects like myotoxicity are reported. The mechanism for statin-induced myotoxicity is still poorly understood. Reports have suggested impaired mitochondrial dysfunction as a contributor to the observed myotoxicity. In this regard, we wanted to study the effects of simvastatin on glucose metabolism and the activity of legumain, a cysteine protease. Legumain, being the only known asparaginyl endopeptidase, has caspase-like properties and is described to be involved in apoptosis. Recent evidences indicate a regulatory role of both glucose and statins on cysteine proteases in monocytes. Satellite cells were isolated from the Musculus obliquus internus abdominis of healthy human donors, proliferated and differentiated into polynuclear myotubes. Simvastatin with or without mevalonolactone, farnesyl pyrophosphate or geranylgeranyl pyrophosphate were introduced on day 5 of differentiation. After 48 h, cells were either harvested for immunoblotting, ELISA, cell viability assay, confocal imaging or enzyme activity analysis, or placed in a fuel handling system with [¹⁴C]glucose or [³H]deoxyglucose for uptake and oxidation studies. A dose-dependent decrease in both glucose uptake and oxidation were observed in mature myotubes after exposure to simvastatin in concentrations not influencing cell viability. In addition, simvastatin caused a decrease in maturation and activity of legumain. Dysregulation of glucose metabolism and decreased legumain activity by simvastatin points out new knowledge about the effects of statins on skeletal muscle, and may contribute to the understanding of the myotoxicity observed by statins.