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While a rich literature addresses legislative agenda-setting in multiparty democracies, relatively little is known how members of parliament disseminate the legislative agenda beyond the parliamentary floor. Drawing on content analyses of 110 legislative debates and 5,847 press releases from Austrian MPs (2013-2017), we test whether legislators are more likely to send press releases on issues that are salient to their party ( party agenda-setting ) and to other parties in the party system ( systemic salience ). MPs should also communicate more on issues that fall within their area of expertise ( issue specialization ) and when they have given a speech on that issue during the legislative debate ( intra-party delegation ). While we find empirical support for all these expectations, communication of the legislative agenda largely rests on each parties' issue specialists and their speakers in plenary debates. Importantly, there is no significant discrepancy overall between the actual parliamentary issue agenda and the agenda communicated by party MPs., Competing Interests: Declaration of conflicting interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2020.)

Cytochrome P450s (P450s) comprise a superfamily of proteins that catalyze numerous monooxygenase reactions in animals, plants, and bacteria. In eukaryotic organisms, these proteins not only carry out reactions necessary for the metabolism of endogenous compounds, but they are also important in the oxidation of exogenous drugs and other foreign compounds. Eukaryotic P450 system proteins generally reside in membranes, primarily the endoplasmic reticulum or the mitochondrial membrane. These membranes provide a scaffold for the P450 system proteins that facilitate interactions with their redox partners as well as other P450s. This review focuses on the ability of specific lipid components to influence P450 activities, as well as the role of the membrane in P450 function. These studies have shown that P450s and NADPH-cytochrome P450 reductase appear to selectively associate with specific phospholipids and that these lipid-protein interactions influence P450 activities. Finally, because of the heterogeneous nature of the endoplasmic reticulum as well as other biologic membranes, the phospholipids are not arranged randomly but associate to generate lipid microdomains. Together, these characteristics can affect P450 function by 1) altering the conformation of the proteins, 2) influencing the P450 interactions with their redox partners, and 3) affecting the localization of the proteins into specific membrane microdomains., (Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.)

Cytochrome P450 (P450) function is dependent on the ability of these enzymes to successfully interact with their redox partners, NADPH-cytochrome P450 reductase (CPR) and cytochrome b5, in the endoplasmic reticulum (ER). Because the ER is heterogeneous in lipid composition, membrane microdomains with different characteristics are formed. Ordered microdomains are more tightly packed, and enriched in saturated fatty acids, sphingomyelin and cholesterol, whereas disordered regions contain higher levels of unsaturated fatty acids. The goal of the present study was to determine whether the P450 system proteins localize to different regions of the ER. The localization of CYP1A2, CYP2B4 and CYP2E1 within the ER was determined by partial membrane solubilization with Brij 98, centrifugation on a discontinuous sucrose gradient and immune blotting of the gradient fractions to identify ordered and disordered microdomains. CYP1A2 resided almost entirely in the ordered regions of the ER with CPR also localized predominantly to this region. CYP2B4 was equally distributed between the ordered and disordered domains. In contrast, CYP2E1 localized to the disordered membrane regions. Removal of cholesterol (an important constituent of ordered domains) led to the relocation of CYP1A2, CYP2B4 and CPR to the disordered regions. Interestingly, CYP1A1 and CYP1A2 localized to different membrane microdomains, despite their high degree of sequence similarity. These data demonstrate that P450 system enzymes are organized in specific membrane regions, and their localization can be affected by depletion of membrane cholesterol. The differential localization of different P450 in specific membrane regions may provide a novel mechanism for modulating P450 function.

Cytochrome P450 (P450) function requires the interaction of P450 and NADPH-cytochrome P450 reductase (CPR) in membranes, and is frequently studied using reconstituted systems composed solely of phosphatidylcholine. There is increasing evidence that other endoplasmic reticulum (ER) lipids can affect P450 structure, activity, and interactions with CPR. Some of these lipid effects have been attributed to the formation of organized liquid-ordered (l(o)) domains. The goal of this study was to determine if l(o) domains were formed in P450 reconstituted systems mimicking the ER membrane. CYP1A2, when incorporated in "ER-like" lipid vesicles, displayed detergent insolubility after treatment with Brij 98 and centrifugation in a sucrose gradient. Lipid probes were employed to identify domain formation in both ER-like vesicles and model membranes known to form l(o) domains. Changes in fluorescence resonance energy transfer (FRET) using an established donor/acceptor FRET pair in both ER-like and model l(o)-forming systems demonstrated the coexistence of l(o)- and liquid-disordered domains as a function of cholesterol and sphingomyelin content. Similarly, 6-dodecanoyl-2-dimethylaminonaphthalene (laurdan), a probe that reports on membrane organization, showed that cholesterol and sphingomyelin increased membrane order. Finally, brominated-phosphatidylcholine allowed for monitoring of the location of both CPR and CYP1A2 within the l(o) regions of ER-like systems. Taken together, the results demonstrate that ER-like vesicles generate microdomains, and both CYP1A2 and CPR predominantly localize into l(o) membrane regions. Probe fluorescent responses suggest that lipid microdomains form in these vesicles whether or not enzymes are included in the reconstituted systems. Thus, it does not appear that the proteins are critical for stabilizing l(o) domains.

Objective: We examined whether cognitive impairments or depressive symptoms impeded improvement in upper limb function in a clinical repetitive task practice program., Design: Participants had mild to moderate upper limb impairment after stroke (n = 20). We characterized baseline cognitive function and depressive symptoms using the Repeatable Battery of Neuropsychological Status and the Hamilton Rating Scale for Depression. We measured upper limb function at baseline, week 4, and week 24 using the Action Research Arm Test., Results: Participants with and without cognitive impairments improved significantly over time (F(1,17) = 84.48, P < 0.001) regardless of cognitive status (t(31) = 1.42, P = 0.16) or time since stroke (t(17) = 0.07, P = 0.95). Participants with and without depressive symptoms improved significantly over time (F(1,18) = 86.29, P < 0.001), but participants with depressive symptoms demonstrated greater improvement than did participants with no depressive symptoms (t(31) = 3.19, P = 0.003), regardless of time since stroke (t(17) = 0.06, P = 0.95)., Conclusions: Preliminary findings suggest that cognitive impairments and depressive symptoms may not impede benefit from repetitive task practice after stroke.

Objective: To determine whether onabotulinumtoxinA injections and task practice training with or without functional electrical stimulation (FES) improve upper limb motor function in chronic spastic hemiparesis., Design: Randomized controlled trial., Setting: Outpatient spasticity clinic., Participants: Participants (N=23) had chronic spastic hemiparesis with moderate-severe hand impairment based on Chedoke-McMaster Assessment greater than or equal to 2., Interventions: OnabotulinumtoxinA injections followed by 12 weeks of postinjection task practice. Participants randomly assigned to FES group were also fitted with an orthosis that provided FES., Main Outcome Measures: Motor Activity Log (MAL)-Observation was the primary outcome. Secondary outcomes were Action Research Arm Test (ARAT) and MAL-Self-Report., Results: For the entire cohort, MAL-Observation mean item scores improved significantly from baseline to week 6 (P=.005) but did not remain significant at week 12. MAL-Self-Report mean item scores improved significantly (P=.009) from baseline to week 6 and remained significantly higher (P=.014) at week 12. ARAT total scores also improved significantly from baseline to week 6 (P=.018) and were sustained at week 12 (P=.032). However, there were no significant differences between the FES and no-FES groups for any outcome variable over time., Conclusions: Rehabilitation strategies that combine onabotulinumtoxinA injections and task practice therapy are feasible and effective in improving upper-limb motor function and reducing spasticity in patients with chronic spastic hemiparesis. However, the cyclic FES protocol used in this study did not increase gains achieved with the combination of onabotulinumtoxinA and task practice alone.

Objective: To determine whether baseline hand spastic hemiparesis assessed by the Chedoke-McMaster Assessment influences functional improvement after botulinum toxin type A (BTX-A) injections and postinjection therapy., Design: Prospective cohort study., Setting: Outpatient spasticity clinic., Participants: Participants (N=14) with spastic hemiparesis divided into 2 groups: Chedoke-McMaster Assessment Hand-Higher Function (stage> or =4, n=5) and Chedoke-McMaster Assessment Hand-Lower Function (stage=2 or 3, n=9)., Interventions: Upper-limb BTX-A injections followed by 6 weeks of postinjection therapy., Main Outcome Measures: Primary outcomes were Motor Activity Log-28 and Motor Activity Log items. Secondary outcomes were Action Research Arm Test (ARAT), Motor Activity Log-Self-Report, and Modified Ashworth Scale (MAS). Measures were assessed at baseline (preinjection), 6 weeks, 9 weeks, and 12 weeks postinjection., Results: Primary and secondary outcomes improved significantly over time in both groups. Although no significant differences in ARAT or MAS change scores were noted between groups, Chedoke-McMaster Assessment Hand-Higher Function group demonstrated greater change on Motor Activity Log-28 (P=.013) from baseline to 6 weeks and Motor Activity Log items (P=.006) from baseline to 12 weeks compared to Chedoke-McMaster Assessment Hand-Lower Function group., Conclusions: BTX-A injections and postinjection therapy improved hand function and reduced spasticity for both Chedoke-McMaster Assessment Hand-Higher Function and Chedoke-McMaster Assessment Hand-Lower Function groups. Clinicians should expect to see larger gains for persons with less baseline impairment.

In recent studies, it has been shown that mixtures of palmitic acid (PA), and cholesterol or cholesterol sulfate (Schol), in a PA/sterol molar ratio of 30/70 lead to the formation of liquid-ordered (lo) lamellar phases. The extrusion of these systems gave large unilamellar vesicles (LUVs) that displayed a very limited passive permeability, a property associated with their high sterol content. In this study, we showed that the formation of lo-phase bilayers was also possible when mixing a cationic detergent (cetylpyridinium chloride, CPC) and sterol in a 30/70 molar ratio. The existence of this phase was established using IR and 2H NMR spectroscopy. Moreover, 2H NMR allowed us to study the orientation and dynamics of CPC and cholesterol in these self-assemblies. The extrusion of the CPC/Schol bilayers leads to the formation of LUVs, and their passive permeability was found to be very limited, making them interesting candidates as nanovectors.

In a previous study from our laboratory (Drug Metab Dispos 34: 660-666, 2006), we found several limitations with published methods (cholate gel filtration and cholate dialysis) for the incorporation of cytochromes P450 and P450 reductase into phospholipid vesicles. We found that a significant proportion of reductase was not incorporated in the vesicles when the amount of reductase was equal to or greater than that of CYP2B4 in the systems reconstituted with phosphatidylcholine. Furthermore, implementation of these methods compromised the ability of the CYP2B4 to form a ferrous carbon monoxy complex. In the current study, a comparison of results using the detergent-dialysis method with five similar detergents having the "bile salt" ring structure showed that glycocholate results in the greatest incorporation of reductase and the least loss in the ferrous carbon monoxy CYP2B4 complex. The method is further improved by using Bio-Beads SM-2 to remove detergent instead of the lengthy dialysis procedure or size exclusion chromatography that significantly dilutes the protein and lipid concentrations of the preparation. The method is shown to be applicable over a range of lipid/CYP2B4 ratios, and by using assay methods for total lipid, reductase, and CYP2B4, this improved reconstitution method resulted in increased incorporation efficiencies while minimizing the protein degradation inherent with these procedures.

Objectives: Pericardial effusion occurs frequently after orthotopic heart transplantation, but the causes of this complication have not been well described. This study was designed to identify factors predisposing toward the development of significant postoperative pericardial effusions in a large, single-institution population of orthotopic heart transplant recipients., Methods: A retrospective review of more than 90 preoperative, intraoperative, and postoperative variables was conducted for 241 patients undergoing orthotopic heart transplantation from September 1988 to December 1999. Patients who had significant postoperative pericardial effusions develop were identified from postoperative echocardiograms by standard criteria. Factors associated with the development of significant pericardial effusions were determined by multivariate logistic regression analysis., Results: Echocardiographic data were available for 203 of 241 transplant recipients. Forty-two patients (21%) had significant effusions develop. According to multivariate analysis, pericardial effusions were less likely to occur in recipients with a history of previous cardiac surgery (odds ratio 0.13, 95% confidence interval 0.05-0.36, P <.0001) and with greater weight (odds ratio 0.96, 95% confidence interval 0.94-0.99, P <.0048). Pericardial effusions were more likely to occur in patients who had received aminocaproic acid during the operation (odds ratio 5.92, 95% confidence interval 2.23-15.72, P <.0008). Patient survival and hospital length of stay did not differ between patients with and without postoperative pericardial effusions., Conclusions: Postoperative pericardial effusions develop in approximately 20% of patients undergoing orthotopic cardiac transplantation. On the basis of the risk factors identified in this study, prevention may prove difficult, although avoidance of the intraoperative use of aminocaproic acid may be helpful.

Background: Cardiac output is often monitored after cardiac operations with a pulmonary artery catheter. A new method has been introduced that measures cardiac output by lithium dilution (LiDCO) and uses these data to calibrate a system (PulseCO) that calculates cardiac output continuously from the energy of the arterial pressure waveform. It is unknown whether PulseCO measurements are valid early after cardiac surgery when changes in temperature and vascular tone or intermittent use of the arterial line for blood sampling may occur. This study assessed the reliability of cardiac output determinations by PulseCO in the first 8 hours after cardiac surgery., Methods: After a one-time PulseCO calibration, cardiac output was measured in 20 patients who had undergone coronary artery bypass grafting at 0, 2, 4, 6, and 8 hours after arrival in the intensive care unit using (1) thermodilution through a pulmonary artery catheter (Thermo); (2) lithium dilution (LiDCO); and (3) PulseCO. Concordance correlations were calculated between methods, and differences were compared by Wilcoxon paired rank test and Bland-Altman analysis., Results: Cardiac output ranged from 3.4 to 8.5 L/min. No significant differences were noted between measurements obtained by each technique at any time point. Concordance correlations and Bland-Altman analysis confirmed good agreement between PulseCO and Thermo determinations of cardiac output during the study interval., Conclusions: PulseCO measurements remain reliable without recalibration for at least 8 hours after cardiac surgery and may offer a less-invasive approach for early postoperative cardiac output monitoring.