| 1. |
- Akiyama, Kazunori, et al.
(författare)
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First Sagittarius A* Event Horizon Telescope Results. V. Testing Astrophysical Models of the Galactic Center Black Hole
- 2022
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Ingår i: Astrophysical Journal Letters. - : American Astronomical Society. - 2041-8213 .- 2041-8205. ; 930:2
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Tidskriftsartikel (refereegranskat)abstract
- In this paper we provide a first physical interpretation for the Event Horizon Telescope's (EHT) 2017 observations of Sgr A*. Our main approach is to compare resolved EHT data at 230 GHz and unresolved non-EHT observations from radio to X-ray wavelengths to predictions from a library of models based on time-dependent general relativistic magnetohydrodynamics simulations, including aligned, tilted, and stellar-wind-fed simulations; radiative transfer is performed assuming both thermal and nonthermal electron distribution functions. We test the models against 11 constraints drawn from EHT 230 GHz data and observations at 86 GHz, 2.2 mu m, and in the X-ray. All models fail at least one constraint. Light-curve variability provides a particularly severe constraint, failing nearly all strongly magnetized (magnetically arrested disk (MAD)) models and a large fraction of weakly magnetized models. A number of models fail only the variability constraints. We identify a promising cluster of these models, which are MAD and have inclination i <= 30 degrees. They have accretion rate (5.2-9.5) x 10(-9) M (circle dot) yr(-1), bolometric luminosity (6.8-9.2) x 10(35) erg s(-1), and outflow power (1.3-4.8) x 10(38) erg s(-1). We also find that all models with i >= 70 degrees fail at least two constraints, as do all models with equal ion and electron temperature; exploratory, nonthermal model sets tend to have higher 2.2 mu m flux density; and the population of cold electrons is limited by X-ray constraints due to the risk of bremsstrahlung overproduction. Finally, we discuss physical and numerical limitations of the models, highlighting the possible importance of kinetic effects and duration of the simulations.
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| 2. |
- Jonkman, Nini H., et al.
(författare)
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Do self-management interventions work in patients with heart failure? An individual patient data meta-analysis
- 2016
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Ingår i: Circulation. - : Lippincott Williams & Wilkins. - 0009-7322 .- 1524-4539. ; 133:12, s. 1189-1198
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: -Self-management interventions are widely implemented in care for patients with heart failure (HF). Trials however show inconsistent results and whether specific patient groups respond differently is unknown. This individual patient data meta-analysis assessed the effectiveness of self-management interventions in HF patients and whether subgroups of patients respond differently.METHODS AND RESULTS: -Systematic literature search identified randomized trials of self-management interventions. Data of twenty studies, representing 5624 patients, were included and analyzed using mixed effects models and Cox proportional-hazard models including interaction terms. Self-management interventions reduced risk of time to the combined endpoint HF-related hospitalization or all-cause death (hazard ratio [HR], 0.80; 95% confidence interval [CI], 0.71-0.89), time to HF-related hospitalization (HR, 0.80; 95%CI, 0.69-0.92), and improved 12-month HF-related quality of life (standardized mean difference 0.15; 95%CI, 0.00-0.30). Subgroup analysis revealed a protective effect of self-management on number of HF-related hospital days in patients <65 years (mean number of days 0.70 days vs. 5.35 days; interaction p=0.03). Patients without depression did not show an effect of self-management on survival (HR for all-cause mortality, 0.86; 95%CI, 0.69-1.06), while in patients with moderate/severe depression self-management reduced survival (HR, 1.39; 95%CI, 1.06-1.83, interaction p=0.01).CONCLUSIONS: -This study shows that self-management interventions had a beneficial effect on time to HF-related hospitalization or all-cause death, HF-related hospitalization alone, and elicited a small increase in HF-related quality of life. The findings do not endorse limiting self-management interventions to subgroups of HF patients, but increased mortality in depressed patients warrants caution in applying self-management strategies in these patients.
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| 3. |
- de Boer, Rudolf A, et al.
(författare)
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Predictive value of plasma galectin-3 levels in heart failure with reduced and preserved ejection fraction
- 2011
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Ingår i: Annals of Medicine. - : Informa UK Limited. - 0785-3890 .- 1365-2060. ; 43:1, s. 60-68
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Tidskriftsartikel (refereegranskat)abstract
- AIMS: galectin-3 is an emerging biomarker which has been studied in relatively small heart failure (HF) cohorts with predominantly systolic HF. We studied the prognostic value of base-line galectin-3 in a large HF cohort, with preserved and reduced left ventricular ejection fraction (LVEF), and compared this to other biomarkers. METHODS: we studied 592 HF patients who had been hospitalized for HF and were followed for 18 months. The primary end-point was a composite of all-cause mortality and HF hospitalization. RESULTS: a doubling of galectin-3 levels was associated with a hazard ratio (HR) of 1.97 (1.62-2.42) for the primary outcome (P < 0.001). After correction for age, gender, BNP, eGFR, and diabetes the HR was 1.38 (1.07-1.78; P = 0.015). Galectin-3 levels were correlated with higher IL-6 and CRP levels (P < 0.002). Changes of galectin-3 levels after 6 months did not add prognostic information to the base-line value (n = 291); however, combining plasma galectin-3 and BNP levels increased prognostic value over either biomarker alone (ROC analysis, P < 0.05). The predictive value of galectin-3 was stronger in patients with preserved LVEF (n = 114) compared to patients with reduced LVEF (P < 0.001). CONCLUSIONS: galectin-3 is an independent marker for outcome in HF and appears to be particularly useful in HF patients with preserved LVEF.
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| 4. |
- Jaarsma, Tiny, et al.
(författare)
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Effect of moderate or intensive disease management program on outcome in patients with heart failure : Coordinating Study Evaluating Outcomes of Advising and Counseling in Heart Failure (COACH).
- 2008
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Ingår i: Archives of Internal Medicine. - : American Medical Association (AMA). - 0003-9926 .- 1538-3679. ; 168:3, s. 316-24
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Heart failure (HF) disease management programs are widely implemented, but data about their effect on outcome have been inconsistent. METHODS: The Coordinating Study Evaluating Outcomes of Advising and Counseling in Heart Failure (COACH) was a multicenter, randomized, controlled trial in which 1023 patients were enrolled after hospitalization because of HF. Patients were assigned to 1 of 3 groups: a control group (follow-up by a cardiologist) and 2 intervention groups with additional basic or intensive support by a nurse specializing in management of patients with HF. Patients were studied for 18 months. Primary end points were time to death or rehospitalization because of HF and the number of days lost to death or hospitalization. RESULTS: Mean patient age was 71 years; 38% were women; and 50% of patients had mild HF and 50% had moderate to severe HF. During the study, 411 patients (40%) were readmitted because of HF or died from any cause: 42% in the control group, and 41% and 38% in the basic and intensive support groups, respectively (hazard ratio, 0.96 and 0.93, respectively; P = .73 and P = .52, respectively). The number of days lost to death or hospitalization was 39 960 in the control group, 33 731 days for the basic intervention group (P = .81), and 34 268 for the intensive support group (P = .49). All-cause mortality occurred in 29% of patients in the control group, and there was a trend toward lower mortality in the intervention groups combined (hazard ratio, 0.85; 95% confidence interval, 0.66-1.08; P = .18). There were slightly more hospitalizations in the 2 intervention groups (basic intervention group, P = .89; and intensive support group, P = .60). CONCLUSIONS: Neither moderate nor intensive disease management by a nurse specializing in management of patients with HF reduced the combined end points of death and hospitalization because of HF compared with standard follow-up. There was a nonsignificant, potentially relevant reduction in mortality, accompanied by a slight increase in the number of short hospitalizations in both intervention groups. Clinical Trial Registry http://trialregister.nl Identifier: NCT 98675639.
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| 5. |
- Jonkman, Nini H., et al.
(författare)
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What Are Effective Program Characteristics of Self-Management Interventions in Patients With Heart Failure? : An Individual Patient Data Meta-analysis
- 2016
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Ingår i: Journal of Cardiac Failure. - : Elsevier BV. - 1071-9164 .- 1532-8414. ; 22:11, s. 861-871
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Tidskriftsartikel (refereegranskat)abstract
- Background To identify those characteristics of self-management interventions in patients with heart failure (HF) that are effective in influencing health-related quality of life, mortality, and hospitalizations.Methods and Results Randomized trials on self-management interventions conducted between January 1985 and June 2013 were identified and individual patient data were requested for meta-analysis. Generalized mixed effects models and Cox proportional hazard models including frailty terms were used to assess the relation between characteristics of interventions and health-related outcomes. Twenty randomized trials (5624 patients) were included. Longer intervention duration reduced mortality risk (hazard ratio 0.99, 95% confidence interval [CI] 0.97–0.999 per month increase in duration), risk of HF-related hospitalization (hazard ratio 0.98, 95% CI 0.96–0.99), and HF-related hospitalization at 6 months (risk ratio 0.96, 95% CI 0.92–0.995). Although results were not consistent across outcomes, interventions comprising standardized training of interventionists, peer contact, log keeping, or goal-setting skills appeared less effective than interventions without these characteristics.Conclusion No specific program characteristics were consistently associated with better effects of self-management interventions, but longer duration seemed to improve the effect of self-management interventions on several outcomes. Future research using factorial trial designs and process evaluations is needed to understand the working mechanism of specific program characteristics of self-management interventions in HF patients.
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| 6. |
- Lok, Dirk J., et al.
(författare)
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Prognostic value of N-terminal pro C-type natriuretic peptide in heart failure patients with preserved and reduced ejection fraction
- 2014
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Ingår i: European Journal of Heart Failure. - : Oxford University Press (OUP): Policy B / Wiley. - 1388-9842 .- 1879-0844. ; 16:9, s. 958-966
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Tidskriftsartikel (refereegranskat)abstract
- AimsA-type and B-type natriuretic peptides are established markers in chronic heart failure (HF). C-type natriuretic peptide (CNP) belongs to the same peptide family, but is predominantly localized in the endothelium. The prognostic role of CNP in heart failure has not been established. The aim of the study was to determine the prognostic power and clinical correlates of the N-terminal part of pro CNP (NT-proCNP) in patients with chronic HF. Methods and resultsIn 567 hospitalized heart failure patients, NT-proCNP levels were measured at hospital discharge. The primary endpoint was a combined endpoint of all-cause mortality and HF hospitalization after 18 months. Heart failure with a preserved ejection fraction (HFpEF) was pre-defined as an LVEF greater than40%. Mean (SD) age was 71 +/- 11years, 62% were male, mean LVEF was 32 +/- 14%, and 23% had HFpEF. In multivariate linear regression, NT-proCNP levels showed a positive correlation with NT-proBNP levels and parameters of renal function, whereas a negative correlation with female sex and vascular endothelial growth factor was observed. After 18 months follow-up, 240 patients reached the combined endpoint. We observed interaction between NT-proCNP and LVEF for outcome (P=0.046). Multivariate analyses revealed NT-proCNP to be strongly predictive for the primary endpoint [hazard ratio (HR) 1.78, 95% confidence interval (CI) 1.18-2.67, P=0.006) in patients with HFpEF, but not in patients with a reduced ejection fraction (HFrEF) (HR 1.07, 95% CI 0.81-1.43, P=0.616). Finally, reclassification showed significant additive value in patients with HFpEF (Pless than0.001), but not in those with HFrEF (P=0.453). Conclusionless thanp id="ejhf140-para-0003"greater thanNT-proCNP is a strong independent marker for outcome in patients with HFpEF, but not in those with HFrEF.
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| 7. |
- Luttik, Marie Louise A., et al.
(författare)
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Long-term follow-up in optimally treated and stable heart failure patients: primary care vs. heart failure clinic. Results of the COACH-2 study
- 2014
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Ingår i: European Journal of Heart Failure. - : Oxford University Press (OUP): Policy B / Wiley: 12 months. - 1388-9842 .- 1879-0844. ; 16:11, s. 1241-1248
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Tidskriftsartikel (refereegranskat)abstract
- AimsIt has been suggested that home-based heart failure (HF) management in primary care may be an alternative to clinic-based management in HF patients. However, little is known about adherence to HF guidelines and adherence to the medication regimen in these home-based programmes. The aim of the current study was to determine whether long-term follow-up and treatment in primary care is equally effective as follow-up at a specialized HF clinic in terms of guideline adherence and patient adherence, in HF patients initially managed and up-titrated to optimal treatment at a specialized HF clinic. Methods and resultsWe conducted a multicentre, randomized, controlled study in 189 HF patients (62% male, age 72 11 years), who were assigned to follow-up either in primary care (n = 97) or in a HF clinic (n = 92). After 12 months, no differences between guideline adherence, as estimated by the Guideline Adherence Indicator (GAI-3), and patient adherence, in terms of the medication possession ratio (MPR), were found between treatment groups. There was no difference in the number of deaths (n = 12 in primary care and n = 8 in the HF clinic; P = 0.48), and hospital readmissions for cardiovascular (CV) reasons were also similar. The total number of unplanned non-CV hospital readmissions, however, tended to be higher in the primary care group (n = 22) than in the HF clinic group (n = 10; P = 0.05). Conclusionsless thanp id="ejhf173-para-0003"greater thanPatients discharged after initial management in a specialized HF clinic can be discharged to primary care for long-term follow-up with regard to maintaining guideline adherence and patient adherence. However, the complexity of the HF syndrome and its associated co-morbidities requires continuous monitoring. Close collaboration between healthcare providers will be crucial in order to provide HF patients with optimal, integrated care.
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| 8. |
- Beal, Jacob, et al.
(författare)
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Robust estimation of bacterial cell count from optical density
- 2020
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Ingår i: Communications Biology. - : Springer Science and Business Media LLC. - 2399-3642. ; 3:1
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Tidskriftsartikel (refereegranskat)abstract
- Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data.
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