Expansive arterial remodeling of the carotid arteries and its effect on atherosclerotic plaque composition and vulnerability: an in-vivo black-blood 3T CMR study in symptomatic stroke patients

Background: Based on intravascular ultrasound of the coronary arteries expansive arterial remodeling is supposed to be a feature of the vulnerable atheroslerotic plaque. However, till now little is known regarding the clinical impact of expansive remodeling of carotid lesions. Therefore, we sought to evaluate the correlation of expansive arterial remodeling of the carotid arteries with atherosclerotic plaque composition and vulnerability using in-vivo Cardiovascular Magnetic Resonance (CMR). Methods: One hundred eleven symptomatic patients (74 male/71.8 +/- 10.3y) with acute unilateral ischemic stroke and carotid plaques of at least 2 mm thickness were included. All patients received a dedicated multi-sequence black-blood carotid CMR (3Tesla) of the proximal internal carotid arteries (ICA). Measurements of lumen, wall, outer wall, hemorrhage, calcification and necrotic core were determined. Each vessel-segment was classified according to American Heart Association (AHA) criteria for vulnerable plaque. A modified remodeling index (mRI) was established by dividing the average outer vessel area of the ICA segments by the lumen area measured on TOF images in a not affected reference segment at the distal ipsilateral ICA. Correlations of mRI and clinical symptoms as well as plaque morphology/vessel dimensions were evaluated. Results: Seventy-eight percent (157/202) of all internal carotid arteries showed atherosclerotic disease with AHA Lesion-Type (LT) III or higher. The mRI of the ICA was significantly different in normal artery segments (AHA LT I;mRI 1.9) compared to atherosclerotic segments (AHA LT III-VII;mRI 2.5;p < 0.0001). Between AHA LT III-VII there was no significant difference of mRI. Significant correlations (p < 0.05) of the mRI with lumen-area (LA), wall-area (WA), vessel-area (VA) and wall-thickness (WT), necrotic-core area (NC), and ulcer-area were observed. With respect to clinical presentation (symptomatic/asymptomatic side) and luminal narrowing (stenotic/non-stenotic) no relevant correlations or significant differences regarding the mRI were found. Conclusion: Expansive arterial remodeling exists in the ICA. However, no significant association between expansive arterial remodeling, stroke symptoms, complicated AHA VI plaque, and luminal stenosis could be established. Hence, results of our study suggest that expansive arterial remodeling is not a very practical marker for plaque vulnerability in the carotid arteries

Poor performance of microbiological sampling in the prediction of recurrent arthroplasty infection

During a two-stage revision for prosthetic joint infections (PJI), joint aspirations, open tissue sampling and serum inflammatory markers are performed before re-implantation to exclude ongoing silent infection. We investigated the performance of these diagnostic procedures on the risk of recurrence of PJI among asymptomatic patients undergoing a two-stage revision. A total of 62 PJI were found in 58 patients. All patients had intra-operative surgical exploration during re-implantation, and 48 of them had intra-operative microbiological swabs. Additionally, 18 joint aspirations and one open biopsy were performed before second-stage reimplantation. Recurrence or persistence of PJI occurred in 12 cases with a mean delay of 218days after re-implantation, but only four pre- or intraoperative invasive joint samples had grown a pathogen in cultures. In at least seven recurrent PJIs (58%), patients had a normal C-reactive protein (CRP, <10mg/l) level before re-implantation. The sensitivity, specificity, positive predictive and negative predictive values of pre-operative invasive joint aspiration and CRP for the prediction of PJI recurrence was 0.58, 0.88, 0.5, 0.84 and 0.17, 0.81, 0.13, 0.86, respectively. As a conclusion, pre-operative joint aspiration, intraoperative bacterial sampling, surgical exploration and serum inflammatory markers are poor predictors of PJI recurrence. The onset of reinfection usually occurs far later than reimplantatio

Insight into Sulfur Confined in Ultramicroporous Carbon

Here, we provide a deeper insight into the state of sulfur confined in ultramicroporous carbon (UMC) and clarify its electrochemical reaction mechanism with lithium by corroborating the results obtained using various experimental techniques, such as X-ray photoelectron spectroscopy, electron energy loss spectroscopy, in situ Raman spectroscopy, and in situ electrochemical impedance spectroscopy. In combination, these results indicate that sulfur in UMC exists as linear polymeric sulfur rather than smaller allotropes. The electrochemical reactivity of lithium with sulfur confined in UMC (pore size ≤0.7 nm) is different from that of sulfur confined in microporous carbon (≤2 nm, or ultramicroporous carbon containing significant amount of micropores) and mesoporous carbon (>2 nm). The observed quasi-solid-state reaction of lithium with sulfur in UMC with a single voltage plateau during the discharge/charge process is due to the effective separation of solvent molecules from the active material. The size of carbon pores plays a vital role in determining the reaction path of lithium with sulfur confined in UMC

Medienbruchfreie Digitalisierung: Vom Gesetzestext zur digitalisierten Leistung in der öffentlichen Verwaltung

&lt;p&gt;This poster was presented in the context of the Poster Sessions of the &lt;a href="https://rvi23.de/"&gt;RVI2023&lt;/a&gt; conference.&lt;/p&gt;&lt;p&gt;This describes our vision of the end-to-end digitization of public administration in Germany.&lt;/p&gt

Comparison of symptomatic and asymptomatic atherosclerotic carotid plaques using parallel imaging and 3 T black-blood in vivo CMR

Background: To determine if black-blood 3 T cardiovascular magnetic resonance (bb-CMR) can depict differences between symptomatic and asymptomatic carotid atherosclerotic plaques in acute ischemic stroke patients. Methods: In this prospective monocentric observational study 34 patients (24 males; 70 +/- 9.3 years) with symptomatic carotid disease defined as ischemic brain lesions in one internal carotid artery territory on diffusion weighted images underwent a carotid bb-CMR at 3 T with fat-saturated pre- and post-contrast T1w-, PDw-, T2w- and TOF images using surface coils and Parallel Imaging techniques (PAT factor = 2) within 10 days after symptom onset. All patients underwent extensive clinical workup (lab, brain MR, duplex sonography, 24-hour ECG, transesophageal echocardiography) to exclude other causes of ischemic stroke. Prevalence of American Heart Association lesion type VI (AHA-LT6), status of the fibrous cap, presence of hemorrhage/thrombus and area measurements of calcification, necrotic core and hemorrhage were determined in both carotid arteries in consensus by two reviewers who were blinded to clinical information. McNemar and Wilcoxon's signed rank tests were use for statistical comparison. A p-value <0.05 was considered statistically significant. Results: Symptomatic plaques showed a higher prevalence of AHA-LT6 (67.7% vs. 11.8%; p < 0.001; odds ratio = 12.5), ruptured fibrous caps (44.1% vs. 2.9%; p < 0.001; odds ratio = 15.0), juxtaluminal thrombus (26.5 vs. 0%; < 0.01; odds ratio = 7.3) and intraplaque hemorrhage (58.6% vs. 11.8%; p = 0.01; odds ratio = 3.8). Necrotic core and hemorrhage areas were greater in symptomatic plaques (14.1 mm(2) vs. 5.5 mm(2) and 13.6 mm(2) vs. 5.3 mm(2); p < 0.01, respectively). Conclusion: 3 T bb-CMR is able to differentiate between symptomatic and asymptomatic carotid plaques, demonstrating the potential of bb-CMR to differentiate between stable and vulnerable lesions and ultimately to identify patients with low versus high risk for cardiovascular complications. Best predictors of the symptomatic side were a ruptured fibrous cap, AHA-LT 6, juxtaluminal hemorrhage/thrombus, and intraplaque hemorrhage

Erratum: Location of crossings in the Floquet spectrum of a driven two-level system (vol B 67, art no 165301, 2003)

Background: The purpose of this prospective study was to perform a head-to-head comparison of the two methods most frequently used for evaluation of carotid plaque characteristics: Multi-detector Computed Tomography Angiography (MDCTA) and black-blood 3 T-cardiovascular magnetic resonance (bb-CMR) with respect to their ability to identify symptomatic carotid plaques. Methods: 22 stroke unit patients with unilateral symptomatic carotid disease and > 50% stenosis by duplex ultrasound underwent MDCTA and bb-CMR (TOF, pre- and post-contrast fsT1w-, and fsT2w-sequences) within 15 days of symptom onset. Both symptomatic and contralateral asymptomatic sides were evaluated. By bb-CMR, plaque morphology, composition and prevalence of complicated AHA type VI lesions (AHA-LT6) were evaluated. By MDCTA, plaque type (non-calcified, mixed, calcified), plaque density in HU and presence of ulceration and/or thrombus were evaluated. Sensitivity (SE), specificity (SP), positive and negative predictive value (PPV, NPV) were calculated using a 2-by-2-table. Results: To distinguish between symptomatic and asymptomatic plaques AHA-LT6 was the best CMR variable and presence/absence of plaque ulceration was the best CT variable, resulting in a SE, SP, PPV and NPV of 80%, 80%, 80% and 80% for AHA-LT6 as assessed by bb-CMR and 40%, 95%, 89% and 61% for plaque ulceration as assessed by MDCTA. The combined SE, SP, PPV and NPV of bb-CMR and MDCTA was 85%, 75%, 77% and 83%, respectively. Conclusions: Bb-CMR is superior to MDCTA at identifying symptomatic carotid plaques, while MDCTA offers high specificity at the cost of low sensitivity. Results were only slightly improved over bb-CMR alone when combining both techniques

Dissociation of somatic growth, time of sexual maturity, and life expectancy by overexpression of an RGD-deficient IGFBP-2 variant in female transgenic mice

Impaired growth is often associated with an extension of lifespan. However, the negative correlation between somatic growth and life expectancy is only true within, but not between, species. This can be observed because smaller species have, as a rule, a shorter lifespan than larger species. In insects and worms, reduced reproductive development and increased fat storage are associated with prolonged lifespan. However, in mammals the relationship between the dynamics of reproductive development, fat metabolism, growth rate, and lifespan are less clear. To address this point, female transgenic mice that were overexpressing similar levels of either intact (D-mice) or mutant insulin-like growth factor-binding protein-2 (IGFBP-2) lacking the Arg-Gly-Asp (RGD) motif (E-mice) were investigated. Both lines of transgenic mice exhibited a similar degree of growth impairment (-9% and -10%) in comparison with wild-type controls (C-mice). While in D-mice, sexual maturation was found to be delayed and life expectancy was significantly increased in comparison with C-mice, these parameters were unaltered in E-mice in spite of their reduced growth rate. These observations indicate that the RGD-domain has a major influence on the pleiotropic effects of IGFBP-2 and suggest that somatic growth and time of sexual maturity or somatic growth and life expectancy are less closely related than thought previously