184 research outputs found
Die Auswandererberatungsstelle in MĂĽnster
Die Arbeit untersucht die Geschichte der Auswandererberatungsstelle in Münster von ihrer Gründung 1929 bis zu ihrer Schließung 1938. Einen besonderen Schwerpunkt legen die Autoren hierbei auf die Arbeitsweise der Beratungsstelle: Wer wurde hier beraten und wie und mit welchen Zielen liefen diese Beratungen ab? Nicht zuletzt fragt die Arbeit danach, ob jüdische Auswanderer von der Beratungsstelle als Sonderfälle behandelt wurden und wenn ja, ab wann
ANALYSIS AND LOCATION OF DEMAND SIDE INTEGRATION POTENTIALS IN URBAN SPACE USING GIS BASED DIGITAL CITY MAPS
ABSTRACT SCOPE AND APPROACH Scope The German energy turnaround is based on a massive growth in distributed renewable yet fluctuating electricity generation sources. This calls for a equally growing integration of flexible demand in order to be able to balance demand and generation in the transmission grid as well as in the "last mile" of certain distribution grid sections. In order to achieve this, questions about the Demand Side Integration (DSI) potential of different sectors as well as the precise location of these potentials in urban space are of growing importance. In this context a method to detect and map the DSI potential of HVAC within the urban space was developed and tested at the Center for Demand Side Integration of the University of Applied Sciences Hamburg in cooperation with the research group for computer-based methods in urban and regional planning at the Harbour City University in Hamburg. It was applied to a selected group of building usages of the tertiary sector and validated against results from a predecessor research project called "e-island" Approach Types of building usages taken into consideration The data set of the digital city map covers 339.094 buildings (total of Hamburg) with 128 possible different building usages. Since the DSI potential is highly dependent on the way of use of a building this data set was scaled down to all non-residential buildings from the tertiary sector having an "office-like" use. This limitation was applied because of the fact that for buildings like these distinct results about their DSI potential were available from the predecessor research project "E-Island". Assessment of energy reference areas and resulting energy uptake of the selected buildings Apart from the "office-like" usage only such buildings where considered that would have a significant energy demand. For the study it was presumed that only buildings with an annual energy demand of more than 100 MWh would have a DSI potential in HVAC that would be worth integrating in a virtual power plant or smart grid. Lacking the real figures of the energy consumption of th
Infective endocarditis caused by Pseudomonas stutzeri in a patient with Marfan syndrome: Case report and brief literature review
Invasive infections due to Pseudomonas stutzeri have rarely been described and mainly occur in immunocompromised individuals. We report a case of infective endocarditis caused by P. stutzeri after previous cardiac surgery in a Lebanese patient with Marfan syndrome. We review the literature and conclude that this pathogen may be of particular medical relevance in the Mediterranean Basin
Late-onset native valve endocarditis caused by Corynebacterium kroppenstedtii
Corynebacterium kroppenstedtii is an emerging cause of granulomatous mastitis and recurrent breast abscesses in women, but data on its clinical relevance in nongynecological disease conditions are limited. Here, we report the first case of a late-onset endocarditis of a native aortic valve in a 73-year-old male patient who presented with symptomatic aortic insufficiency. Echocardiography and cardiac computed tomography revealed the perforation of the noncoronary cusp and a large perivalvular abscess cavity. Hence, the surgical replacement of the aortic valve and aortic root were performed. Intraoperatively obtained tissue specimens grew C. kroppenstedtii and the patient made a full recovery after a 6-week course of antibiotic treatment. We briefly review the literature pertaining to antimicrobial susceptibility patterns of C. kroppenstedtii and available treatment recommendations. Our report calls for further studies to assess the role of this bacterium as a causative agent of infections other than granulomatous mastitis
Age-dependent phenotypic modulation of smooth muscle cells in the normal ascending aorta
Objectives: Ascending aortic aneurysms are associated with pre-existing conditions,
including connective tissue disorders (i.e., Marfan syndrome) and bicuspid aortic
valves. The underlying mechanisms remain uncertain. Even less is known regarding
ascending aortic aneurysms in individuals with normal (i.e., tricuspid) aortic valves
(TAV), and without known aneurysm-associated disorders. Regardless of etiology, the
risk of aortic complications increases with biological age. Phenotypic modulation of
smooth muscle cells (SMCs) is a feature of ascending aortic aneurysms, whereby
contractile SMCs are replaced with synthetic SMCs that are capable of degrading
the aortic wall. We asked whether age itself causes dysfunctional SMC phenotype
modulation, independent of aortic dilatation or pre-existing aneurysm-associated
diseases.
Methods: Non-dilated ascending aortic samples were obtained intra-operatively
from 40 patients undergoing aortic valve surgery (range: 20–82 years old, mean:
59.1 ± 15.2). Patients with known genetic diseases or aortic valve malformations were
excluded. Tissue was divided, and a portion was formalin-fixed and immunolabeled
for alpha-smooth muscle actin (ASMA), a contractile SMC protein, and markers of
synthetic (vimentin) or senescent (p16/p21) SMCs. Another fragment was used for
SMC isolation (n = 10). Cultured SMCs were fixed at cell passage 2 and stained for
phenotype markers, or were cultured indefinitely to determine replicative capacity.
Results: In whole tissue, ASMA decreased (R2 = 0.47, P < 0.0001), while vimentin
increased (R2 = 0.33, P = 0.02) with age. In cultured SMCs, ASMA decreased
(R2 = 0.35, P = 0.03) and vimentin increased (R2 = 0.25, P = 0.04) with age. p16
(R2 = 0.34, P = 0.02) and p21 (R2 = 0.29, P = 0.007) also increased with age in SMCs.
Furthermore, the replicative capacity of SMCs from older patients was decreased
compared to that of younger patients (P = 0.03).
Conclusion: By investigating non-dilated aortic samples from individuals with normal
TAVs, we found that age itself has a negative impact on SMCs in the ascending
aortic wall, whereby SMCs switched from the contractile phenotype to maladaptive
synthetic or senescent states with increased age. Therefore, based on our findings,
modification of SMC phenotype should be studied as a therapeutic consideration
against aneurysms in the future, regardless of etiology
Aortic regurgitation provokes phenotypic modulation of smooth muscle cells in the normal ascending aorta
Background: Aortic complications are more likely to occur in patients with
ascending aortic aneurysms and concomitant aortic regurgitation (AR). AR may
have a negative influence on the aortic wall structure even in patients with tricuspid
aortic valves and absence of aortic dilatation. It is unknown whether smooth muscle
cell (SMC) changes are a feature of AR-associated aortic remodeling.
Methods: Nondilated aortic samples were harvested intraoperatively from individuals with normal aortic valves (n ÂĽ 10) or those with either predominant aortic stenosis (AS) (n ÂĽ 20) or AR (n ÂĽ 35). Tissue from each patient was processed for
immunohistochemistry or used for the extraction of medial SMCs. Tissue and cells
were stained for markers of SMC contraction (alpha-smooth muscle actin), synthesis (vimentin) and senescence (p16INK4A and p21Cip1 [p16/p21]). Replicative capacity
was analyzed in cultured SMCs from AS- and AR-associated aortas. A subanalysis
compared SMCs from individuals with either tricuspid aortic valves or bicuspid
aortic valves to evaluate the effect of aortic valve morphology.
Results: In aortic tissue samples, AR was associated with decreased alpha-smooth
muscle actin and increased vimentin, p16 and p21 compared with normal aortic
valves and AS. In cell culture, SMCs from AR-aortas had decreased alpha-smooth
muscle actin and increased vimentin compared with SMCs from AS-aortas. ARassociated SMCs had increased p16 and p21 expression, and they reached
senescence earlier than SMCs from AS-aortas. In AR, SMC changes were more
pronounced with the presence of a bicuspid aortic valve.
Conclusions: AR itself negatively influences SMC phenotype in the ascending aortic
wall. This AR-specific effect is independent of aortic diameter and aortic valve
morphology, although it is more pronounced with bicuspid aortic valves. These
findings provide insight into the mechanisms of AR-related aortic remodeling,
and they provide a model for studying SMC-specific therapies in culture. (J Thorac
Cardiovasc Surg 2023;166:1604-16
The Ross procedure versus repair for treatment of a unicuspid aortic valve in adults
OBJECTIVES
Aortic stenosis or regurgitation in patients with a unicuspid valve morphology requires interventions early in life. We have performed either primary valve repair or the Ross procedure. The goal of this study was to compare the midterm results of repair and pulmonary autograft replacement.
METHODS
Between December 1998 and April 2022, a total of 345 patients (77% male; mean age 34 ± 9.7 years) underwent treatment of a unicuspid aortic valve. Patients were excluded if they were 54 years (n = 3) at the time of the operation. The remaining cohort was divided into 2 groups: 167 (64%) patients underwent valve repair; 91 (36%) patients underwent pulmonary autograft replacement.
The indications for surgery were aortic regurgitation (n = 104), aortic stenosis (n = 45), combined disease (n = 103) and endocarditis (n = 6). Fifty-one patients had root dilatation (>43 mm) with aortic regurgitation (repair n = 23; Ross n = 28). Mean follow-up was 5.9 years (SD: 5 years) [range 0.1–22.3 years].
RESULTS
There were 1 early and 3 late deaths; 47 patients required reintervention. Survival at 10 years was 95% in the Ross group and 97% after valve repair (P = 0.769). Freedom from reintervention at 10 years was 98% in the Ross group and 80% after valve repair (P = 0.012). A receiver operating characteristics curve analysis showed a trend towards better durability in patients < 26 years.
CONCLUSIONS
The ideal treatment of the unicuspid aortic valve remains debatable. Repair of a unicuspid valve can be considered a bridge to pulmonary autograft replacement, at least in younger patients. The appropriate times to replace and to repair require further investigation
Autograft reoperations after the Ross procedure
OBJECTIVES: After a Ross procedure, autograft failure can occur. At reoperation, repair of the autograft preserves the advantages of the
Ross procedure. The aim of this retrospective study was to assess mid-term results after reoperation of a failed autograft.
METHODS: Between 1997 and 2022, 30 consecutive patients (83% male; age 41 ± 11 years) underwent autograft reintervention between
60 days and 24 years (median 10 years) after a Ross procedure. The initial technique varied, full-root replacement (n = 25) being the most
frequent. The indication for reoperation was isolated autograft regurgitation (n = 7), root dilatation (>43 mm) with (n = 17) or without
(n = 2) autograft regurgitation, mixed dysfunction (n = 2) and endocarditis (n = 2). In 4 instances, the valve was replaced by valve (n = 1) or
combined valve and root replacement (n = 3). Valve-sparing procedures consisted of isolated valve repair (n = 7) or root replacement
(n = 19), and tubular aortic replacement. Cusp repair was performed in all but 2. Mean follow-up was 5.4 ± 6 years (35 days to 24 years).
RESULTS: Mean cross-clamp and perfusion times were 74 ± 26 and 132 ± 64 min. There were 2 perioperative deaths (7%; both valve replacement) and 2 patients died late (32 days to 1.2 years postoperatively). Freedom from cardiac death at 10 years was 96% after valve repair and 50% after replacement. Two patients required reoperation (1.68 and 16 years) following repair. One underwent valve replacement for cusp perforation, the other, root remodelling for dilatation. Freedom from autograft reintervention at 15 years was 95%.
CONCLUSIONS: Autograft reoperations after the Ross procedure can be performed as valve-sparing operations in the majority of cases.
With valve-sparing, long-term survival and freedom from reoperation are excellent
SMAD3 contributes to ascending aortic dilatation independent of transforming growth factor-beta in bicuspid and unicuspid aortic valve disease
We sought to determine whether there are differences in transforming growth factor-beta (TGFß) signaling in aneurysms associated with bicuspid (BAV) and unicuspid (UAV) aortic valves versus normal aortic valves. Ascending aortic aneurysms are frequently associated with BAV and UAV. The mechanisms are not yet clearly defined, but similarities to transforming growth factor-beta TGFß vasculopathies (i.e. Marfan, Loeys-Dietz syndromes) are reported. Non-dilated (ND) and aneurysmal (D) ascending aortic tissue was collected intra-operatively from individuals with a TAV (N = 10ND, 10D), BAV (N = 7ND, 8D) or UAV (N = 7ND, 8D). TGFß signaling and aortic remodeling were assessed through immuno-assays and histological analyses. TGFß1 was increased in BAV/UAV-ND aortas versus TAV (P = 0.02 and 0.04, respectively). Interestingly, TGFß1 increased with dilatation in TAV (P = 0.03) and decreased in BAV/UAV (P = 0.001). In TAV, SMAD2 and SMAD3 phosphorylation (pSMAD2, pSMAD3) increased with dilatation (all P = 0.04) and with TGFß1 concentration (P = 0.04 and 0.03). No relationship between TGFß1 and pSMAD2 or pSMAD3 was observed for BAV/UAV (all P > 0.05). pSMAD3 increased with dilatation in BAV/UAV aortas (P = 0.01), whereas no relationship with pSMAD2 was observed (P = 0.56). Elastin breaks increased with dilatation in all groups (all P < 0.05). In TAV, elastin degradation correlated with TGFß1, pSMAD2 and pSMAD3 (all P < 0.05), whereas in BAV and UAV aortas, elastin degradation correlated only with pSMAD3 (P = 0.0007). TGFß signaling through SMAD2/SMAD3 contributes to aortic remodeling in TAV, whereas TGFß-independent activation of SMAD3 may underlie aneurysm formation in BAV/UAV aortas. Therefore, SMAD3 should be further investigated as a therapeutic target against ascending aortic dilatation in general, and particularly in BAV/UAV patients
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