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961.
Mona Salehi Ravesh Mohamed Salem Georg Lutter Christine Friedrich Veronika Walter Thomas Puehler Jochen Cremer Assad Haneya 《Journal of thoracic disease》2021,13(12):6769
BackgroundIt is controversial if the type or the size of aortic dissection is associated with the mortality in patients with acute aortic dissection (AAD) type I or type II according to DeBakey. Due to the pronounced aortic pathology in DeBakey type I compared to DeBakey type II, it is to be expected, that the DeBakey type I is associated with a significant higher morbidity and mortality. But we hypothesize that the current advances in surgical techniques, circulatory management, and postoperative care improve the clinical outcome of patients with DeBakey type I and II. The purpose of this study was to evaluate retrospectively the effect of these parameters on surgical outcome in patients with DeBakey type I and type II in a large cohort study.MethodsFrom 2001 to 2019, 395 consecutive patients (34.2% female) underwent surgical aortic repair at our institution. Patients were retrospectively classified into 2 groups: patients with type 1 dissection (group 1: n=309, median age of 62.0 years) and patients with type 2 dissection (group 2: n=86, 67.5 years). Survival was estimated by Kaplan-Meier estimator. Risk factors were analyzed by logistic regression analysis.ResultsThe patients in group 1 suffered significantly more often from coronary heart disease [43 (13.9%) vs. 20 (23.3%), P=0.036]. Otherwise, there were no significant differences between both groups concerning preoperative risk factors. The median surgical duration (279 vs. 263 min, P=0.026) and the circulatory arrest time (35 vs. 27 min, P<0.001) in group 1 were significantly higher. In a significantly higher number of patients in group 1, the aortic arch was completely replaced (18.4% vs. 1.2%, P<0.001) and a simultaneous coronary artery bypass grafting [18 (5.8%) vs. 11 (12.8%), P=0.028] was performed. The rate of re-thoracotomy [62 (20.1%) vs. 9 (10.5%), P=0.040], of postoperative delirium [66 (21.4%) vs. 9 (10.6%), P=0.024], and of tracheotomy [85 (27.5%) vs. 14 (16.3%), P=0.034] were significantly higher in group 1. Thirty-day mortality was 15.7% and did not differ significantly between both groups (P=0.867), as well as the long-term survival rates (P=0.956).ConclusionsDue to the pronounced aortic pathology in type I compared to type II, it is to be expected, that the type I is associated with a significant higher morbidity and mortality. DeBakey type I was an independent predictor for 30-day mortality in our study, however, based on our 17-year single center experience there was no difference between the long-term survival in both groups. 相似文献
962.
The immunopathogenesis of mycobacterial infections frequently involves the formation of caseating granulomas which cause tissue destruction and, in the case of tuberculosis (TB), may lead to cavity formation. Both intravenous and aerosol models of Mycobacterium tuberculosis infection in mice do not reflect the pulmonary lesions characteristic of TB patients. Using both low-dose (102 colony-forming units, cfu) and high-dose (105 cfu) aerosol infection with a highly virulent strain of Mycobacterium avium (TMC724) in C57BL/6 mice, it is now shown that these mice are capable of developing centrally caseating necrosis in lung granulomas after approximately 4 months of infection. In contrast, mice infected intravenously with the high dose never developed this type of lesion, although bacterial counts in their lungs reached levels comparable to those attained by aerosol-infected mice (1010 cfu). To study the relevance of events signalled by tumour necrosis factor (TNF) in this model, TNFRp55 gene-deficient and syngeneic C57BL/6 immunocompetent mice were infected with 105 cfu M. avium via aerosol. In gene-deficient mice, newly formed pulmonary granulomas acutely disintegrated, showing signs of apoptotic cell death and neutrophil influx, and TNFRp55 knock-out mice all succumbed to infection just beyond the stage of granuloma initiation. Aerogenic infection with M. avium in mice is a suitable model to study the immunopathogenesis of granuloma necrosis because it closely mimicks the histopathology of mycobacterial infections in humans, including TB. Furthermore, the use of TNFRp55 gene-deficient mice in this model establishes a role for TNF in maintaining the integrity of a developing pulmonary granuloma. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
963.
Stephanie Spranger Simone Schiller Anna Jauch Kathrin Wolff Inge Rauterberg-Ruland Dieter Hager Gholamali Tariverdian Jochen Trger Gudrun Rappold 《American journal of medical genetics. Part A》1999,83(5):367-371
We report on a mother and her 5-year old son, both with a terminal deletion of the short arm of the X chromosome. By molecular genetic analysis the breakpoint was located distal to steroid sulfatase gene. The boy manifested, due to nullisomy of this region, short stature (SHOX), chondrodysplasia punctata (ARSE), and mental retardation (putative mental retardation gene MRX 49). Short stature is present in mother and son, but both also had bilateral Madelung deformity, a key finding in the Léri-Weill syndrome.We discuss the phenotype in relationship to hitherto published cases with chromosomal aberrations and contiguous gene syndromes of Xp22.3. Am. J. Med. Genet. 83:367–371, 1999. © 1999 Wiley-Liss, Inc. 相似文献
964.
965.
We studied the characteristics of electrical coupling between Bergmann glial cells in mouse cerebellar slices using Lucifer Yellow injection, patch-clamping cell pairs, and ultrastructural inspection. While early postnatal cells (days 5–7) were not coupled, coupling was abundant at postnatal days 20–24. Coupled cells were arranged perpendicular to the parallel fibers in a parasagittal section, forming a string, rather than a cluster of cells. Electron microscopy revealed that gap junctions were abundant in the distal parts of the processes. Gap junctions between cell bodies and processes were very rare, and no gap junctions were found between cell bodies of adjacent Bergmann glial cells. The junctional conductance was voltage and time independent and could be markedly reduced by halothane. Alkalization of cells (by applying NH4+ increased the junctional conductance to 150%, while acidification of the cell interior (by removing NH4+) led to a decrease to 70%. Activation of AMPA receptors induced a blockade of the junctional conductance to 30% of the control. This link is most likely mediated by the influx of Ca2+ via the receptor since this effect was not observed in Ca2+-free medium, suggesting that Ca2+ entry via the kainate receptor pore led to the closure of gap junctions. These studies indicate that electrical coupling between Bergmann glial cells is not only developmentally regulated but also controlled by physiological stimuli. © 1996 Wiley-Liss, Inc. 相似文献
966.
967.
Vollmann J 《Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz》2008,51(8):865-871
This article provides a review on health care ethics committees and clinical ethics consultation in Germany. After a definition of these new institutions in the German health care system, detailed information on development, structures, implementation process and tasks of health care committees is provided. The three main tasks of health care ethics committees, clinical ethics consultation, development of ethical guidelines, and teaching and continuing medical education in clinical ethics are reported. Finally the author discusses the current professionalization and likely future developments of the field. 相似文献
968.
Jochen Klenk Clemens Becker Pierpaolo Palumbo Lars Schwickert Kilan Rapp Jorunn L. Helbostad Chris Todd Stephen R. Lord Ngaire Kerse 《Journal of the American Medical Directors Association》2017,18(11):921-927
Falls are a major cause of injury and disability in older people, leading to serious health and social consequences including fractures, poor quality of life, loss of independence, and institutionalization. To design and provide adequate prevention measures, accurate understanding and identification of person's individual fall risk is important. However, to date, the performance of fall risk models is weak compared with models estimating, for example, cardiovascular risk. This deficiency may result from 2 factors. First, current models consider risk factors to be stable for each person and not change over time, an assumption that does not reflect real-life experience. Second, current models do not consider the interplay of individual exposure including type of activity (eg, walking, undertaking transfers) and environmental risks (eg, lighting, floor conditions) in which activity is performed. Therefore, we posit a dynamic fall risk model consisting of intrinsic risk factors that vary over time and exposure (activity in context). eHealth sensor technology (eg, smartphones) begins to enable the continuous measurement of both the above factors. We illustrate our model with examples of real-world falls from the FARSEEING database. This dynamic framework for fall risk adds important aspects that may improve understanding of fall mechanisms, fall risk models, and the development of fall prevention interventions. 相似文献
969.
Kai Boelmans MD Jörn Kaufmann PhD Nils Bodammer PhD Georg Ebersbach MD Guido Behlau MSc Hans‐Jochen Heinze MD Ludwig Niehaus MD 《Movement disorders》2009,24(2):168-175
Corticobasal syndrome (CBS) is a progressive parkinsonian disease characterized by cortical and subcortical neuronal loss. Although motor disabilities are a core feature of CBS, the involvement of motor pathways in this condition has not been completely clarified. We used magnetic resonance diffusion tensor imaging (DTI) to study corticospinal and transcallosal motor projections in CBS, and applied fiber tractography to analyze the axonal integrity of white matter projections. Ten patients with CBS were compared with 10 age‐matched healthy controls. Fiber tracts were computed using a Monte‐Carlo simulation approach. Tract‐specific mean values of the apparent diffusion coefficient (ADC) and fractional anisotropy (FA) were determined. CBS patients showed a reduction of corticospinal tract (CST) fibers on the first affected side with significantly increased ADC and reduced FA values. In the corpus callosum (CC), particularly in the posterior trunk, patients also had significantly reduced fiber projections, with a higher ADC and lower FA than controls. This pattern indicates changes of the white matter integrity in both CST and CC. Thus, magnetic resonance DTI can be used to assess motor pathway involvement in CBS patients. © 2008 Movement Disorder Society 相似文献
970.
Potential impact of the sewer system on the applicability of alcohol and tobacco biomarkers in wastewater‐based epidemiology 下载免费PDF全文
Jochen F. Mueller Guangming Jiang Steve Carter Phong K. Thai 《Drug testing and analysis》2018,10(3):530-538
Understanding the actual consumption of alcohol and tobacco in the population is important for forming public health policy. For this purpose, wastewater‐based epidemiology has been applied as a complementary method to estimate the overall alcohol and tobacco consumption in different communities. However, the stability of their consumption biomarkers – ethyl sulfate, ethyl glucuronide, cotinine, and trans‐3′‐hydroxycotinine – in the sewer system has not yet been assessed. This study aimed to conduct such assessment using sewer reactors mimicking conditions of rising main, gravity sewer, and wastewater alone, over a 12‐hour period. The results show that cotinine and trans‐3′‐hydroxycotinine are relatively stable under all sewer conditions while ethyl sulfate was only stable in wastewater alone and gradually degraded in rising main and gravity sewer conditions. Ethyl glucuronide quickly degraded in all reactors. These findings suggest that cotinine and trans‐3′‐hydroxycotinine are good biomarkers to estimate tobacco consumption; ethyl sulfate may be used as a biomarker to estimate alcohol consumption, but its in‐sewer loss should be accounted for in the calculation of consumption estimates. Ethyl glucuronide, and probably most of glucuronide compounds, are not suitable biomarkers to be used in wastewater‐based epidemiology due to their in‐sewer instability. 相似文献