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81.
Nedim Selimovic Bert Andersson Claes‐Håkan Bergh Gunnar Mårtensson Folke Nilsson Odd Bech‐Hanssen Bengt Rundqvist 《Transplant international》2008,21(4):314-319
Lung transplantation (LTx) is a therapeutic option for patients with end-stage lung disease. However, the mortality rate of patients on the waiting list is high. The purpose of this study was to examine the prognostic value of cardio-pulmonary hemodynamics for death in patients awaiting LTx. Retrospectively, 177 patients with advanced lung disease accepted for LTx at Sahlgrenska University Hospital from January 1990 through December 2003 were studied. Patient demographics, pulmonary function tests, gas exchange and hemodynamic variables were included in the analysis. Death while awaiting LTx was the primary endpoint for all analyses. Mean age was 49 +/- 9 years. Main diagnoses were alpha 1 antitrypsin deficiency (n = 56), chronic obstructive pulmonary disease (n = 61), cystic fibrosis (n = 14) and interstitial lung disease (n = 46). Thirty patients died (17%). LTx was performed in 143 cases. By univariate analyses, forced vital capacity (FVC) % of predicted, pulmonary vascular resistance (PVR) and diagnosis were associated with risk for death. In multivariate analysis PVR (HR, 1.22; 95% CI, 1.06-1.41; P = 0.006) and FVC% of predicted (HR, 0.97; 95% CI, 0.94-0.99; P = 0.01) were independently associated with death. Patients with increased PVR and a lower FVC % of predicted awaiting LTx should be considered for a higher organ allocation priority. Assessment of pulmonary hemodynamics needs to be considered during evaluation for LTx. 相似文献
82.
S Otto M Seeber B Fujita D Kretzschmar M Ferrari B Goebel HR Figulla TC Poerner 《Basic research in cardiology》2012,107(5):289-12
Elevation of cardiac troponin I (cTnI) is a well-known complication after percutaneous coronary interventions (PCI). The aims of this study were to quantify the extent of coronary microembolization during elective PCI, to identify predisposing anatomical and procedural factors, and to evaluate its impact on long-term outcome in diabetic patients with a high cardiovascular risk. 48 patients (pts, median 66.7?years) with type 2 diabetes and coronary artery disease underwent elective PCI with stenting to treat single-vessel lesions. Real-time microembolization during PCI ("HITS") was detected by an intracoronary Doppler guide wire. Peak levels of cTnI were measured within 24?h after PCI. Pts were followed for 2?years to record major cardiac events (MACE: death, myocardial infarction, revascularization of target and non-target vessels). In 47 patients microemboli were detected during PCI. Nineteen patients showed pathologic cTnI elevation (0.13-28.9, median 0.39?μg/l). The amount of HITS correlated with cTnI levels (r?=?0.43, p?=?0.003), but not with other clinical or angiographic data. Within 2?years MACE were detected in 9 patients, who had significantly more microemboli (15.4?±?11.8 vs. 28.2?±?16.0 HITS; p?=?0.009, OR 1.07; 95?% CI 1.011-1.13) during PCI. HITS >23, but not cTnI elevation, predicted later MACE (ROC analysis, p?=?0.025). A high amount of microembolization during elective PCI in diabetic patients appears to be an indicator of greater atherosclerotic burden and accelerated coronary artery disease progression, associated with acute biomarker elevation and adverse long-term outcomes. 相似文献
83.
Hossam El‐Rewaidy Ulf Neisius Jennifer Mancio Selcuk Kucukseymen Jennifer Rodriguez Amanda Paskavitz Bjoern Menze Reza Nezafat 《NMR in biomedicine》2020,33(7)
Several deep‐learning models have been proposed to shorten MRI scan time. Prior deep‐learning models that utilize real‐valued kernels have limited capability to learn rich representations of complex MRI data. In this work, we utilize a complex‐valued convolutional network (?Net ) for fast reconstruction of highly under‐sampled MRI data and evaluate its ability to rapidly reconstruct 3D late gadolinium enhancement (LGE) data. ?Net preserves the complex nature and optimal combination of real and imaginary components of MRI data throughout the reconstruction process by utilizing complex‐valued convolution, novel radial batch normalization, and complex activation function layers in a U‐Net architecture. A prospectively under‐sampled 3D LGE cardiac MRI dataset of 219 patients (17 003 images) at acceleration rates R = 3 through R = 5 was used to evaluate ?Net . The dataset was further retrospectively under‐sampled to a maximum of R = 8 to simulate higher acceleration rates. We created three reconstructions of the 3D LGE dataset using (1) ?Net , (2) a compressed‐sensing‐based low‐dimensional‐structure self‐learning and thresholding algorithm (LOST), and (3) a real‐valued U‐Net (realNet) with the same number of parameters as ?Net . LOST‐reconstructed data were considered the reference for training and evaluation of all models. The reconstructed images were quantitatively evaluated using mean‐squared error (MSE) and the structural similarity index measure (SSIM), and subjectively evaluated by three independent readers. Quantitatively, ?Net ‐reconstructed images had significantly improved MSE and SSIM values compared with realNet (MSE, 0.077 versus 0.091; SSIM, 0.876 versus 0.733, respectively; p < 0.01). Subjective quality assessment showed that ?Net ‐reconstructed image quality was similar to that of compressed sensing and significantly better than that of realNet. ?Net reconstruction was also more than 300 times faster than compressed sensing. Retrospective under‐sampled images demonstrate the potential of ?Net at higher acceleration rates. ?Net enables fast reconstruction of highly accelerated 3D MRI with superior performance to real‐valued networks, and achieves faster reconstruction than compressed sensing. 相似文献
84.
N-terminal pro brain natriuretic peptide in arterial hypertension--a marker for left ventricular dimensions and prognosis 总被引:2,自引:0,他引:2
Hildebrandt P Boesen M Olsen M Wachtell K Groenning B 《European journal of heart failure》2004,6(3):313-317
In arterial hypertension risk factor evaluation, including LV mass measurements, and risk stratification using risk charts or programs, is generally recommended. In heart failure NT-proBNP has been shown to be a marker of LV dimensions and of prognosis. If the same diagnostic and prognostic value is present in arterial hypertension, risk factor evaluation would be easier. In 36 patients with arterial hypertension, electrocardiographic LV hypertrophy and preserved left ventricular function, NT-proBNP was eight-fold higher than in healthy subjects. The log NT-proBNP correlated with LV mass index (R=0.47, P=0.0002) measured by magnetic resonance imaging. In other subjects with arterial hypertension a significant but weak correlation to diastolic properties has been demonstrated. As for prognosis, a recent study in patients with hypertension, electrocardiographic left ventricular hypertrophy and preserved LV function demonstrated that NT-proBNP was a very strong prognostic marker, especially combined with a history of cardiovascular disease. Patients with high NT-proBNP and known cardiovascular disease had a seven-fold increase in CV events compared to patients with low NT-proBNP and no CV disease, while patients with either high NT-proBNP or CV disease had a three-four-fold increased risk. In conclusion NT-proBNP predicts LV mass in hypertensive patients and is a very strong prognostic marker in these patients. This could indicate a use of NT-proBNP in the future for risk stratification and perhaps monitoring of treatment in patients with arterial hypertension. 相似文献
85.
Alba Grifoni Swapnil Mahajan John Sidney Sheridan Martini Richard H. Scheuermann Bjoern Peters Alessandro Sette 《Human immunology》2019,80(11):923-929
Enteroviruses are potentially linked to the emergence of Acute Flaccid Myelitis (AFM), a rare but very serious condition that affects the nervous system. AFM has been associated with coxsackievirus A16, enterovirus A71 (EVA71) and enterovirus D68 (EVD68). Little is known about host-pathogen interactions for these viruses, and whether immune responses may have a protective or immunopathological role in disease presentations. Towards addressing this issue, we used the Immune Epitope Database to assess the known inventory of B and T cell epitopes from enteroviruses, focusing on data related to human hosts. The extent of conservation in areas that are targets of B and T cell immune responses were examined. This analysis sheds light on regions of the enterovirus polypeptide that can be probed to induce a specific or cross-reactive B or T cell the immune response to enteroviruses, with a particular focus on coxsackievirus A16, EVA71 and EVD68. In addition, these analyses reveal the current gap-of-knowledge in the T and B cell immune responses that future studies should aim to address. 相似文献
86.
Ioakimidis I Zandian M Ulbl F Bergh C Leon M Södersten P 《Physiology & behavior》2011,103(3-4):290-294
IOAKIMIDIS I, M. ZANDIAN, F. ULBL, C. BERGH, M LEON, AND P. S?DERSTEN. How eating affects mood. PHYSIOL BEHAV 2011 (000) 000-000. We hypothesize that the changes in mood that are associated with eating disorders are caused by a change in eating behavior. When food is in short supply, the rhythm of the neural network for eating, including orbitofrontal cortex and brainstem, slows down and we suggest that this type of neural activity activates a partially overlapping neural network for mood, including dorsal raphe serotonin projections to the orbitofrontal and prefrontal cortex. As a consequence, people who restrict the amount of food that they consume, either by choice or by their limited access to food, become preoccupied with food and food-related behavior. Most eating disorders emerge from a history of dietary restriction and we suggest that disordered eating consequent upon food restriction produces the altered mental state of patients with eating disorders. Based on the present hypothesis, eating disorders are not the result of a primary mental disorder. Rather, this notion suggests that the patients should be treated by learning to eat an appropriate amount of food at an appropriate rate. 相似文献
87.
Annick.F.L. Bogaerts Roland Devlieger Erik Nuyts Ingrid Witters Wilfried Gyselaers Isabelle Guelinckx Bea R.H. Van den Bergh 《Obesity facts》2013,6(2):152-164
BackgroundThe psychological health in obese women during pregnancy has been poorly studied.ObjectiveTo compare levels of anxiety and depressed mood during pregnancy in obese versus normal-weight women.Methods63 obese pregnant women and 156 normal-weight controls were included prospectively before 15 weeks of gestation. Levels of state and trait anxiety and depressed mood were measured during the first, second and third trimester of pregnancy. A linear mixed-effect model with repeated measures was used to evaluate group differences.ResultsThe levels of state anxiety significantly increased from trimester 1 to trimester 3 in obese pregnant women (beta = 3.70; p = 0.007), while this parameter remained constant throughout pregnancy in normal-weight women. Levels of trait anxiety and depressed mood significantly decreased from trimester 1 to trimester 2 in controls, but not in obese pregnant women. Variables such as maternal education, ethnicity, marital state, psychological history and miscarriages, parity and smoking behaviour had significant effects on anxiety and/or depressed moods during pregnancy. Obese pregnant women show higher levels of anxiety and depressive symptomatology compared to normal-weight pregnant women.ConclusionInterventional programmes aiming at preventing the deleterious influence of maternal obesity on perinatal outcomes should include a psycho-educational program specifically tailored to this high-risk group.Key Words: Obesity, Pregnancy, Body mass index, Anxiety, Depressed mood, Psychological aspects, Obesity management 相似文献
88.
Michael P. Lunn Peter Y. K. Van den Bergh 《Journal of the peripheral nervous system : JPNS》2015,20(3):255-259
Valid, responsive, and meaningful outcome measures for the measurement of the impairment, activity limitations, and quality of life in patients with neuromuscular disease are crucial to identify the natural history of disease and benefits of therapy in clinical practice and trials. Although understanding of many aspects of neuromuscular diseases has advanced dramatically, the development of outcome measures has received less attention. The scales developed from Rasch theory by the PeriNomS Group represent the biggest significant shift in thought in neuromuscular outcome measures for decades. There remain problems with many of them, and further developments are required. However, incorporating them into our outcome sets for daily use and in clinical trials will lead to the more efficient capture of meaningful change and will result in better assessment of individuals and groups of patients in both clinical trials and neurological practice. 相似文献
89.
Nerve conduction studies are an essential part of the work-up of peripheral neuropathies. Many neuropathic syndromes can be suspected on clinical grounds, but optimal use of nerve conduction study techniques (in combination with needle electromyography) allows diagnostic classification and is therefore crucial to understanding and separation of neuropathies. Multifocal motor neuropathy, for example, may clinically present as ALS. Detection of evidence of demyelination (conduction blocks) leads to the correct diagnosis and to proper treatment. Nerve conduction studies provide essential information on (1) the spatial pattern of neuropathy, (2) the pattern of abnormalities distinguishing between primarily axonal and demyelinating pathology, and (3) the severity of neuropathic damage. This information is very comprehensive since many nerves and long segments of individual nerves can be sampled. Moreover the information is extremely detailed to the extent that the cellular pathology of a patient's neuropathy is usually defined best by physiological testing rather than by biopsy. Neuropathies can be generalized, focal, or multifocal; they can be symmetric or asymmetric; they can be distally predominant or proximal and distal. Primarily axonal neuropathies mainly affect sensory nerve and compound muscle action potential amplitudes, whereas demyelinating neuropathies lead to slowing of nerve conductions, and to increased temporal dispersion or conduction block. Usually, the pattern of demyelination allows to distinguish hereditary (uniform demyelination) from acquired (segmental demyelination) neuropathies. Electrodiagnostic criteria for primary demyelination are helpful to identify acquired demyelinating neuropathies. 相似文献
90.
Blessing N. R. Jaja Daniel Attalla R. Loch Macdonald Tom A. Schweizer Michael D. Cusimano Nima Etminan Daniel Hanggi David Hasan S. Claiborne Johnston Peter Le Roux Benjamin Lo Ada Louffat-Olivares Stephan Mayer Andrew Molyneux Adam Noble Audrey Quinn Thomas Schenk Julian Spears Jeffrey Singh Michael Todd James Torner Ming Tseng William van den Bergh Mervyn D. I. Vergouwen George K. C. Wong 《Neurocritical care》2014,21(3):551-559
Researchers and other stakeholders continue to express concern about the failure of randomized clinical trials (RCT) in subarachnoid hemorrhage (SAH) to show efficacy of new treatments. Pooled data may be particularly useful to generate hypotheses about causes of poor outcomes and reasons for failure of RCT in SAH, and strategies to improve them. Investigators conducting SAH research collaborated to share data with the intent to develop a large repository of pooled individual patient data for exploratory analysis and testing of new hypotheses relevant to improved trial design and analysis in SAH. This repository currently contains information on 11,443 SAH patients from 14 clinical databases, of which 9 are datasets of recent RCTs and 5 are datasets of prospective observational studies and hospital registries. Most patients were managed in the last 15 years. Data validation and quality checks have been conducted and are satisfactory. Data is available on demographic, clinical, neuroimaging, and laboratory results and various outcome measures. We have compiled the largest known dataset of patients with SAH. The SAHIT repository may be an important resource for advancing clinical research in SAH and will benefit from contributions of additional datasets. 相似文献