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OBJECTIVE: To test the hypothesis that IL-1beta and IL-6 play a pivotal role after myocardial infarction (MI) particularly in aged rats. METHODS: Chronic MI was induced in young adult (3.5 months) and aged (18 months) female Sprague-Dawley rats by ligation of the left coronary artery. Sham-operated animals of corresponding age served as controls. Heart function was measured by catheterization 4 weeks after MI. The expression of IL-1beta, IL-6, TGF-beta-isoforms, ANF, and components of the extracellular matrix (pro-collagen I and III, colligin, MMP-2 and TIMP2) was measured by ribonuclease protection assay. RESULTS: Aged control rats differed from young adult rats in that LV-developed pressure (LVDP) was higher (161 vs. 147 mmHg, p<0.05) in response to the elevated total peripheral resistance (0.71 vs. 0.47 mmHg ml min/kg, p<0.05). Contractility was reduced in aged controls as indicated by decreased LV dP/dt (8.106 vs. 10.606 mmHg/s, p<0.05). LV function was severely depressed in both MI groups (reduction in LVDP by about 35% and LV dP/dt by about 30%, increase in LVEDP to 24 mmHg) while RVP and RV dP/dt markedly increased by about 100%. This was not different between both MI groups. ANF expression as a marker of hypertrophy was induced in both MI groups, but less pronounced in the LV of aged rats. Also, the mRNA expression pattern was qualitatively comparable, but showed gradual differences. CONCLUSION: These results indicate that aged rats compensate well for hemodynamic overload induced by MI. Also, the mechanisms of myocardial post-MI remodeling are comparable in young adult and aged rats. 相似文献
43.
Markus Janczyk Roland Pfister Wilfried Kunde 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2013,231(1):97-106
Human–Computer Interactions pose special demands on the motor system, especially regarding the virtual tool transformations underlying typical mouse movements. We investigated whether such virtual tool-transformed movements are similarly resistant to irrelevant variation of a target object as skilled natural movements are. Results show that such irrelevant information deteriorates performance in perceptual tasks, whereas movement parameters remain unaffected, suggesting that the control of virtual tools draws on the same mechanisms as natural actions do. The results are discussed in terms of their practical utility and recent findings investigating unskilled and transformed movements in the framework of the action/perception model and the integration of tools into the body schema. 相似文献
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Michiels JJ Berghout A Schroyens W De Backer W Hoogsteden H Pattynama PM 《Seminars in vascular medicine》2002,2(4):345-351
Pulmonary angiography is the gold standard for diagnosis of segmental pulmonary embolism, but no longer for subsegmental pulmonary embolism because the inter-observer agreement for angiographically documented subsegmental pulmonary embolism is only 60%. A normal rapid ELISA VIDAS D-dimer test result and a normal perfusion scan exclude pulmonary embolism with a negative predictive value of >99%, irrespective of clinical score. The positive predictive value for pulmonary embolism of a high probability VP-scan compared to pulmonary angiography is 87% indicating that 13% of patients with a high probability VP-scan do not have pulmonary embolism. The combination of a negative CUS, a low clinical score, and a non-diagnostic VP-scan safely excludes pulmonary embolism. Patients with a non-diagnostic VP-scan, a negative CUS, but a moderate to high clinical score are candidates for pulmonary angiography. The positive predictive value of helical spiral CT is >95 to 99%. The combination of a negative CUS, a low clinical score, and the presence of a clear alternative diagnosis is predicted to safely exclude pulmonary embolism. Helical spiral CT detects all clinical relevant pulmonary emboli and a large number of alternative diagnoses in symptomatic patients with a non-diagnostic or a high-probability VP-scan. The negative predictive value during 3 months followup after a negative spiral CT for pulmonary embolism in 4 retrospective studies and 1 prospective management study was >99%. Only a small group of patients (1-2%) with a non-diagnostic spiral CT are candidates for pulmonary angiography. Therefore, it is predicted that the spiral CT will replace both VP-scanning and pulmonary angiography to safely exclude or diagnose pulmonary emboli in patients with suspected pulmonary embolism. 相似文献
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47.
Papanikolaou IS Adler A Wegener K Al-Abadi H Dürr A Koch M Pohl H Abou-Rebyeh H Veltzke-Schlieker W Wiedenmann B Rösch T 《European journal of gastroenterology & hepatology》2008,20(4):342-348
OBJECTIVES: Endoscopic ultrasonography (EUS) with the adjunct of EUS-guided fine needle aspiration has become an important diagnostic modality in gastroenterologic oncology. EUS-guided fine needle aspiration mainly relies on cytology; data are scarce that compare cytology and histology. While testing a 22-gauge prototype needle, we prospectively compared the yield for both. METHODS: Forty-two consecutive patients (27 male, 15 female; mean age 59.2 years, range: 17-90 years) were included. In each patient we aimed to make two needle passes, and if the material acquired appeared insufficient macroscopically (no in-room cytopathology was available), further passes were done. The material was sent for cytological and histological assessment. RESULTS: A median number of two passes (range: 2-3) were uneventfully performed for pancreatic lesions (n=30), mediastinal and other lymph nodes/masses (n=8) and various other lesions (n=4) and yielded adequate material for cytology, histology or at least one of the two investigations in 62, 67 and 74% of patients, respectively. No false positive results were found (specificity 100%). Sensitivities were 58.6 and 65.5%, respectively, for cytology and histology alone; combined assessment increased sensitivity to 79.3%. When adjusted values were calculated, based only on those cases with adequate material, sensitivity was 89.5% for cytology and 85.7% for histology, and increased to 100% with combined assessment. CONCLUSION: The new needle achieves sensitivities similar to those previously reported with no significant differences in sensitivity between cytology and histology. More effective tissue acquisition methods must be sought to improve overall results. 相似文献
48.
Ovidiu Chioncel John Parissis Alexandre Mebazaa Holger Thiele Steffen Desch Johann Bauersachs Veli‐Pekka Harjola Elena‐Laura Antohi Mattia Arrigo Tuvia B. Gal Jelena Celutkiene Sean P. Collins Daniel DeBacker Vlad A. Iliescu Ewa Jankowska Tiny Jaarsma Kalliopi Keramida Mitja Lainscak Lars H Lund Alexander R. Lyon Josep Masip Marco Metra Oscar Miro Andrea Mortara Christian Mueller Wilfried Mullens Maria Nikolaou Massimo Piepoli Susana Price Giuseppe Rosano Antoine Vieillard‐Baron Jean M. Weinstein Stefan D. Anker Gerasimos Filippatos Frank Ruschitzka Andrew J.S. Coats Petar Seferovic 《European journal of heart failure》2020,22(8):1315-1341
Cardiogenic shock (CS) is a complex multifactorial clinical syndrome with extremely high mortality, developing as a continuum, and progressing from the initial insult (underlying cause) to the subsequent occurrence of organ failure and death. There is a large spectrum of CS presentations resulting from the interaction between an acute cardiac insult and a patient's underlying cardiac and overall medical condition. Phenotyping patients with CS may have clinical impact on management because classification would support initiation of appropriate therapies. CS management should consider appropriate organization of the health care services, and therapies must be given to the appropriately selected patients, in a timely manner, whilst avoiding iatrogenic harm. Although several consensus‐driven algorithms have been proposed, CS management remains challenging and substantial investments in research and development have not yielded proof of efficacy and safety for most of the therapies tested, and outcome in this condition remains poor. Future studies should consider the identification of the new pathophysiological targets, and high‐quality translational research should facilitate incorporation of more targeted interventions in clinical research protocols, aimed to improve individual patient outcomes. Designing outcome clinical trials in CS remains particularly challenging in this critical and very costly scenario in cardiology, but information from these trials is imperiously needed to better inform the guidelines and clinical practice. The goal of this review is to summarize the current knowledge concerning the definition, epidemiology, underlying causes, pathophysiology and management of CS based on important lessons from clinical trials and registries, with a focus on improving in‐hospital management. 相似文献
49.
Verena Bröcker Muhannad Hirzallah Wilfried Gwinner Clemens Luitpold Bockmeyer Juliane Wittig Stephanie Zell Putri Andina Agustian Anke Schwarz Tina Ganzenmüller Eva Zilian Stephan Immenschuh Jan Ulrich Becker 《Virchows Archiv : an international journal of pathology》2014,464(2):203-211
According to the Banff guidelines for renal transplants, pure endothelialitis without any tubulointerstitial infiltrates (with the Banff components v?≥?1, i0, t0) has to be called acute cellular rejection (ACR). The pathophysiology of this rare lesion abbreviated as v_only is currently unclear, as well as its clinical, serological, and prognostic implications. Therefore, we conducted this retrospective comparative study. We compared all 23 biopsies with v_only from Hannover Medical School between 2003 and 2010 with 23 matched biopsies with the Banff components v?≥?1, i?≥?1, and t?≥?1 (v_plus) and 23 biopsies with v0, i0, and t0 (v0i0t0). Serological (available in 10, 11, and 14 patients, respectively), histological, and clinical data were compared. Of all biopsies, 0.4 % had findings of v_only. v_only, v_plus, and v0i0t0 only showed minimal differences in the Banff components apart from the cohort-defining components. Endothelialitis in v_only more frequently involved the arcuate arteries than the smaller preglomerular vessels compared to v_plus and vice versa. Combining histopathological data and serological data, v_only more frequently showed criteria for acute humoral rejection than v0i0t0 (albeit not persistent after the Bonferroni–Holm correction in pairwise comparisons), while there was no difference between v_only and v_plus. No difference could be demonstrated regarding clinical presentation at biopsy or outcome. Our results show minimal differences regarding clinical presentation, outcome, and histological features between v_only and v_plus. Patients with v_only should be thoroughly investigated for evidence of acute humoral rejection. 相似文献
50.
Florian Grahammer Nora Haenisch Frederic Steinhardt Lukas Sandner Malte Roerden Frederic Arnold Tomke Cordts Nicola Wanner Wilfried Reichardt Dontscho Kerjaschki Markus A. Ruegg Michael N. Hall Pierre Moulin Hauke Busch Melanie Boerries Gerd Walz Ferruh Artunc Tobias B. Huber 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(27):E2817-E2826