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101.
Any physician treating cardiac arrhythmias should be aware of a possible worsening of the arrhythmia (so-called arrhythmogenesis) after the start of antiarrhythmic drug treatment. To facilitate the recognition of that complication the type and possible mechanisms of arrhythmogenesis are reviewed. Recognition also requires an understanding of (a) the time of appearance of arrhythmogenic effects after different drugs, (b) the value of non-invasive and invasive tests, and (c) the profile of the patient most likely to develop this problem. Guidelines are given to reduce the incidence of the arrhythmogenic effects of antiarrhythmic drugs and a plea is made that the physician should be always on the alert for this complication. 相似文献
102.
Vos MH Borisov VB Liebl U Martin JL Konstantinov AA 《Proceedings of the National Academy of Sciences of the United States of America》2000,97(4):1554-1559
Interaction of the two high-spin hemes in the oxygen reduction site of the bd-type quinol oxidase from Escherichia coli has been studied by femtosecond multicolor transient absorption spectroscopy. The previously unidentified Soret band of ferrous heme b(595) was determined to be centered around 440 nm by selective excitation of the fully reduced unliganded or CO-bound cytochrome bd in the alpha-band of heme b(595). The redox state of the b-type hemes strongly affects both the line shape and the kinetics of the absorption changes induced by photodissociation of CO from heme d. In the reduced enzyme, CO photodissociation from heme d perturbs the spectrum of ferrous cytochrome b(595) within a few ps, pointing to a direct interaction between hemes b(595) and d. Whereas in the reduced enzyme no heme d-CO geminate recombination is observed, in the mixed-valence CO-liganded complex with heme b(595) initially oxidized, a significant part of photodissociated CO does not leave the protein and recombines with heme d within a few hundred ps. This caging effect may indicate that ferrous heme b(595) provides a transient binding site for carbon monoxide within one of the routes by which the dissociated ligand leaves the protein. Taken together, the data indicate physical proximity of the hemes d and b(595) and corroborate the possibility of a functional cooperation between the two hemes in the dioxygen-reducing center of cytochrome bd. 相似文献
103.
Jurren M. van Opstal S. Cora Verduyn Stephan K. G. Winckels Hendrik M. Leerssen Jet D. M. Leunissen Hein J. J. Wellens Marc A. Vos 《Journal of interventional cardiac electrophysiology》2002,6(2):113-120
Heterogeneity in cardiac repolarization (APD) is known to be arrhythmic. In the dog model of chronic complete AV-block and acquired long QT syndrome, an increase in MAPD (defined as left ventricular monophasic action potential duration (MAPD) minus right ventricular MAPD) is often associated with changes in T-wave morphology. The purpose of this study was to correlate known changes in MAPD with the planimetric total area of the T-wave on the surface ECG (JT,mV · ms).
Methods: The relationship between MAPD and total area of the T-wave (i.e., JT-area) was assessed in four different protocols with different types of dispersion: (1) class III drugs followed by levcromakalim (n = 7), (2) LAD coronary artery occlusion and reperfusion (n = 6), (3) dronedarone i.v., an amiodarone like agent (n = 5) and (4) steady state pacing at cycle lengths of 1000 ms and 500 ms (n = 5).
Results: Class III drugs increased MAPD (55 ± 40 ms to 120 ± 50 ms#, P < 0.05), which was correlated (r = 0.74, P < 0.001) with JT-area (50 ± 40 mV · ms to 95 ± 35 mV · ms#). Ischemia increased both MAPD (30 ± 25 ms to 90 ± 40 ms#) and JT-area (60 ± 55 mV · ms to 75 ± 50 mV · ms#). Both levcromakalim and reperfusion reversed these conditions. Dronedarone had no effect on MAPD or on JT-area while a faster frequency reduced both MAPD and JT-area.
Conclusion: Changes in dispersion of ventricular repolarization are reflected by alterations in JT-area. This non-invasive parameter may therefore be used to indicate changes in heterogeneity in ventricular repolarization. 相似文献
104.
Vrieze A Van Nood E Holleman F Salojärvi J Kootte RS Bartelsman JF Dallinga-Thie GM Ackermans MT Serlie MJ Oozeer R Derrien M Druesne A Van Hylckama Vlieg JE Bloks VW Groen AK Heilig HG Zoetendal EG Stroes ES de Vos WM Hoekstra JB Nieuwdorp M 《Gastroenterology》2012,143(4):913-916.e7
Alterations in intestinal microbiota are associated with obesity and insulin resistance. We studied the effects of infusing intestinal microbiota from lean donors to male recipients with metabolic syndrome on the recipients' microbiota composition and glucose metabolism. Subjects were assigned randomly to groups that were given small intestinal infusions of allogenic or autologous microbiota. Six weeks after infusion of microbiota from lean donors, insulin sensitivity of recipients increased (median rate of glucose disappearance changed from 26.2 to 45.3 μmol/kg/min; P < .05) along with levels of butyrate-producing intestinal microbiota. Intestinal microbiota might be developed as therapeutic agents to increase insulin sensitivity in humans; www.trialregister.nl; registered at the Dutch Trial Register (NTR1776). 相似文献
105.
106.
Bram Jacobs Tjemme Beems Ton M. van der Vliet Arie B. van Vugt Cornelia Hoedemaekers Janneke Horn Gaby Franschman Ian Haitsma Joukje van der Naalt Teuntje M. J. C. Andriessen George F. Borm Pieter E. Vos 《Neurocritical care》2013,19(1):79-89
Background
With this study we aimed to design validated outcome prediction models in moderate and severe traumatic brain injury (TBI) using demographic, clinical, and radiological parameters.Methods
Seven hundred consecutive moderate or severe TBI patients were included in this observational prospective cohort study. After inclusion, clinical data were collected, initial head computed tomography (CT) scans were rated, and at 6 months outcome was determined using the extended Glasgow Outcome Scale. Multivariate binary logistic regression analysis was applied to evaluate the association between potential predictors and three different outcome endpoints. The prognostic models that resulted were externally validated in a national Dutch TBI cohort.Results
In line with previous literature we identified age, pupil responses, Glasgow Coma Scale score and the occurrence of a hypotensive episode post-injury as predictors. Furthermore, several CT characteristics were associated with outcome; the aspect of the ambient cisterns being the most powerful. After external validation using Receiver Operating Characteristic (ROC) analysis our prediction models demonstrated adequate discriminative values, quantified by the area under the ROC curve, of 0.86 for death versus survival and 0.83 for unfavorable versus favorable outcome. Discriminative power was less for unfavorable outcome in survivors: 0.69.Conclusions
Outcome prediction in moderate and severe TBI might be improved using the models that were designed in this study. However, conventional demographic, clinical and CT variables proved insufficient to predict disability in surviving patients. The information that can be derived from our prediction rules is important for the selection and stratification of patients recruited into clinical TBI trials. 相似文献107.
B. de Vos J. Hendriks P. Van Schil R. Van Hee L. Hendrickx 《Acta chirurgica Belgica》2013,113(6):439-444
Objective: Analysis of the long-term results of video-assisted thoracic surgery (VATS) for spontaneous pneumothorax in patients treated in two surgical centres from May 1994 until December 2000.Methods: A cohort of 86 patients was studied retrospectively. For final analysis, 74 patients undergoing 76 VATS procedures were included.Results: Sixty-three procedures for primary spontaneous pneumothorax (PSP) and 13 procedures for secondary spontaneous pneumothorax (SSP) were performed. In 78.9% (n = 60) blebs or bullae were resected with an endostapler device. In 2.6% (n = 2) an apical fibrotic zone was resected. In 71.1% (n = 54) a subtotal pleurectomy was performed combined with an abrasion in 41 cases. In 21.1% (n = 16) a total pleurectomy and in 7.8% (n = 6) an abrasion was performed. Operative mortality was 1.3% (n = 1) and total operative morbidity 25.4% in the PSP group and 76.9% in the SSP group. Mean follow-up was 36 months. The global recurrence rate was 5.3% (n = 4), being 4.8% (n = 3) in the PSP group and 7.7% (n = 1) in the SSP group. Recurrences occurred at 1 (n = 2), 2 (n = 1) and 16 (n = 1) months after the initial operation. The incidence of postoperative neuralgia was 17.1% (n = 13). One patient needed analgesics for the neuralgia.Conclusion: VATS treatment of spontaneous pneumothorax proves to be effective. In cases of SSP, VATS treatment is feasible but a higher morbidity rate should be anticipated. 相似文献
108.
C.G. Vos K.J. Hartemink S. Muller J. W. A. Oosterhuis S. Meijer M. Petrousjka van den Tol 《Acta chirurgica Belgica》2013,113(6):414-418
Background : For a definitive diagnosis in many oncological, inflammatory and infectious diseases histological examination is required. Non-palpable lesions detected with PET/CT scanning that cannot be localized with conventional imaging methods can be localized and excised using FDG-probe guided surgery. We describe the application of FDG-probe guided surgery in 9 patients.Methods : The application of FDG-probe guided surgery used in 9 consecutive patients with oncological and infectious diseases is described. Four hours before surgery, 3.5 MBq/Kg body weight FDG was intravenously administered after which a FDG-PET-scan was performed to confirm the FDG-avid lesion(s). The lesions with highest activity were detected with the FDG-probe and the lesions were subsequently excised and sent for histopathological examination. Results : In all of the 9 cases the target lesion was successfully identified and subsequently removed. When multiple and/or macroscopically normal lymph nodes were found, the use of the FDG-probe allowed selection of the PET-avid lymph nodes for resection.Conclusion : FDG-probe guided surgery is a relatively simple surgical technique to identify and excise FDG-accumu-lating suspicious lesions in oncological, inflammatory and infectious diseases. 相似文献
109.
Fiona?J?CharlsonEmail author Andrew?E?Moran Greg?Freedman Rosana?E?Norman Nicolas?JC?Stapelberg Amanda?J?Baxter Theo?Vos Harvey?A?Whiteford 《BMC medicine》2013,11(1):250
Background
Cardiovascular disease and mental health both hold enormous public health importance, both ranking highly in results of the recent Global Burden of Disease Study 2010 (GBD 2010). For the first time, the GBD 2010 has systematically and quantitatively assessed major depression as an independent risk factor for the development of ischemic heart disease (IHD) using comparative risk assessment methodology.Methods
A pooled relative risk (RR) was calculated from studies identified through a systematic review with strict inclusion criteria designed to provide evidence of independent risk factor status. Accepted case definitions of depression include diagnosis by a clinician or by non-clinician raters adhering to Diagnostic and Statistical Manual of Mental Disorders (DSM) or International Classification of Diseases (ICD) classifications. We therefore refer to the exposure in this paper as major depression as opposed to the DSM-IV category of major depressive disorder (MDD). The population attributable fraction (PAF) was calculated using the pooled RR estimate. Attributable burden was calculated by multiplying the PAF by the underlying burden of IHD estimated as part of GBD 2010.Results
The pooled relative risk of developing IHD in those with major depression was 1.56 (95% CI 1.30 to 1.87). Globally there were almost 4 million estimated IHD disability-adjusted life years (DALYs), which can be attributed to major depression in 2010; 3.5 million years of life lost and 250,000 years of life lived with a disability. These findings highlight a previously underestimated mortality component of the burden of major depression. As a proportion of overall IHD burden, 2.95% (95% CI 1.48 to 4.46%) of IHD DALYs were estimated to be attributable to MDD in 2010. Eastern Europe and North Africa/Middle East demonstrate the highest proportion with Asia Pacific, high income representing the lowest.Conclusions
The present work comprises the most robust systematic review of its kind to date. The key finding that major depression may be responsible for approximately 3% of global IHD DALYs warrants assessment for depression in patients at high risk of developing IHD or at risk of a repeat IHD event.110.