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981.
982.
Alison S. Care Kerrilyn R. Diener Melinda J. Jasper Hannah M. Brown Wendy V. Ingman Sarah A. Robertson 《The Journal of clinical investigation》2013,123(8):3472-3487
Macrophages are prominent in the uterus and ovary at conception. Here we utilize the Cd11b-Dtr mouse model of acute macrophage depletion to define the essential role of macrophages in early pregnancy. Macrophage depletion after conception caused embryo implantation arrest associated with diminished plasma progesterone and poor uterine receptivity. Implantation failure was alleviated by administration of bone marrow–derived CD11b+F4/80+ monocytes/macrophages. In the ovaries of macrophage-depleted mice, corpora lutea were profoundly abnormal, with elevated Ptgs2, Hif1a, and other inflammation and apoptosis genes and with diminished expression of steroidogenesis genes Star, Cyp11a1, and Hsd3b1. Infertility was rescued by exogenous progesterone, which confirmed that uterine refractoriness was fully attributable to the underlying luteal defect. In normally developing corpora lutea, macrophages were intimately juxtaposed with endothelial cells and expressed the proangiogenic marker TIE2. After macrophage depletion, substantial disruption of the luteal microvascular network occurred and was associated with altered ovarian expression of genes that encode vascular endothelial growth factors. These data indicate a critical role for macrophages in supporting the extensive vascular network required for corpus luteum integrity and production of progesterone essential for establishing pregnancy. Our findings raise the prospect that disruption of macrophage-endothelial cell interactions underpinning corpus luteum development contributes to infertility in women in whom luteal insufficiency is implicated. 相似文献
983.
Goksel Guven Milos Brankovic Alina A. Constantinescu Jasper J. Brugts Dennis A. Hesselink Sakir Akin Ard Struijs Ozcan Birim Can Ince Olivier C. Manintveld Kadir Caliskan 《Intensive care medicine》2018,44(5):588-597
Purpose
Acute kidney injury (AKI) frequently occurs after heart transplantation (HTx), but its relation to preoperative right heart hemodynamic (RHH) parameters remains unknown. Therefore, we aimed to determine their predictive properties for postoperative AKI severity within 30 days after HTx.Methods
From 1984 to 2016, all consecutive HTx recipients (n?=?595) in our tertiary referral center were included and analyzed for the occurrence of postoperative AKI staged by the kidney disease improving global outcome criteria. The effects of preoperative RHH parameters on postoperative AKI were calculated using logistic regression, and predictive accuracy was assessed using integrated discrimination improvement (IDI), net reclassification improvement (NRI), and area under the receiver operating characteristic curves (AUC).Results
Postoperative AKI occurred in 430 (72%) patients including 278 (47%) stage 1, 66 (11%) stage 2, and 86 (14%) stage 3 cases. Renal replacement therapy (RRT) was administered in 41 (7%) patients. Patients with higher AKI stages had also higher baseline right atrial pressure (RAP; median 7, 7, 8, and in RRT 11 mmHg, p trend?=?0.021), RAP-to-pulmonary capillary wedge pressure ratio (median 0.37, 0.36, 0.40, 0.47, p trend?=?0.009), and lower pulmonary artery pulsatility index (PAPi) values (median 2.83, 3.17, 2.54, 2.31, p trend?=?0.012). Higher RAP and lower PAPi values independently predicted AKI severity [adjusted odds ratio (OR) per doubling of RAP 1.16 (1.02–1.32), p?=?0.029; of PAPi 0.85 (0.75–0.96), p?=?0.008]. Based on IDI, NRI, and delta AUC, inclusion of these parameters improved the models’ predictive accuracy.Conclusions
Preoperative PAPi and RAP strongly predict the development of AKI early after HTx and can be used as early AKI predictors.984.
Clinical and prognostic value of advanced glycation end-products in chronic heart failure. 总被引:2,自引:0,他引:2
Jasper W L Hartog Adriaan A Voors Casper G Schalkwijk Jean Scheijen Tom D J Smilde Kevin Damman Stephan J L Bakker Andries J Smit Dirk J van Veldhuisen 《European heart journal》2007,28(23):2879-2885
AIMS: Advanced glycation end-products (AGEs) have been proposed as a novel factor involved in the development and progression of chronic heart failure (CHF). We aimed to determine whether plasma levels of N(epsilon)-(carboxymethyl)lysine (CML) and N(epsilon)-(carboxyethyl)lysine (CEL), two well-known AGEs, are related to the severity and prognosis of CHF. METHODS AND RESULTS: A total of 102 CHF patients, aged 58 +/- 12 years, with an average left ventricular ejection fraction of 28 +/- 9% were followed for 1.7 (1.2-1.9) years. NYHA functional class and NT-pro-BNP were used as estimates of the severity of CHF. CML and CEL were determined by LC-MS/MS. CML levels were associated with NYHA functional class (P < 0.001) and NT-pro-BNP levels (P < 0.001). Survival analysis for the combined end-point of death, heart transplantation, ischaemic cardiovascular event, and hospitalization for heart failure revealed that CML levels predicted outcome, even after adjustment for age, gender, aetiology of CHF, identified risk modifiers, and several known predictors of outcome in CHF. The predictive value of CML subsided after correction for renal function. CEL was not associated with the severity or prognosis of CHF. CONCLUSION: Plasma AGEs, in particular CML levels, are related to the severity and prognosis of CHF. The fact that the relation between CML and prognosis subsided after correction for renal function may suggest that AGE accumulation in renal failure explains part of the prognostic value of renal function in CHF. However, further investigation is warranted to exclude the possibility that CML is just an innocent marker of renal function. 相似文献
985.
Activation delay and VT parameters in arrhythmogenic right ventricular dysplasia/cardiomyopathy: toward improvement of diagnostic ECG criteria 总被引:1,自引:0,他引:1
Cox MG Nelen MR Wilde AA Wiesfeld AC van der Smagt JJ Loh P Cramer MJ Doevendans PA van Tintelen JP de Bakker JM Hauer RN 《Journal of cardiovascular electrophysiology》2008,19(8):775-781
Introduction: Desmosomal changes, electrical uncoupling, and surviving myocardial bundles embedded in fibrofatty tissue are hallmarks of activation delay in arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C). Currently, generally accepted task force criteria (TFC) are used for clinical diagnosis. We propose additional criteria based on activation delay and ventricular tachycardia (VT) to improve identification of affected individuals.
Methods and Results: Activation delay and VT-related 12-lead electrocardiographic (ECG) criteria were studied, while off drugs, in 42 patients with proven ARVD/C according to TFC, and 27 controls with idiopathic VT from the RV outflow tract. Two of three measured TFC could only be identified in a small minority of ARVD/C patients. Additional ECG criteria proposed in this study included (a) prolonged terminal activation duration, an indicator of activation delay; (b) VT with LBBB morphology and superior axis; and (c) multiple different VT morphologies. These criteria were met in 30 (71%), 28 (67%), and 37 (88%) ARVD/C patients, respectively, and in one control patient (P < 0.001). Electrophysiologic studies contributed importantly to yield different VT morphologies. Pathogenic plakophilin-2 mutations were identified in 25 (60%) of ARVD/C patients and in none of the controls. In ARVD/C patients, parameters measured were not significantly different between mutation carriers and noncarriers, except for negative T waves in V1–3, occurring more frequently in patients with mutation.
Conclusions: The proposed additional criteria are specific for ARVD/C and more sensitive than the current TFC. Therefore, adding the newly proposed criteria to current TFC could improve ARVD/C diagnosis, independent of DNA analysis. 相似文献
Methods and Results: Activation delay and VT-related 12-lead electrocardiographic (ECG) criteria were studied, while off drugs, in 42 patients with proven ARVD/C according to TFC, and 27 controls with idiopathic VT from the RV outflow tract. Two of three measured TFC could only be identified in a small minority of ARVD/C patients. Additional ECG criteria proposed in this study included (a) prolonged terminal activation duration, an indicator of activation delay; (b) VT with LBBB morphology and superior axis; and (c) multiple different VT morphologies. These criteria were met in 30 (71%), 28 (67%), and 37 (88%) ARVD/C patients, respectively, and in one control patient (P < 0.001). Electrophysiologic studies contributed importantly to yield different VT morphologies. Pathogenic plakophilin-2 mutations were identified in 25 (60%) of ARVD/C patients and in none of the controls. In ARVD/C patients, parameters measured were not significantly different between mutation carriers and noncarriers, except for negative T waves in V1–3, occurring more frequently in patients with mutation.
Conclusions: The proposed additional criteria are specific for ARVD/C and more sensitive than the current TFC. Therefore, adding the newly proposed criteria to current TFC could improve ARVD/C diagnosis, independent of DNA analysis. 相似文献
986.
Roeland Eppenga Koert Kuhlmann Theo Ruers Jasper Nijkamp 《International journal of computer assisted radiology and surgery》2018,13(12):1937-1948
Purpose
To evaluate the applicability of the Calypso® wireless transponder tracking system (Varian Medical Systems Inc., USA) for real-time tumor motion tracking during surgical procedures on tumors in non-rigid target areas. An accuracy assessment was performed for an extended electromagnetic field of view (FoV) of 27.5?×?27.5?×?22.5 cm (which included the standard FoV of 14?×?14?×?19 cm) in which 5DOF wireless Beacon® transponders can be tracked.Methods
Using a custom-made measurement setup, we assessed single transponder relative accuracy, absolute accuracy and jitter throughout the extended FoV at 1440 locations interspaced with 2.5 cm in each orthogonal direction. The NDI Polaris Spectra optical tracking system (OTS) was used as a reference. Measurements were taken in a room without surrounding distorting factors and repeated in an operating room (OR). In the OR, the influence of a carbon fiber and regular stainless steel OR tabletop was investigated.Results
The calibration of the OTS and transponder system resulted in an average root-mean-square error (RMSE) vector of 0.03 cm. For both the standard and extended FoV, all accuracy measures were dependent on transponder to tracking array (TA) distances and the absolute accuracy was also dependent on TA to OR tabletop distances. This latter influence was reproducible, and after calibrating this, the residual error was below 0.1 cm RMSE within the entire standard FoV. Within the extended FoV, this residual RMSE did not exceed 0.1 cm for transponder to TA distances up to 25 cm.Conclusion
This study shows that transponder tracking is promising for accurate tumor tracking in the operating room. This applies when using the standard FoV, but also when using the extended FoV up to 25 cm above the TA, substantially increasing flexibility.987.
988.
Theo van den Broek Eveline M. Delemarre Willemijn J.M. Janssen Rutger A.J. Nievelstein Jasper C. Broen Kiki Tesselaar Jose A.M. Borghans Edward E.S. Nieuwenhuis Berent J. Prakken Michal Mokry Nicolaas J.G. Jansen Femke van Wijk 《The Journal of clinical investigation》2016,126(3):1126-1136
The generation of naive T cells is dependent on thymic output, but in adults, the naive T cell pool is primarily maintained by peripheral proliferation. Naive T cells have long been regarded as relatively quiescent cells; however, it was recently shown that IL-8 production is a signatory effector function of naive T cells, at least in newborns. How this functional signature relates to naive T cell dynamics and aging is unknown. Using a cohort of children and adolescents who underwent neonatal thymectomy, we demonstrate that the naive CD4+ T cell compartment in healthy humans is functionally heterogeneous and that this functional diversity is lost after neonatal thymectomy. Thymic tissue regeneration later in life resulted in functional restoration of the naive T cell compartment, implicating the thymus as having functional regenerative capacity. Together, these data shed further light on functional differentiation within the naive T cell compartment and the importance of the thymus in human naive T cell homeostasis and premature aging. In addition, these results affect and alter our current understanding on the identification of truly naive T cells and recent thymic emigrants. 相似文献
989.
990.
Richard G. Heimberg Ph.D. Stefan G. Hofmann Ph.D. Michael R. Liebowitz M.D. Franklin R. Schneier M.D. Jasper A. J. Smits Ph.D. Murray B. Stein M.D. M.P.H. Devon E. Hinton M.D. Ph.D. Michelle G. Craske Ph.D. 《Depression and anxiety》2014,31(6):472-479
With the publication of DSM‐5, the diagnostic criteria for social anxiety disorder (SAD, also known as social phobia) have undergone several changes, which have important conceptual and clinical implications. In this paper, we first provide a brief history of the diagnosis. We then review a number of these changes, including (1) the primary name of the disorder, (2) the increased emphasis on fear of negative evaluation, (3) the importance of sociocultural context in determining whether an anxious response to a social situation is out of proportion to the actual threat, (4) the diagnosis of SAD in the context of a medical condition, and (5) the way in which we think about variations in the presentation of SAD (the specifier issue). We then consider the clinical implications of changes in DSM‐5 related to these issues. 相似文献