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91.
Christian?Tesche Carlo?N.?De Cecco Andrew?Stubenrauch Brian?E.?Jacobs Akos?Varga-Szemes Sheldon?E.?Litwin B. Devon?Ball Moritz?Baquet David?Jochheim Ullrich?Ebersberger Richard?R.?Bayernd Ellen?Hoffmann Daniel?H.?Steinberg U. Joseph?Schoepf 《La Radiologia medica》2017,122(2):113-120
Objective
To evaluate the correlation between aortic root calcification (ARC) markers and coronary artery calcification (CAC) derived from coronary artery calcium scoring (CACS) and their ability to predict obstructive coronary artery disease (CAD).Methods
We retrospectively analyzed 189 patients (47% male, age 60.3 ± 11.1 years) with an intermediate probability of CAD who underwent clinically indicated CACS and coronary CT angiography (CCTA). ARC markers [aortic root calcium score (ARCS) and volume (ARCV)] were calculated and compared to CAC markers: coronary artery calcium score (CACS), volume (CACV), and mass (CACM). CCTA datasets were visually evaluated for significant CAD (stenosis ≥ 50%) and the ability of ARC markers to predict obstructive CAD was assessed.Results
ARCS (mean 67.7 ± 189.5) and ARCV (mean 67.3 ± 184.7) showed significant differences between patients with and without CAC (109.4 ± 238.6 vs 9.42 ± 31.4, p < 0.0001; 108.5 ± 232.4 vs 9.9 ± 30.5, p < 0.0001). A strong correlation was found for ARCS and ARCV with CACS, CACM, and CACV (all p < 0.0001). In a multivariate analysis, ARCS (OR 1.09, p = 0.033) and ARCV (OR 1.12, p = 0.046) were independent markers for CAC. Using a receiver-operating characteristics analysis, the AUC to detect severe CAC was 0.71 (p < 0.0001) and 0.71 (p < 0.0001) for ARCS and ARCV, respectively. ARCS (0.67, p < 0.0001) and ARCV (0.68, p < 0.0001) showed discriminatory power for predicting obstructive CAD, yielding sensitivities 61 and 78% and specificities of 62 and 80%, respectively.Conclusion
ARC markers are associated with and independently predict the presence of CAC and obstructive CAD. Further testing is required in patients with severe ARC and significant CAD in order to reliably obtain these markers from thoracic-CT or X-ray for proper risk classification.92.
Bagi Z Feher A Cassuto J Akula K Labinskyy N Kaley G Koller A 《British journal of pharmacology》2011,163(5):1059-1068
BACKGROUND AND PURPOSE
Antagonists of angiotensin AT1 receptors elicit beneficial vascular effects in diabetes mellitus. We hypothesized that diabetes induces sustained availability of AT1 receptors, causing enhanced arterial constriction to angiotensin II.EXPERIMENTAL APPROACH
To assess functional availability of AT1 receptors, constrictions to successive applications of angiotensin II were measured in isolated skeletal muscle resistance arteries (∼150 µm) of Zucker diabetic fatty (ZDF) rats and of their controls (+/Fa), exposed acutely to high glucose concentrations (HG, 25 mM, 1 h). AT1 receptors on cell membrane surface were measured by immunofluorescence.KEY RESULTS
Angiotensin II-induced constrictions to first applications were greater in arteries of ZDF rats (maximum: 82 ± 3% original diameter) than in those from +/Fa rats (61 ± 5%). Constrictions to repeated angiotensin II administration were decreased in +/Fa arteries (20 ± 6%), but were maintained in ZDF arteries (67 ± 4%) and in +/Fa arteries vessels exposed to HG (65 ± 6%). In ZDF arteries and in HG-exposed +/Fa arteries, Rho-kinase activities were enhanced. The Rho-kinase inhibitor, Y27632 inhibited sustained constrictions to angiotensin II in ZDF arteries and in +/Fa arteries exposed to HG. Levels of surface AT1 receptors on cultured vascular smooth muscle cells (VSMCs) were decreased by angiotensin II but were maintained in VSMCs exposed to HG. In VSMCs exposed to HG and treated with Y27632, angiotensin II decreased surface AT1 receptors.CONCLUSIONS AND IMPLICATIONS
In diabetes, elevated glucose concentrations activate Rho-kinase which inhibits internalization or facilitates recycling of AT1 receptors, leading to increased functional availability of AT1 receptors and sustained angiotensin II-induced arterial constriction. 相似文献93.
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96.
Joó JG Beke A Szigeti Z Csaba A Mezei G Tóth-Pál E Papp C 《Early human development》2008,84(2):115-119
BACKGROUND: Craniospinal malformations represent a heterogeneous group of congenital malformations by their morphology and etiology alike. Certain craniospinal malformations could be diagnosed as early as the dawn of ultrasonography and this group of malformations has been the focus of attention ever since. AIMS:: The aim of the authors was to review the main characteristics of craniospinal malformations, as well as to evaluate the efficiency of ultrasonography based on autopsy examinations during twelve years. STUDY DESIGN: The current study comprises the details of 339 pregnancies terminated by induced abortion for craniospinal malformation between 1995 and 2006. RESULTS: Maternal median age was 27+/-5.8 years, ranging from 15 to 47 years. In 24.5% of the cases, there was a positive obsterical-gynecological or genetic history. In 68.1% of the cases, ultrasonographic and autopsy findings were completely identical; in 24.2% a partial coincidence was found, but autopsy allowed for further diagnoses, while in 26 cases (7.7%) different findings were obtained by prenatal ultrasonography and fetopathological investigations. In half of the latter 26 cases, induced abortion was suggested due to hydrocephalus confirmed by ultrasonography but not justified by autopsy or the autopsy revealed the presence of other craniospinal malformation(s). CONCLUSION: It can be concluded that - in view of the diagnostic efficiency of fetopathological investigations - the ultrasonographic diagnosis of hydrocephalus should be interpreted independently from other craniospinal malformations on the basis of principles of ultrasonographic methodology and at different times. 相似文献
97.
PURPOSE: Terrien disease is a rare form of peripheral corneal degeneration characterized by vascularization, opacification, lipid deposition, and corneal thinning. In this study, a high-frequency ultrasound biomicroscope (UBM) was used to detect the morphologic changes before and after surgery and to determine the stages of this disease. METHODS: Two patients with Terrien disease were examined by UBM, corneal topography, and a keratometer before and after surgery (full-thickness keratectomy). RESULTS: The absence of the Bowman layer and thinning of the Descemet layer in the ectatic part of the peripheral cornea were detected by using the UBM before surgery. Earlier, these signs could be detected only with optical and electron microscopy from histologic samples; now we can detect the signs of Terrien disease with noninvasive devices such as the UBM. CONCLUSIONS: The UBM is an effective device for following the progression of Terrien disease and determining the timing of these patients' surgeries. 相似文献
98.
Gert Jan Pelgrim Taylor M. Duguay J. Marco A. Stijnen Akos Varga-Szemes Sjoerd Van Tuijl U. Joseph Schoepf Matthijs Oudkerk Rozemarijn Vliegenthart 《Journal of Cardiovascular Computed Tomography》2017,11(2):141-147
Purpose
To evaluate the relationship between fractional flow reserve (FFR)-determined coronary artery stenosis severity and myocardial perfusion parameters derived from dynamic myocardial CT perfusion imaging (CTP) in an ex-vivo porcine heart model.Methods
Six porcine hearts were perfused according to Langendorff. Circulatory parameters such as arterial blood flow (ABF) (L/min), mean arterial pressure (MAP) (mmHg) and heart rate (bpm) were monitored. Using an inflatable cuff and monitored via a pressure wire, coronary artery stenoses of different FFR grades were created (no stenosis, FFR = 0.80, FFR = 0.70, FFR = 0.60, and FFR = 0.50). Third generation dual-source CT was used to perform dynamic CTP in shuttle mode at 70 kV. Using the AHA-16-segment model, myocardial blood flow (MBF) (mL/100 mL/min) and volume (MBV) (mL/100 mL) were analyzed using dedicated software for all ischaemic and non-ischaemic segments.Results
During five successful experiments, ABF ranged from 0.8 to 1.2 L/min, MAP from 73 to 90 mmHg and heart rate from 83 to 115 bpm. Non-ischaemic and ischaemic segments showed significant differences in MBF for stenosis grades of FFR ≤ 0.70. At this degree of obstruction, median MBF was 79 (interquartile range [IQR]: 66–90) for non-ischaemic segments versus 56 mL/100 mL/min (IQR: 46–73) for ischaemic segments (p < 0.05). For MBV, a significant difference was found at FFR ≤ 0.80 with median MBV values of 7.6 (IQR: 7.0–8.3) and 7.1 mL/100 mL (IQR: 6.0–8.2) for non-ischaemic and ischaemic myocardial segments, respectively (p < 0.05).Conclusion
Artificial flow alterations in a Langendorff porcine heart model could be detected and measured by CTP-derived myocardial perfusion parameters and showed significant systematic correlation with stepwise flow reduction that permitted early detection of ischaemic myocardium. Additional research in clinical setting is required to develop absolute quantitative CTP. 相似文献99.
Paul A. Fenton Coen Hurkmans Akos Gulyban Jorien van der Leer Oscar Matzinger Philip Poortmans Laurence Collette Michel Bolla 《Radiotherapy and oncology》2013
Background and purpose
The EORTC 22043-30041 trial investigates the role of the addition of androgen suppression to post-operative radiotherapy in patients who have undergone radical prostatectomy. As part of the quality assurance of radiotherapy (QART) a Dummy Run (DR) procedure was performed.Materials and method
The protocol included detailed and published delineation guidelines. Participating institutions digitally submitted radiotherapy treatment volumes and a treatment plan for a standard clinical case. Submissions were centrally reviewed using the VODCA software platform.Results
Thirty-eight submissions from thirty-one institutions were reviewed. Six were accepted without comments. Twenty-three were accepted with comments on one or more items: target volume delineation (22), OAR delineation (23), planning and dosimetry (3) or treatment verification (1). Nine submissions were rejected requiring resubmission, seven for target volume delineation reasons alone. Intervention to highlight the importance of delineation guidelines was made prior to the entry of the first patient in the trial. After this, a lower percentage of resubmissions was required.Conclusions
The EORTC 22043-30041 Dummy Run highlights the need for timely and effective QART in clinical trials. The variation in target volume and OAR definition demonstrates that clinical guidelines and radiotherapy protocols are not a substitute for QART procedures. Early intervention in response to the Dummy Run improved protocol understanding. 相似文献100.
Kovacs A Hadjiev J Lakosi F Glavak C Antal G Bogner P Horvath A Repa I 《Pathology oncology research : POR》2008,14(2):193-197
In the treatment of early stage breast cancer breast conserving surgery (BCS) followed by whole breast irradiation (WBI) is a standard method. The impact of the tumor bed boost following WBI is well-defined, but there are various delivery methods. In this study the electron and the photon boost techniques were compared. For 78 early stage breast cancer patients both CT based 3D conformal photon boost and electron boost plans were created. For dosimetric comparison coverage index (CI), external volume index (EI) and conformality index (COIN) were studied. Lung volume receiving a dose of 2 Gy was also reviewed. Seventy-eight patients with 156 plans were compared. The mean tumor bed volume was measured as 61.39 cm(3) the mean tumor bed-skin distance was 3.13 cm. In the case of CI and COIN significant differences were found in favor of the photon boost. In the comparison of EI no significant difference was detected between the two techniques. The mean lung volume receiving 2 Gy were 42.3 and 168.35 cm(3), for photons and electrons respectively. In the adjuvant treatment of early stage breast cancer WBI followed by conformal photon boost showed to be superior to electron boost in focus of the COIN and CI. 相似文献