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111.
112.
Thomas Fink MD Vanessa Sciacca MD Christian-Hendrik Heeger MD Julia Vogler MD Charlotte Eitel MD Bruno Reissmann MD Laura Rottner MD Andreas Rillig MD Shibu Mathew MD Tilman Maurer MD Feifan Ouyang MD Karl-Heinz Kuck MD Andreas Metzner MD Roland Richard Tilz MD 《Pacing and clinical electrophysiology : PACE》2020,43(10):1115-1125
113.
Atrial fibrillation in heart failure often occur together. The relationship between atrial fibrillation and heart failure has remained a subject of research. The main manifestation of the violation of hydrodynamics in heart failure is the increased end-diastolic pressure, which is transmitted through the intercommunicated system (left ventricle–left atrium–pulmonary veins–alveolar capillaries) causing increased pulmonary wedge pressure with the danger for pulmonary edema. End-diastolic pressure is the sum of left ventricle diastolic pressure and left atrial systolic pressure. Stopping the mechanical systole of the left atrium can reduce the pressure in the system in heart failure. Atrial fibrillation stops the mechanical systole of the left atrium and decreases the intercommunicating pressure and pulmonary wedge pressure. It is possible that atrial fibrillation is a mechanism for protection from increasing end-diastolic pressure and pulmonary wedge pressure, and prevents the danger of pulmonary edema. This hypothesis may explain the relationship between heart failure and atrial fibrillation and their frequent association. 相似文献
114.
Ayala Tovy Carina Rosas Amos S. Gaikwad Geraldo Medrano Linda Zhang Jaime M. Reyes Yung-Hsin Huang Tatsuhiko Arakawa Kristen Kurtz Shannon E. Conneely Anna G. Guzman Rogelio Aguilar Anne Gao Chun-Wei Chen Jean J. Kim Melissa T. Carter Amaia Lasa-Aranzasti Irene Valenzuela Lionel Van Maldergem Lorenzo Brunetti M. John Hicks Andrea N. Marcogliese Margaret A. Goodell Rachel E. Rau 《Haematologica》2022,107(4):887
Tatton-Brown-Rahman syndrome (TBRS) is an overgrowth disorder caused by germline heterozygous mutations in the DNA methyltransferase DNMT3A. DNMT3A is a critical regulator of hematopoietic stem cell (HSC) differentiation and somatic DNMT3A mutations are frequent in hematologic malignancies and clonal hematopoiesis. Yet, the impact of constitutive DNMT3A mutation on hematopoiesis in TBRS is undefined. In order to establish how constitutive mutation of DNMT3A impacts blood development in TBRS we gathered clinical data and analyzed blood parameters in 18 individuals with TBRS. We also determined the distribution of major peripheral blood cell lineages by flow cytometric analyses. Our analyses revealed non-anemic macrocytosis, a relative decrease in lymphocytes and increase in neutrophils in TBRS individuals compared to unaffected controls. We were able to recapitulate these hematologic phenotypes in multiple murine models of TBRS and identified rare hematological and non-hematological malignancies associated with constitutive Dnmt3a mutation. We further show that loss of DNMT3A in TBRS is associated with an altered DNA methylation landscape in hematopoietic cells affecting regions critical to stem cell function and tumorigenesis. Overall, our data identify key hematopoietic effects driven by DNMT3A mutation with clinical implications for individuals with TBRS and DNMT3A-associated clonal hematopoiesis or malignancies. 相似文献
115.
Inducible nitric oxide synthase (iNOS) and endothelial nitric oxide synthase (eNOS) expression in fulminant hepatic failure 总被引:1,自引:0,他引:1
Leifeld L Fielenbach M Dumoulin FL Speidel N Sauerbruch T Spengler U 《Journal of hepatology》2002,37(5):613-619
BACKGROUND/AIMS: Inducible nitric oxide synthase (iNOS) and endothelial nitric oxide synthase (eNOS) have important functions in inflammation and vasoregulation but their role in fulminant hepatic failure (FHF) is not well understood. METHODS: Intrahepatic in situ staining and semi-quantification of iNOS and eNOS by immunohistochemistry in 25 patients with FHF, in 40 patients with chronic liver diseases (CLD) and in ten normal controls (NC). RESULTS: Expression patterns of iNOS and eNOS differed. While in NC only faint iNOS expression was found in some Kupffer cells/macrophages and hepatocytes, eNOS was expressed constitutively in sinusoidal and vascular endothelial cells. In CLD, iNOS expression was induced in Kupffer cells/macrophages and hepatocytes, representing the main iNOS expressing cell types. Additionally, bile ducts, vascular endothelial cells and lymphocytes also expressed iNOS (P = 0.001). In contrast, no differences were found between eNOS expression in CLD and NC (P = 0.64). The same cell types expressed eNOS and iNOS in FHF but numbers of both were significantly enhanced, exceeding the levels seen in CLD (P < 0.001, P = 0.017). CONCLUSIONS: Our data demonstrate that iNOS and eNOS are differently regulated in physiologic conditions and in liver disease. While eNOS seems to be involved in the physiological regulation of hepatic perfusion, strong upregulation of iNOS might contribute to inflammatory processes in FHF. 相似文献
116.
Andra-Iza Iuga Lenhard Pennig Liliana Lourenco Caldeira David Maintz Tilman Hickethier Jonas Doerner 《Medicine》2021,100(48)
To determine if anemia can be predicted on enhanced computed tomography (CT) examinations of the thorax using virtual non-contrast (VNC) images, in order to support clinicians especially in diagnosing primary asymptomatic patients in daily routine.In this monocentric study, 100 consecutive patients (50 with proven anemia), who underwent a contrast-enhanced CT examination of the thorax due to various indications were included. Attenuation was measured in the descending thoracic aorta, the intraventricular septum, and the left ventricle cavity both in the conventional contrast-enhanced and in the VNC images.Two experienced radiologists annotated the delineation of a dense interventricular septum or a hyperattenuating aortic wall sign for all patients.Hemoglobin levels were then correlated with the measured attenuation values, as well as the visualization of the aortic wall or interventricular septum.Good correlation was shown between hemoglobin levels and CT attenuation values of the left ventricular cavity (r = .59), aorta (r = .56), and ratio between left ventricular cavity and the intraventricular septum (r = .57). Receiver operating characteristic curve revealed ≤ 36.5 hounsfield units (left ventricular cavity) as the threshold for diagnosing anemia. Predicting anemia by visualization of a hyperattenuating aortic wall or a dense interventricular septum yielded a specificity of 98% and 92%, respectively.Predicting anemia on enhanced CT examinations using VNC is feasible. A threshold value of ≤ 36.5 hounsfield units (left ventricular cavity) best defines anemia. Aortic wall or interventricular septum visualization on VNC is a specific anemia indicator. 相似文献
117.
118.
Saman K. Hashmi Shoba A. Navai Tiffany M. Chambers Michael E. Scheurer M. John Hicks Rachel E. Rau Maria M. Gramatges 《Pediatric blood & cancer》2020,67(2)
Conjugated hyperbilirubinemia (CHB) and liver transaminase elevation are known complications of acute lymphoblastic leukemia (ALL) therapy, but host risk factors are poorly understood. Among 373 children diagnosed with ALL between 2011 and 2016, clinically significant CHB and transaminase elevation were observed in 15 (4.0%) and 12 (3.2%) children, respectively, during induction and consolidation. Body mass index ≥95th percentile (odds ratio 9.20, 95% confidence interval 2.56–32.96) was the only host factor independently associated with CHB, and no host factors were associated with transaminase elevation. Obese patients warrant closer monitoring of hepatic function to facilitate early intervention prior to the development of severe, adverse hepatic events. 相似文献
119.
Michael T. Barbe MD Lisa Tonder MS Paul Krack MD PhD Bettina Debû MD Michael Schüpbach MD Steffen Paschen MD Till A. Dembek MD Andrea A. Kühn MD Valerie Fraix MD Christine Brefel-Courbon MD PhD Lars Wojtecki MD PhD David Maltête MD PhD Phillippe Damier MD PhD Friederike Sixel-Döring MD Daniel Weiss MD Marcus Pinsker MD PhD Tatiana Witjas MD PhD Stephane Thobois MD PhD Carmen Schade-Brittinger B.Sc Jörn Rau MSc Jean-Luc Houeto MD PhD Andreas Hartmann MD PhD Lars Timmermann MD PhD Alfons Schnitzler MD PhD Valerie Stoker MPH Marie Vidailhet MD PhD Günther Deuschl MD PhD for the EARLYSTIM study group 《Movement disorders》2020,35(1):82-90