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41.
Nir Uriel Diego Medvedofsky Teruhiko Imamura Jiri Maly Eric Kruse Peter Ivák Poornima Sood Roberto M. Lang Francesco Maffessanti Dominik Berliner Johann Bauersachs Axel Haverich Michael Želízko Ivan Netuka Jan D. Schmitto 《Journal of cardiac failure》2019,25(1):36-43
Background
The Heartmate 3 (HM3) is a Conformiteé Européenne mark–approved left ventricular (LV) assist device (LVAD) with fully magnetically levitated rotor and features consisting of a wide range operational speeds, wide flow paths, and artificial pulse. We performed a hemodynamic-echocardiographic speed optimization evaluation in HM3-implanted patients to achieve optimal LV- and right ventricular (RV) shape.Methods and Results
Sixteen HM3 patients underwent pump speed ramp tests with right heart catheterization. Three-dimensional echocardiographic (3DE) LV and RV datasets (Philips) were acquired, and volumetric (Tomtec) and shape (custom software) analyses were performed (LV: sphericity, conicity; RV: septal and free-wall curvatures). Data were recorded at up to 13 speed settings. Speed changes were in 100-rpm steps, starting at 4600 rpm and ramping up to 6200 rpm. 3DE was feasible in 50% of the patients. Mean original speed was 5306 ± 148 rpm. LV end-diastolic (ED) diameter (?0.15 ± 0.09 cm/100 rpm) and volumes (ED: 269 ± 109 mL to 175 ± 90 mL; end-systolic [ES]: 234 ± 111 mL to 146 ± 81 mL) progressively decreased as the shape became less spherical and more conical; RV volumes initially remained stable, but at higher speeds increased (ED: from 148 ± 64 mL to 181 ± 92 mL; ES: 113 ± 63 mL to 130 ± 69 mL). On average, the RV septum became less convex (bulging toward the LV) at the highest speeds.Conclusions
LV and RV shape changes were noted in HM3-supported patients. Although a LV volumetric decrease and shape improvement was consistently noted, RV volumes grew in response to increase in speed above a certain point. A next concern would be whether understanding of morphologic and function changes in LV and RV during LVAD speed change assessed with the use of 3DE helps to optimize LVAD speed settings and improve clinical outcomes. 相似文献42.
Vokurka J Olejnik J Jedlicka V Vesely M Ciernik J Paseka T 《Hepato-gastroenterology》2008,55(85):1349-1352
BACKGROUND/AIMS: Acute mesenteric ischemia (AMI) is a serious disease in old age with low incidence but with a very high mortality rate (60-70%). The etiology is either primary (embolism or thrombosis of mesenteric arteries or veins, non-occlusive mesenteric ischemia) or secondary (mechanical obstruction such as intestinal volvulus, intussusception, tumor-caused compression). Independent of the origin of the illness, the clinical-pathological picture is the same: intestinal ischemia with subsequent necrosis. The aim of this study was to ascertain which underlying conditions lead to increased probability of development of acute mesenteric ischemia. METHODS: Two hundred and fifteen patients with a primary form of AMI were treated in the years 1991-2007, in the 1st Clinic of Surgery in Brno, Czech Republic and in the Department of General Surgery, Derer's University Hospital in Bratislava, Slovak Republic; the results of the treatment have been statistically evaluated. CONCLUSION: The probability of arterial mesenteric ischemia development rises significantly (p < 0.05) in patients with a history of atrial fibrillation and/or myocardial infarction. This probability is also significantly higher in smokers with symptoms of hypertension and clinical signs of abdominal angina (p < 0.05). 相似文献
43.
Elio Schouppe Eva Van Overmeire Damya Laoui Jiri Keirsse Jo A. Van Ginderachter 《Immunobiology》2013,218(11):1385-1391
Myeloid-derived suppressor cells are immature myeloid cells, consisting of a monocytic and a granulocytic fraction, that are known to suppress anti-tumor immune responses. Important targets of the immunosuppressive capacity of MDSC are CD8+ T cells, which are crucial cytotoxic effector cells in immunotherapeutic settings. CD8+ T-cell activation and differentiation comprises a well-orchestrated series of events, starting from early TCR-mediated signaling and leading to cytokine secretion, the expression of activation markers, proliferation and the differentiation into several subsets of effector and memory cells. In this review, we summarize the available data on how the production of reactive oxygen species, nitric oxide, the arginase-mediated depletion of l-arginine and Cystine depletion by MDSCs interfere with the signaling molecules necessary for normal CTL differentiation and activation. 相似文献
44.
45.
Jitka Majovska Igor Nestrasil Amy Paulson David Nascene Katarina Jurickova Anna Hlavata Troy Lund Paul J. Orchard Manuela Vaneckova Jiri Zeman Martin Magner Petr Dusek 《Molecular genetics and metabolism》2021,132(3):189-197
ObjectiveDespite profound neurological symptomatology there are only few MRI studies focused on the brain abnormalities in alpha-mannosidosis (AM). Our aim was to characterize brain MRI findings in a large cohort of AM patients along with clinical manifestations.MethodsTwenty-two brain MRIs acquired in 13 untreated AM patients (8 M/5F; median age 17 years) were independently assessed by three experienced readers and compared to 16 controls.ResultsFocal and/or diffuse hyperintense signals in the cerebral white matter were present in most (85%) patients. Cerebellar atrophy was common (62%), present from the age of 5 years. Progression was observed in two out of 6 patients with follow-up scans. Cortical atrophy (62%) and corpus callosum thinning (23%) were already present in a 13-month-old child. The presence of low T2 signal intensity in basal ganglia and thalami was excluded by the normalized signal intensity profiling. The enlargement of perivascular spaces in white matter (38%), widening of perioptic CSF spaces (62%), and enlargement of cisterna magna (85%) were also observed. Diploic space thickening (100%), mucosal thickening (69%) and sinus hypoplasia (54%) were the most frequent non-CNS abnormalities.ConclusionWhite matter changes and cerebellar atrophy are proposed to be the characteristic brain MRI features of AM. The previously reported decreased T2 signal intensity in basal ganglia and thalami was not detected in this quantitative study. Rather, this relative MR appearance seems to be related to the diffuse high T2 signal in the adjacent white matter and not the gray matter iron deposition that has been hypothesized. 相似文献
46.
Coding variants of TLR2 and TLR4 genes do not substantially contribute to prosthetic joint infection
Objective and design
Prosthetic joint infection (PJI) is a severe complication of total joint arthroplasty (TJA). We conducted a genetic association study that investigated whether selected coding variants of the genes for Toll-like receptors (TLR)2 and TLR4 may contribute to genetic susceptibility for PJI.Subjects and methods
In total, 350 patients with TJA (98 with PJI/252 without PJI), and 189 unrelated healthy Czech individuals without TJA were enrolled in our study. Three missense polymorphisms of the genes encoding for TLR2 (TLR2 R753Q, rs5743708) and TLR4 (TLR4 D299G, rs4986790 and T399I, rs4986791) were genotyped by “TaqMan” assay.Results
The frequencies of less common variants for the investigated TLR2/TLR4 polymorphisms in healthy individuals were similar to those observed in other Caucasian populations. Importantly, the distribution of TLR2/TLR4 genotype alleles did not differ between the patients with PJI and the control groups of patients with nonseptic prostheses/healthy individuals.Conclusion
Our data suggest that structural genetic variants of the receptors TLR2 and TLR4 do not substantially affect the risk of prosthetic joint infection. 相似文献47.
48.
49.
50.
Gerrit A. van Essen Jiri Beran Jeanne‐Marie Devaster Christelle Durand Xavier Duval Meral Esen Ann R. Falsey Gregory Feldman Pierre Gervais Bruce L. Innis Martina Kovac Odile Launay Geert Leroux‐Roels Janet E. McElhaney Shelly McNeil Mohammed Oujaa Jan Hendrik Richardus Guillermo Ruiz‐Palacios Richard H. Osborne Lidia Oostvogels 《Influenza and other respiratory viruses》2014,8(4):452-462