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91.
Ravil Sharifulin Alexander Bogachev-Prokophiev Sergey Zheleznev Igor Demin Alexey Pivkin Alexander Afanasyev Alexander Karaskov 《The Journal of thoracic and cardiovascular surgery》2019,157(1):134-141.e3
Objective
Although the Ross procedure provides excellent long-term survival and a high quality of life, its use has been limited to relatively few centers. In this study, we evaluated long-term Ross procedure results in adults to assess the predictors of pulmonary autograft durability.Methods
Between 1998 and 2015, 793 consecutive adult patients underwent the Ross procedure. The total root replacement technique was used in all patients.Results
The early mortality rate was 2.9%. The mean follow-up duration was 6.5 ± 3.2 years, and the 10-year survival rate was 90.4%. Longitudinal mixed-effects ordinal regression identified a combination of bicuspid aortic valve and aortic insufficiency (odds ratio, 2.19; P < .001) as predictors for progression of autograft valve insufficiency at follow-up. The cumulative incidence of autograft reoperations at 10 years was 8.6%. Competing risk regression identified bicuspid aortic valve insufficiency as the independent predictor of autograft reoperation (subdistribution hazard ratio, 2.16; P = .030). Moreover, patients with bicuspid aortic valve and aortic insufficiency had greater increases in annulus (P < .001), sinus (P < .001), and ascending aorta (P < .001) diameters over time.Conclusions
For patients undergoing the Ross procedure, a combination of bicuspid aortic valves and aortic insufficiency is the main risk factor for late autograft dilatation and dysfunction. 相似文献92.
Anirban P. Mitra Adrian S. Fairey Eila C. Skinner Stephen A. Boorjian Igor Frank Mark P. Schoenberg Trinity J. Bivalacqua M. Eric Hyndman Adam C. Reese Gary D. Steinberg Michael C. Large Christina A. Hulsbergen-van de Kaa Harman M. Bruins Siamak Daneshmand 《Urologic oncology》2019,37(1):48-56
Purpose
To determine the association of micropapillary urothelial carcinoma (MUC) variant histology with bladder cancer outcomes after radical cystectomy.Materials and Methods
Information on MUC patients treated with radical cystectomy was obtained from five academic centers. Data on 1,497 patients were assembled in a relational database. Tumor histology was categorized as urothelial carcinoma without any histological variants (UC; n?=?1,346) or MUC (n?=?151). Univariable and multivariable models were used to analyze associations with recurrence-free (RFS) and overall (OS) survival.Results
Median follow-up was 10.0 and 7.8 years for the UC and MUC groups, respectively. No significant differences were noted between UC and MUC groups with regard to age, gender, clinical disease stage, and administration of neoadjuvant and adjuvant chemotherapy (all, P ≥ 0.10). When compared with UC, presence of MUC was associated with higher pathologic stage (organ-confined, 60% vs. 27%; extravesical, 18% vs. 23%; node-positive, 22% vs. 50%; P < 0.01) and lymphovascular invasion (29% vs. 58%; P < 0.01) at cystectomy. In comparison with UC, MUC patients had poorer 5-year RFS (70% vs. 44%; P < 0.01) and OS (61% vs. 38%; P < 0.01). However, on multivariable analysis, tumor histology was not independently associated with the risks of recurrence (P?=?0.27) or mortality (P?=?0.12).Conclusions
This multi-institutional analysis demonstrated that the presence of MUC was associated with locally advanced disease at radical cystectomy. However, clinical outcomes were comparable to those with pure UC after controlling for standard clinicopathologic predictors. 相似文献93.
94.
95.
Isabelle R. Miousse Marie‐Cécile G. Chalbot Nükhet Aykin‐Burns Xiaoying Wang Alexei Basnakian Ilias G. Kavouras Igor Koturbash 《Environmental and molecular mutagenesis》2014,55(5):428-435
Respiratory mortality and morbidity has been associated with exposure to particulate matter (PM). Experimental evidence suggests involvement of cytotoxicity, oxidative stress, and inflammation in the development of PM‐associated pathological states; however, the exact mechanisms remain unclear. In the current study, we analyzed short‐term epigenetic response to PM10 (particles with aerodynamic diameter less than 10 μm) exposure in mouse ascitic RAW264.7 macrophages (BALB/C Abelson murine leukemia virus‐induced tumor). Ambient PM10 was collected using a high volume sampler in Little Rock, AR. Analysis revealed that PM10 was composed mainly of Al and Fe, and the water soluble organic fraction was dominated by aliphatic and carbohydrate fragments and minor quantities of aromatic components. Exposure to PM10 compromised the cellular epigenome at concentrations 10–200 µg/ml. Specifically, epigenetic alterations were evident as changes in the methylation and expression of repetitive element‐associated DNA and associated DNA methylation machinery. These results suggest that epigenetic alterations, in concert with cytotoxicity, oxidative stress, and inflammation, might contribute to the pathogenesis of PM‐associated respiratory diseases. Environ. Mol. Mutagen. 55:428–435, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
96.
Julia Steinbach Henry Holmstrand Kseniia Shcherbakova Denis Kosmach Volker Brüchert Natalia Shakhova Anatoly Salyuk Clia J. Sapart Denis Chernykh Riko Noormets Igor Semiletov
rjan Gustafsson 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(10)
The East Siberian Arctic Shelf holds large amounts of inundated carbon and methane (CH4). Holocene warming by overlying seawater, recently fortified by anthropogenic warming, has caused thawing of the underlying subsea permafrost. Despite extensive observations of elevated seawater CH4 in the past decades, relative contributions from different subsea compartments such as early diagenesis, subsea permafrost, methane hydrates, and underlying thermogenic/ free gas to these methane releases remain elusive. Dissolved methane concentrations observed in the Laptev Sea ranged from 3 to 1,500 nM (median 151 nM; oversaturation by ∼3,800%). Methane stable isotopic composition showed strong vertical and horizontal gradients with source signatures for two seepage areas of δ13C-CH4 = (−42.6 ± 0.5)/(−55.0 ± 0.5) ‰ and δD-CH4 = (−136.8 ± 8.0)/(−158.1 ± 5.5) ‰, suggesting a thermogenic/natural gas source. Increasingly enriched δ13C-CH4 and δD-CH4 at distance from the seeps indicated methane oxidation. The Δ14C-CH4 signal was strongly depleted (i.e., old) near the seeps (−993 ± 19/−1050 ± 89‰). Hence, all three isotope systems are consistent with methane release from an old, deep, and likely thermogenic pool to the outer Laptev Sea. This knowledge of what subsea sources are contributing to the observed methane release is a prerequisite to predictions on how these emissions will increase over coming decades and centuries.The East Siberian Arctic Shelf (ESAS) is the world’s largest and shallowest shelf sea system, formed through inundation of northeast Siberia during sea level transgression in the early Holocene. The ESAS holds substantial but poorly constrained amounts of organic carbon and methane (CH4). These carbon/methane stores are contained in unknown partitions as gas hydrates, unfrozen sediment, subsea permafrost, gas pockets within and below the subsea permafrost, and as underlying thermogenic gas (1–3). Methane release to the atmosphere from these compartments could potentially have significant effects on the global climate (4, 5), yet there are large uncertainties regarding the size and the vulnerability toward remobilization of these inaccessible and elusive subsea carbon/methane pools. Conceptual development and modeling have predicted that warming of the ESAS system by a combination of geothermal heat and climate-driven Holocene heat flux from overlying seawater, recently further enhanced by Anthropocene warming, may lead to thawing of subsea permafrost (6, 7). Subsea permafrost drilling in the Laptev Sea, in part at the same sites as 30 y ago, has recently confirmed that the subsea permafrost has indeed come near the point of thawing (8). In addition to mobilization of the carbon/methane stored within the subsea permafrost, its degradation can also lead to the formation of pathways for gaseous methane from underlying reservoirs, allowing further methane release to the overlying water column (3, 9).Near-annual ship-based expeditions to the ESAS over the past two decades have documented widespread seep locations with extensive methane releases to the water column (3, 10). Methane levels are often found to be 10 to 100 times higher than the atmospheric equilibrium and are particularly elevated in areas of strong ebullition from subsea gas seeps (“methane hotspots”). Similarly, elevated dissolved methane concentrations in bottom waters appear to be spatially related to the thermal state of subsea permafrost as deduced from modeling results and/or geophysical surveys (7, 9). Currently, we lack critical knowledge on the quantitative or even relative contributions of the different subsea pools to the observed methane release, a prerequisite for robust predictions on how these releases will develop. An important distinction needs to be made between pools that release methane gradually, such as methane produced microbially in shallow sediments during early diagenesis or in thawing subsea permafrost, versus pools with preformed methane that may release more abruptly once pathways are available, such as from disintegrating methane hydrates and pools of thermogenic (natural) gas below the subsea permafrost. Multidimensional isotope analysis offers a useful means to disentangle the relative importance of these different subsea sources of methane to the ESAS: Stable isotope data (δ13C-CH4 and δD-CH4) provide useful information on methane formation and removal pathways, and the radiocarbon content of methane (Δ14C-CH4) helps to determine the age and methane source reservoir (see SI Appendix, text S1 for details on these isotope systematics and typical isotopic signatures for the ESAS subsea system).Here, we present triple-isotope–based source apportionment of methane conducted as part of the Swedish–Russian–US investigation of carbon–climate–cryosphere interactions in the East Siberian Arctic Ocean (SWERUS-C3) program. To this end, the distribution of dissolved methane, its stable carbon and hydrogen isotope composition, as well as natural radiocarbon abundance signature, were investigated with a focus on the isotopic fingerprint of methane escaping the seabed to pinpoint the subsea sources of elevated methane in the outer Laptev Sea. 相似文献
97.
Ulrika Evermann Christian Gaser Bianca Besteher Kerstin Langbein Igor Nenadi 《Schizophrenia bulletin》2020,46(6):1524
BackgroundPsychotic-like experiences (PLE) are present in nonclinical populations, yet their association with brain structural variation, especially markers of early neurodevelopment, is poorly understood. We tested the hypothesis that cortical surface gyrification, a putative marker of early brain development, is associated with PLE in healthy subjects. MethodsWe analyzed gyrification from 3 Tesla MRI scans (using CAT12 software) and PLE (positive, negative, and depressive symptom dimensions derived from the Community Assessment of Psychic Experiences, CAPE) in 103 healthy participants (49 females, mean age 29.13 ± 9.37 years). A subsample of 63 individuals completed tasks from the Wechsler Adult Intelligence Scale and Controlled Oral Word Association Test. Estimated IQ and a composite neuropsychological score were used to explore mediation pathways via cognition. ResultsPositive PLE distress was negatively associated with gyrification of the left precuneus. PLE depression dimension showed a negative association with gyrification in the right supramarginal and temporal region. There was no significant mediating effect of cognition on these associations. ConclusionOur results support a neurobiological psychosis spectrum, for the first time linking an early developmental imaging marker (rather than volume) to dimensional subclinical psychotic symptoms. While schizophrenia risk, neurodevelopment, and cognitive function might share genetic risk factors, additional mediation analyses did not confirm a mediating effect of cognition on the gyrification-psychopathology correlation. 相似文献
98.
99.
Rashida Hussain Igor Oliynyk Godfried M. Roomans Maria Björkqvist 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2013,121(9):814-826
Bacteria affect the respiratory epithelium, which is covered by airway surface liquid (ASL) and mucus. Ion concentrations in the ASL are determined by the cystic fibrosis transmembrane conductance regulator (CFTR) and the epithelial Na+ channel (ENaC). Neonatal sepsis is a major risk factor for subsequent pulmonary disease in preterm newborns. Predominating are coagulase‐negative staphylococci (e.g., Staphylococccus epidermidis and Staphylococccus aureus). The aim of this study was to investigate modulation of CFTR, ENaC, mucins, proinflammatory cytokines, and inducible nitric oxide synthase (iNOS) in respiratory epithelial cells after S. epidermidis 94B080 and S. aureus 90B083 exposure. Bronchial epithelial cells were incubated with S. epidermidis 94B080 and S. aureus 90B083 (neonatal blood isolates) for 1–36 h. Expression of CFTR, ENaC, iNOS, and mucins was analyzed by real‐time PCR and Western blotting. Release of cytokines was analyzed by ELISA, and production of NO by the Griess assay. Expression of CFTR significantly decreased after 36 h incubation with S. epidermidis and more prominently with S. aureus, whereas S. epidermidis caused a significant increase in the expression of β‐ and γ‐ENaC. Expression of iNOS increased, but NO was not detected. Both staphylococci caused a decrease in the intracellular Ca2+ concentration. S. aureus induced increased secretion of IL‐6, IL‐8, and transforming nuclear factor (TNF)‐α in a time‐dependent manner as compared with S. epidermidis. In conclusion, expression of ENaC, CFTR, and iNOS is modulated by exposure to S. aureus 90B083 and S. epidermidis 94B080. S. aureus is more potent in causing release of IL‐6, IL‐8, and TNF‐α by bronchial epithelial cells as compared with S. epidermidis. The mRNA expression for the mucus proteins MUC2, MUC5AC, and MUC5B could not be measured, neither in the presence nor in the absence of bacteria. 相似文献