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51.
E. Kevin Heist Jianping Chevalier Godtfred Holmvang Jagmeet P. Singh Patrick T. Ellinor David J. Milan Andre D’Avila Theofanie Mela Jeremy N. Ruskin Moussa Mansour 《Journal of interventional cardiac electrophysiology》2006,17(1):21-27
Objective Integration of 3-D electroanatomic mapping with Computed Tomographic (CT) and Magnetic Resonance (MR) imaging is gaining acceptance
to facilitate catheter ablation of atrial fibrillation. This is critically dependent on accurate integration of electroanatomic
maps with CT or MR images. We sought to examine the effect of patient- and technique-related factors on integration accuracy
of electroanatomic mapping with CT and MR imaging of the left atrium.
Materials and methods Sixty-one patients undergoing catheter-based atrial fibrillation (AF) ablation procedures were included. All patients underwent
cardiac CT (n = 11) or MR (n = 50) imaging, and image integration with real-time electroanatomic mapping of the aorta and left atrium (LA). CARTO-Merge
software (Biosense-Webster) was used to calculate the overall average accuracy of integration of electroanatomic points with
the CT and MR-derived reconstructions of the LA and aorta.
Results There was a significant correlation between LA size assessed by electroanatomic mapping (112 ± 31 ml) and average integration
error (1.9 ± 0.6 mm) (r = 0.46, p = 0.0003). There was also greater integration error for patients with LA volume ≥ 110 ml (n = 31) versus < 110 ml (n = 30) (p = 0.004). In contrast, there was no significant association between average integration error and paroxysmal versus persistent
AF, left ventricular ejection fraction, days from imaging to electroanatomic mapping, or images derived from CT versus MR.
Conclusions Patients with larger LA volume may be prone to greater error during integration of electroanatomic mapping with CT and MR
imaging. Strategies to reduce integration error may therefore be especially useful in patients with large LA volume. 相似文献
52.
Autologous bone marrow transplantation for childhood acute lymphoblastic leukaemia in second remission - long-term follow-up 总被引:2,自引:0,他引:2
Vaidya SJ Atra A Bahl S Pinkerton CR Calvagna V Horton C Milan S Shepherd V Brain C Treleaven J Powles R Tait D Meller ST 《Bone marrow transplantation》2000,25(6):599-603
From 1984 to 1996, 31 consecutive children without sibling donors, aged 5-19 years (median 8) with acute lymphoblastic leukaemia (ALL) in second complete remission (CR), received unpurged autologous bone marrow transplantation (ABMT) after melphalan and single fraction total body irradiation (TBI). ABMT was performed using fresh unmanipulated marrow harvested after standard reinduction and consolidation therapy 2-11 months (median 5) after relapse. With a median survival of 2.9 years the probability of survival for all patients in continuing second CR was 45.1% (95% CI, 24%-62%) after 5 years. Regimen-related and non-leukaemia mortality was 7% (95% CI, 2%-26%). The longest time to second relapse from ABMT was 3.1 years. Pituitary and gonadal dysfunction requiring hormonal replacement therapy occurred in the majority of long-term survivors. Twelve patients developed cataracts. ABMT with melphalan/single fraction TBI has proved an effective anti-leukaemia treatment with low regimen-related mortality but significant long-term morbidity. The current approach of allogeneic BMT from an unrelated donor when no sibling donor is available, following conditioning with cyclophosphamide/ fractionated TBI has resulted in a reduced relapse rate and improved short-term overall survival in the treatment of relapsed childhood ALL. However, long-term results are awaited. 相似文献
53.
Jan D. Marshall Jean Muller Gayle B. Collin Gabriella Milan Stephen F. Kingsmore Darrell Dinwiddie Emily G. Farrow Neil A. Miller Francesca Favaretto Pietro Maffei Hélène Dollfus Roberto Vettor Jürgen K. Naggert 《Human mutation》2015,36(7):660-668
Alström Syndrome (ALMS), a recessive, monogenic ciliopathy caused by mutations in ALMS1, is typically characterized by multisystem involvement including early cone‐rod retinal dystrophy and blindness, hearing loss, childhood obesity, type 2 diabetes mellitus, cardiomyopathy, fibrosis, and multiple organ failure. The precise function of ALMS1 remains elusive, but roles in endosomal and ciliary transport and cell cycle regulation have been shown. The aim of our study was to further define the spectrum of ALMS1 mutations in patients with clinical features of ALMS. Mutational analysis in a world‐wide cohort of 204 families identified 109 novel mutations, extending the number of known ALMS1 mutations to 239 and highlighting the allelic heterogeneity of this disorder. This study represents the most comprehensive mutation analysis in patients with ALMS, identifying the largest number of novel mutations in a single study worldwide. Here, we also provide an overview of all ALMS1 mutations identified to date. 相似文献
54.
Reto Burri Alexander Nater Takeshi Kawakami Carina F. Mugal Pall I. Olason Linnea Smeds Alexander Suh Ludovic Dutoit Stanislav Bure? Laszlo Z. Garamszegi Silje Hogner Juan Moreno Anna Qvarnstr?m Milan Ru?i? Stein-Are S?ther Glenn-Peter S?tre Janos T?r?k Hans Ellegren 《Genome research》2015,25(11):1656-1665
Speciation is a continuous process during which genetic changes gradually accumulate in the genomes of diverging species. Recent studies have documented highly heterogeneous differentiation landscapes, with distinct regions of elevated differentiation (“differentiation islands”) widespread across genomes. However, it remains unclear which processes drive the evolution of differentiation islands; how the differentiation landscape evolves as speciation advances; and ultimately, how differentiation islands are related to speciation. Here, we addressed these questions based on population genetic analyses of 200 resequenced genomes from 10 populations of four Ficedula flycatcher sister species. We show that a heterogeneous differentiation landscape starts emerging among populations within species, and differentiation islands evolve recurrently in the very same genomic regions among independent lineages. Contrary to expectations from models that interpret differentiation islands as genomic regions involved in reproductive isolation that are shielded from gene flow, patterns of sequence divergence (dxy and relative node depth) do not support a major role of gene flow in the evolution of the differentiation landscape in these species. Instead, as predicted by models of linked selection, genome-wide variation in diversity and differentiation can be explained by variation in recombination rate and the density of targets for selection. We thus conclude that the heterogeneous landscape of differentiation in Ficedula flycatchers evolves mainly as the result of background selection and selective sweeps in genomic regions of low recombination. Our results emphasize the necessity of incorporating linked selection as a null model to identify genome regions involved in adaptation and speciation.Uncovering the genetic architecture of reproductive isolation and its evolutionary history are central tasks in evolutionary biology. The identification of genome regions that are highly differentiated between closely related species, and thereby constitute candidate regions involved in reproductive isolation, has recently been a major focus of speciation genetic research. Studies from a broad taxonomic range, involving organisms as diverse as plants (Renaut et al. 2013), insects (Turner et al. 2005; Lawniczak et al. 2010; Nadeau et al. 2012; Soria-Carrasco et al. 2014), fishes (Jones et al. 2012), mammals (Harr 2006), and birds (Ellegren et al. 2012) contribute to the emerging picture of a genomic landscape of differentiation that is usually highly heterogeneous, with regions of locally elevated differentiation (“differentiation islands”) widely spread over the genome. However, the evolutionary processes driving the evolution of the differentiation landscape and the role of differentiation islands in speciation are subject to controversy (Turner and Hahn 2010; Cruickshank and Hahn 2014; Pennisi 2014).Differentiation islands were originally interpreted as “speciation islands,” regions that harbor genetic variants involved in reproductive isolation and are shielded from gene flow by selection (Turner et al. 2005; Soria-Carrasco et al. 2014). During speciation-with-gene-flow, speciation islands were suggested to evolve through selective sweeps of locally adapted variants and by hitchhiking of physically linked neutral variation (“divergence hitchhiking”) (Via and West 2008); gene flow would keep differentiation in the remainder of the genome at bay (Nosil 2008; Nosil et al. 2008). In a similar way, speciation islands can arise by allopatric speciation followed by secondary contact. In this case, genome-wide differentiation increases during periods of geographic isolation, but upon secondary contact, it is reduced by gene flow in genome regions not involved in reproductive isolation. In the absence of gene flow in allopatry, speciation islands need not (but can) evolve by local adaptation, but may consist of intrinsic incompatibilities sensu Bateson-Dobzhansky-Muller (Bateson 1909; Dobzhansky 1937; Muller 1940) that accumulated in spatially isolated populations.However, whether differentiation islands represent speciation islands has been questioned. Rather than being a cause of speciation, differentiation islands might evolve only after the onset of reproductive isolation as a consequence of locally accelerated lineage sorting (Noor and Bennett 2009; Turner and Hahn 2010; White et al. 2010; Cruickshank and Hahn 2014; Renaut et al. 2014), such as in regions of low recombination (Nachman 2002; Sella et al. 2009; Cutter and Payseur 2013). In these regions, the diversity-reducing effects of both positive selection and purifying selection (background selection [BGS]) at linked sites (“linked selection”) impact physically larger regions due to the stronger linkage among sites. The thereby locally reduced effective population size (Ne) will enhance genetic drift and hence inevitably lead to increased differentiation among populations and species.These alternative models for the evolution of a heterogeneous genomic landscape of differentiation are not mutually exclusive, and their population genetic footprints can be difficult to discern. In the cases of (primary) speciation-with-gene-flow and gene flow at secondary contact, shared variation outside differentiation islands partly stems from gene flow. In contrast, under linked selection, ancestral variation is reduced and differentiation elevated in regions of low recombination, while the remainder of the genome may still share considerable amounts of ancestral genetic variation and show limited differentiation. Many commonly used population genetic statistics do not capture these different origins of shared genetic variation and have the same qualitative expectations under both models, such as reduced diversity (π) and skews toward an excess of rare variants (e.g., lower Tajima''s D) in differentiation islands relative to the remainder of the genome. However, since speciation islands should evolve by the prevention or breakdown of differentiation by gene flow in regions not involved in reproductive isolation, substantial gene flow should be detectable in these regions (Cruickshank and Hahn 2014) and manifested in the form of reduced sequence divergence (dxy) or as an excess of shared derived alleles in cases of asymmetrical gene flow (Patterson et al. 2012). Under linked selection, predictions are opposite for dxy (Cruickshank and Hahn 2014), owing to reduced ancestral diversity in low-recombination regions. Further predictions for linked selection include positive and negative relationships of recombination rate with genetic diversity (π) and differentiation (FST), respectively, and inverse correlations of the latter two with the density of targets for selection. Finally, important insights into the nature of differentiation islands may be gained by studying the evolution of differentiation landscapes across the speciation continuum. Theoretical models and simulations of speciation-with-gene-flow predict that after an initial phase during which differentiation establishes in regions involved in adaptation, differentiation should start spreading from these regions across the entire genome (Feder et al. 2012, 2014; Flaxman et al. 2013).Unravelling the processes driving the evolution of the genomic landscape of differentiation, and hence understanding how genome differentiation unfolds as speciation advances, requires genome-wide data at multiple stages of the speciation continuum and in a range of geographical settings from allopatry to sympatry (Seehausen et al. 2014). Although studies of the speciation continuum are emerging (Hendry et al. 2009; Kronforst et al. 2013; Shaw and Mullen 2014, and references therein), empirical examples of genome differentiation at multiple levels of species divergence remain scarce (Andrew and Rieseberg 2013; Kronforst et al. 2013; Martin et al. 2013), and to our knowledge, have so far not jointly addressed the predictions of alternative models for the evolution of the genomic landscape of differentiation. In the present study, we implemented such a study design encompassing multiple populations of four black-and-white flycatcher sister species of the genus Ficedula (Fig. 1A,B; Supplemental Fig. S1; for a comprehensive reconstruction of the species tree, see Nater et al. 2015). Previous analyses in collared flycatcher (F. albicollis) and pied flycatcher (F. hypoleuca) revealed a highly heterogeneous differentiation landscape across the genome (Ellegren et al. 2012). An involvement of gene flow in its evolution would be plausible, as hybrids between these species occur at low frequencies in sympatric populations in eastern Central Europe and on the Baltic Islands of Gotland and Öland (Alatalo et al. 1990; Sætre et al. 1999), although a recent study based on genome-wide markers identified no hybrids beyond the F1 generation (Kawakami et al. 2014a). Still, gene flow from pied into collared flycatcher appears to have occurred (Borge et al. 2005; Backström et al. 2013; Nadachowska-Brzyska et al. 2013) despite premating isolation (for review, see Sætre and Sæther 2010), hybrid female sterility (Alatalo et al. 1990; Tegelström and Gelter 1990), and strongly reduced long-term fitness of hybrid males (Wiley et al. 2009). Atlas flycatcher (F. speculigera) and semicollared flycatcher (F. semitorquata) are two closely related species, which have been less studied, but may provide interesting insights into how genome differentiation evolves over time. Here, we take advantage of this system to identify the processes underlying the evolution of differentiation islands based on the population genetic analysis of whole-genome resequencing data of 200 flycatchers.Open in a separate windowFigure 1.A recurrently evolving genomic landscape of differentiation across the speciation continuum in Ficedula flycatchers. (A) Species’ neighbor-joining tree based on mean genome-wide net sequence divergence (dA). The same species tree topology was inferred with 100% bootstrap support from the distribution of gene trees under the multispecies coalescent (Supplemental Fig. S1). (B) Map showing the locations of population sampling and approximate species ranges. (C) Population genomic parameters along an example chromosome (Chromosome 4A) (see Supplemental Figs. S2, S4 for all chromosomes). Color codes for specific–specific parameters: (blue) collared; (green) pied; (orange) Atlas; (red) semicollared. Color codes for dxy: (green) collared-pied; (light blue) collared-Atlas; (blue) collared-semicollared; (orange) pied-Atlas; (red) pied-semicollared; (black) Atlas-semicollared. For differentiation within species, comparisons with the Italian (collared) and Spanish (pied) populations are shown. Color codes for FST within collared flycatchers: (cyan) Italy–Hungary; (light blue) Italy–Czech Republic; (dark blue) Italy–Baltic. Color codes for FST within pied flycatchers: (light green) Spain–Sweden; (green) Spain–Czech Republic; (dark green) Spain–Baltic. (D) Distributions of differentiation (FST) from collared flycatcher along the speciation continuum. Distributions are given separately for three autosomal recombination percentiles (33%; 33%–66%; 66%–100%) corresponding to high (>3.4 cM/Mb, blue), intermediate (1.3–3.4 cM/Mb, orange), and low recombination rate (0–1.3 cM/Mb, red), and the Z Chromosome (green). Geographically close within-species comparison: Italy–Hungary. Comparisons within species include the geographically close Italian and Hungarian populations (within [close]), and the geographically distant Italian and Baltic populations (within [far]). Geographically far within-species comparison: Italy–Baltic. (E) Differentiation from collared flycatcher along an example chromosome (Chromosome 11) (see Supplemental Fig. S3 for all chromosomes). Color codes for between-species comparisons: (green) pied; (orange) Atlas; (red) semicollared; (dark red) red-breasted; (black) snowy-browed flycatcher. Color codes for within-species comparisons: (cyan) Italy–Hungary; (blue) Italy–Baltic. Flycatcher artwork in panel A courtesy of Dan Zetterström. 相似文献
55.
56.
Russo MW LaPointe-Rudow D Teixeira A Guarrera J Dove LM Gaglio P Emond JC Kinkhabwala M Brown RS 《Journal of clinical gastroenterology》2004,38(9):810-814
OBJECTIVES: The safety of donors is paramount in adult living donor liver transplantation. Our goal is to compare the pattern of recovery of hepatic synthetic function and aminotransferases in healthy adult donors with and without complications. METHODS: We reviewed 47 consecutive patients undergoing right donor hepatectomy at our center. Laboratory data were collected through the first 2 postoperative weeks and results from donors with and without complications were compared. RESULTS: Donor morbidity was 25% and there were no donor deaths. Total bilirubin peaked on postoperative day 3, whereas aminotransferases and international normalized ratio peaked on postoperative day 1. Peak total bilirubin was higher in patients with fluid collections (n = 7) compared with those without fluid collections (n = 40), 4.6 mg/dL and 2.3 mg/dL, respectively, P = 0.02. On postoperative day 3 the peak total bilirubin was greater than 3.0 mg/dL in 86% of donors with fluid collections and 15% of donors without fluid collections, (P = 0.0005) whereas aminotransferases and alkaline phosphatase were not significantly different between these 2 groups. CONCLUSIONS: After right donor hepatectomy a total bilirubin greater than 3.0 mg/dL on postoperative day 3 should prompt an evaluation for a fluid collection, even if other liver tests are normal or declining. 相似文献
57.
R. Ferrari G. La Canna R. Giubbini E. Milan C. Ceconi F. de Giuli P. Berra O. Alfieri O. Visioli 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》1994,8(Z2):371-380
Left ventricular dysfunction is in most cases the consequence of myocardial ischemia. It may occur transiently during an attack of angina and usually it is reversible. It may persist over hours or even days in patients after an episode of ischemia followed by reperfusion, leading to the so-called condition of stunning. In patients with persistent limitation of coronary flow, left ventricular dysfunction may be present over months and years, or indefinitely in subjects with fibrosis, scar formation, and remodeling after myocardial infarction. Bowever, chronic left ventricular dysfunction does not mean permanent or irreversible cell damage. Bypoperfused myocytes can remain viable but akinetic. This type of dysfunction has been calledhibernating myocardium. The dysfunction due to hibernation can be partially or completely restored to normal by reperfusion. It is, therefore, important to clinically recognize a hibernating myocardium. In the present article we evaluate stunning and hibernation with respect to clinical decision making and, when possible, we refer to our ongoing clinical experience. 相似文献
58.
Bures J Kabelác K Kopácová M Vorísek V Siroký M Palicka V Rejchrt S 《Hepato-gastroenterology》2008,55(85):1492-1496
BACKGROUND/AIMS: The aim of this prospective study was to characterize gastric myoelectrical activity in patients with Roux-en-Y reconstruction after previous Billroth gastrectomy. METHODOLOGY: Thirteen patients entered the study (6 men and 7 women, aged 35-57). The mean time from Roux-en-Y reconstruction to electrogastrography (EGG) recording was 5 years. Surface cutaneous EGG was recorded using a Digitrapper EGG in the morning both fasting and after a standard solid test meal. All patients assessed their dyspeptic symptoms at the time of EGG in a semi-quantitative subjective scale. RESULTS: EGG was abnormal in all studied patients (but one postprandial recording). Dyspepsia was not meal-related and was not more severe in Helicobacter pylori positive patients. There was a significant negative correlation between time from Roux-en-Y reconstruction to EGG recording and bradygastria percent activity, both fasted and postprandial (r = -0.576; p = 0.0022). There was an inverse trend between severity of dyspepsia and normal slow-wave rhythm percent activity. Older patients tended to have more severe dyspepsia. CONCLUSIONS: The results of this study suggest that abnormal EGG recording is associated with dyspepsia in patients after Roux-en-Y reconstruction. 相似文献
59.
Olga Brantová Markéta Tesařová Hana Hansíková Milan Elleder Jiří Zeman 《Ultrastructural pathology》2013,37(4):239-245
Mitochondrial disorders represent a heterogeneous group of multisystem diseases with extreme variability in clinical phenotype. The diagnosis of mitochondrial disorders relies heavily on extensive biochemical and molecular analyses combined with morphological studies including electron microscopy. Although muscle is the tissue of choice for electron microscopic studies, the authors investigated cultivated human skin fibroblasts (HSF) harboring 3 different pathologic mtDNA mutations: 3243A > G, 8344A > G, 8993T > G. They addressed to the possibility of whether mtDNA mutations influence mitochondrial morphology in HSF and if ultrastructural changes of mitochondria may be used for differential diagnostics of mitochondrial disorders caused by mtDNA mutations. Ultrastructural analysis of patients' HSF revealed a heterogeneous mixture of mainly abnormal, partially swelling mitochondria with unusual and sparse cristae. The most characteristic cristal abnormalities were heterogeneity in size and shapes or their absence. Typical filamentous and branched mitochondria with numerous cristae as appeared in control HSF were almost not observed. In all lines of cultured HSF with various mtDNA mutations, similar ultrastructural abnormalities and severely changed mitochondrial interior were found, although no alterations in function and amount of OXPHOS were detected by routinely used biochemical methods in two lines of cultured HSF. This highlights the importance of morphological analysis, even in cultured fibroblasts, in diagnostics of mitochondrial disorders. 相似文献
60.
Ana Katušić Iris Žunić Išasegi Milan Radoš Marina Raguž Ruža Grizelj Fabrizio Ferrari Ivica Kostović 《Brain & development》2021,43(3):363-371
AimTo explore the relationships between transient structural brain patterns on MRI at preterm and at term-equivalent age (TEA) as a predictor of general movements (GMs) and motor development at 1-year corrected age (CA) in very preterm infants.MethodsIn this prospective study, 30 very preterm infants (median = 28wks; 16 males) had structural magnetic resonance imaging (MRI) at preterm (median = 31wks + 6d) and at TEA (median = 40wks) and neuromotor assessments. The quality of GMs was assessed by Prechtl’s general movements assessment and a detailed analysis of the motor repertoire was performed by calculating a motor optimality score (MOS), both at term age and at 3 months post-term. Motor development at 1-year CA was evaluated with the Infant Motor Profile (IMP). Associations between qualitative MRI findings and neuromotor scores were investigated.ResultsAbnormal GMs and low motor performance at 1-year CA were associated with the poor visibility of transient structural pattern, that is with sagittal strata.InterpretationTransient structural MRI pattern, sagittal strata, at preterm age is related to the quality of GMs and later motor development in preterm infants. This transient fetal brain compartment may be considered as a component of neurobiological basis for early neuromotor behavior, as expressed by GMs. 相似文献