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41.
C. P. Mendes L. P. Samorano S. S. Alessi M. M. S. Nico 《Clinical and experimental dermatology》2014,39(6):728-730
Divided or kissing naevi are located on adjacent parts of the body that are separated during embryogenesis. Divided naevus of the penis (DNP) is exceedingly rare, with < 15 cases reported in the English language literature. Divided penile naevi affect the glans penis and inner foreskin, which are anatomical structures believed to have a common embryological origin. We report the clinical, dermoscopic and histopathological findings of two children with DNP. To our knowledge, this is the first report of patients with DNP seen in South America, and the first in which dermoscopic findings are discussed; these included a large globular pattern in one patient, and homogeneous, streaked and globular patterns in the other. 相似文献
42.
Nico Bauer Robert J. Brecha Gunnar Luderer 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(42):16805-16810
The events of March 2011 at the nuclear power complex in Fukushima, Japan, raised questions about the safe operation of nuclear power plants, with early retirement of existing nuclear power plants being debated in the policy arena and considered by regulators. Also, the future of building new nuclear power plants is highly uncertain. Should nuclear power policies become more restrictive, one potential option for climate change mitigation will be less available. However, a systematic analysis of nuclear power policies, including early retirement, has been missing in the climate change mitigation literature. We apply an energy economy model framework to derive scenarios and analyze the interactions and tradeoffs between these two policy fields. Our results indicate that early retirement of nuclear power plants leads to discounted cumulative global GDP losses of 0.07% by 2020. If, in addition, new nuclear investments are excluded, total losses will double. The effect of climate policies imposed by an intertemporal carbon budget on incremental costs of policies restricting nuclear power use is small. However, climate policies have much larger impacts than policies restricting the use of nuclear power. The carbon budget leads to cumulative discounted near term reductions of global GDP of 0.64% until 2020. Intertemporal flexibility of the carbon budget approach enables higher near-term emissions as a result of increased power generation from natural gas to fill the emerging gap in electricity supply, while still remaining within the overall carbon budget. Demand reductions and efficiency improvements are the second major response strategy. 相似文献
43.
44.
Elma J. Gussenhoven Meindert A. Taams Jos Roelandt Klaas Bom Jan Honkoop Nico de Jong Kees M. Ligtvoet 《The International Journal of Cardiac Imaging》1987,2(4):231-239
Summary The diagnostic value of oesophageal echocardiography is most striking in patients in whom precordial studies are of inadequate quality or fail to establish a definitive diagnosis. Oesophageal studies have excellent image quality, can be completed within 10 minutes without complications and, in most instances, enables the clinical question to be answered. In 50 patients referred for suspected thoracic aorta pathology, oesophageal echocardiography correctly excluded or diagnosed the type of aortic dissection, aortic aneurysm or the site of coarctation. Of 35 patients referred with suspected infective endocarditis, oesophageal echocardiography revealed complications in 18 patients, including vegetation, mycotic aneurysm, abscess or chordal rupture. Oesophageal echocardiography is extremely helpful to visualize intracardiac mass lesions. In 27 patients with a history of systemic or pulmonary embolism, the technique confirmed the presence, size and position of a mass lesion in 11 patients. Oesophageal color Doppler flow imaging further expands the diagnostic capabilities, particularly in patients with mitral valve prosthesis. Our experience indicates that oesophageal echocardiography significantly extends the diagnostic potential of echocardiography. Detailed knowledge of cardiothoracic anatomy and its pathologic sequelae is, however, a prerequisite for the efficient and safe application of this method. 相似文献
45.
Sheila Oliveira Angelo Ravelli Angela Pistorio Esteban Castell Clara Malattia Anne Marie Prieur Claudia Saad‐Magalhães Kevin J. Murray Sang‐Cheol Bae Rik Joos Ivan Foeldvari Carolina Duarte‐Salazar Nico Wulffraat Pekka Lahdenne Pavla Dolezalova Jaime de Inocencio Florence Kanakoudi‐Tsakalidou Michael Hofer Irina Nikishina Huri Ozdogan Philip J. Hashkes Jeanne M. Landgraf Alberto Martini Nicolino Ruperto 《Arthritis care & research》2007,57(1):35-43
Objective
To investigate the proxy‐reported health‐related quality of life (HRQOL) and its determinants in patients with juvenile idiopathic arthritis (JIA).Methods
In this multinational, multicenter, cross‐sectional study, HRQOL of patients with JIA was assessed through the Child Health Questionnaire (CHQ) and was compared with that of healthy children of similar age from the same geographic area. Potential determinants of HRQOL included demographic data, physician's and parent's global assessments, measures of joint inflammation, Childhood Health Assessment Questionnaire (CHAQ), and erythrocyte sedimentation rate.Results
A total of 6,639 participants (3,324 with JIA and 3,315 healthy) were enrolled from 32 countries. The mean ± SD physical and psychosocial summary scores of the CHQ were significantly lower in patients with JIA than in healthy children (physical: 44.5 ± 10.6 versus 54.6 ± 4.0, P < 0.0001; psychosocial: 47.6 ± 8.7 versus 51.9 ± 7.5, P < 0.0001), with the physical well‐being domain being most impaired. Patients with persistent oligoarthritis had better HRQOL compared with other subtypes, whereas HRQOL was similar across patients with systemic arthritis, polyarthritis, and extended oligoarthritis. A CHAQ score >1 and a pain intensity rating >3.4 cm on a 10‐cm visual analog scale were the strongest determinants of poorer HRQOL in the physical and psychosocial domains, respectively.Conclusion
We found that patients with JIA have a significant impairment of their HRQOL compared with healthy peers, particularly in the physical domain. Physical well‐being was mostly affected by the level of functional impairment, whereas the intensity of pain had the greatest influence on psychosocial health. 相似文献46.
Geier A Zollner G Dietrich CG Wagner M Fickert P Denk H van Rooijen N Matern S Gartung C Trauner M 《Hepatology (Baltimore, Md.)》2005,41(3):470-477
Cholestatic liver injury is associated not only with accumulation of bile acids but also with activation of proinflammatory cytokines. Common bile duct ligation (CBDL) induces sustained downregulation of the Na(+)/taurocholate cotransporter (Ntcp) in rodent liver. Although repression of Ntcp during endotoxemia is cytokine mediated, it is unclear whether inflammatory cytokines contribute to this downregulation in obstructive cholestasis. Cytokine inactivation in CBDL rats and mice was either performed directly with tumor necrosis factor alpha (etanercept) or interleukin 1 beta inactivation (anakinra/AMG 719) or indirectly Kupffer cell depletion via intraperitoneal administration of liposome-encapsulated dichloromethylene bisphosphonate. Protein and messenger RNA (mRNA) expression of Ntcp and short heterodimer partner (SHP) were analyzed via Western and Northern blotting. Key regulators of Ntcp (hepatocyte nuclear factor 1 alpha [HNF-1alpha], HNF-4alpha, retinoid X receptor alpha [RXRalpha]:retinoic acid receptor alpha [RARalpha]) were studied via electrophoretic mobility shift analysis and nuclear Western blot analysis. Both methods of cytokine inactivation failed to maintain Ntcp protein or mRNA expression within 3 days after CBDL in either rats or mice (20%-40% of sham controls), while SHP mRNA expression increased three- to five-fold. Decreased nuclear HNF-1alpha and HNF-4alpha protein levels (45% and 60% of sham controls, respectively) and HNF-1alpha binding activity (32% of sham controls) were not restored during cytokine inactivation after CBDL, indicating cytokine-independent mechanisms of Ntcp regulation. RXRalpha:RARalpha binding remained unchanged in all experimental conditions. In conclusion, during obstructive cholestasis accumulating bile acids per se, without major contribution of cytokines, leads to downregulation of Ntcp via repression of HNF-1alpha and HNF-4alpha. 相似文献
47.
Background
The worldwide spread of multidrug-resistant Gram-negative bacteria (MDR-GN) continues. Treatment options for infections caused by MDR-GN remain scarce and only few new substances are currently in clinical phase II/III studies or have already been granted market approval.Objectives
To provide an overview about current data on new β?lactam antibiotics and β?lactamase inhibitor combinations, respectively. New macrolides, ketolides and aminoglycosides are not addressed.Materials and methods
Selective literature research regarding published data on ceftazidim/avibactam, ceftolozan/tazobactam, imipenem/cilastatin?+?relebactam, meropenem/vaborbactam, aztreonam/avibactam and cefiderocol, as well as registered trials.Results
The development of new antimicrobials for the treatment of MDR-GN infections offers new options for attending physicians. β?Lactamase producers are inhibited by these new substances, though with varying efficacy; however, there are still no adequate treatment options for metallo-β-lactamase (MBL) producers.Conclusions
Clinical data are still indifferent and come from heterogeneous patient collectives. Direct comparisons with established treatment strategies, such as the “last-resort use” of polymyxins are hardly possible. Cases of early development of resistance have already been described. Finally, the importance of toxicity and optimal dosing—in organ failure or organ replacement procedures such as dialysis—remain unclear.48.
49.
Kaluzay J Vandenberghe K Fontaine D Ganame J Anné W Van der Merwe N Van de Werf F Heidbüchel H 《International journal of cardiology》2005,98(3):431-437
BACKGROUND: Determination of ST-segment deviation (STdev) and its resolution (STR) by reperfusion strategies have become important tools in the assessment of patients with acute myocardial infarction (AMI). STdev has been measured at different time-points, i.e. at 20-80 ms after the J-point. There are no data comparing STR at different time-points. METHODS AND RESULTS: STdev was measured using a new computer-assisted workflow. The intraclass correlation coefficients (ICC) for validity and agreement vs. classical manual measurements (n=1020) were both 0.996 (p<0.0001). The reliability indices were 0.991 (95% CI 0.990-0.992) for the manual vs. 0.995 (95% CI 0.995-0.996) for the computer-assisted method, indicating superiority of the latter. 12-lead STdev were determined on ECGs before (baseline) and 180 min after start of thrombolytic therapy, measured both at the J-point (STdev(J)) and 20 ms after the J-point (STdev(J20); n=2400). STdev(J20) was on average 0.01+/-0.03 mV higher than STdev(J) (p<0.0001) with a tendency towards larger differences for higher ST-elevations (p<0.001). Although the average STR calculated from STdev(J20) and STdev(J) was not statistically different in any infarct location group, in 26% of the patients the difference was >10%, and 11% of the patients were classified into another ST-resolution group. Analysing STdev only in the single lead with the highest ST-elevation at baseline (a simplified measurement which may eliminate the confounding effect of ST-depressions) showed an even higher classification discordance (14% of the patients). CONCLUSIONS: The time-point of STdev measurement is an important variable to be accounted for when evaluating ST resolution data. Uncontrolled extrapolation of classification schemes based on STdev(J20) to other time-points cannot be justified. 相似文献
50.
Yo Suzuki Nacyra Assad-Garcia Maxim Kostylev Vladimir N. Noskov Kim S. Wise Bogumil J. Karas Jason Stam Michael G. Montague Timothy J. Hanly Nico J. Enriquez Adi Ramon Gregory M. Goldgof R. Alexander Richter Sanjay Vashee Ray-Yuan Chuang Elizabeth A. Winzeler Clyde A. Hutchison III Daniel G. Gibson Hamilton O. Smith John I. Glass J. Craig Venter 《Genome research》2015,25(3):435-444
The availability of genetically tractable organisms with simple genomes is critical for the rapid, systems-level understanding of basic biological processes. Mycoplasma bacteria, with the smallest known genomes among free-living cellular organisms, are ideal models for this purpose, but the natural versions of these cells have genome complexities still too great to offer a comprehensive view of a fundamental life form. Here we describe an efficient method for reducing genomes from these organisms by identifying individually deletable regions using transposon mutagenesis and progressively clustering deleted genomic segments using meiotic recombination between the bacterial genomes harbored in yeast. Mycoplasmal genomes subjected to this process and transplanted into recipient cells yielded two mycoplasma strains. The first simultaneously lacked eight singly deletable regions of the genome, representing a total of 91 genes and ∼10% of the original genome. The second strain lacked seven of the eight regions, representing 84 genes. Growth assay data revealed an absence of genetic interactions among the 91 genes under tested conditions. Despite predicted effects of the deletions on sugar metabolism and the proteome, growth rates were unaffected by the gene deletions in the seven-deletion strain. These results support the feasibility of using single-gene disruption data to design and construct viable genomes lacking multiple genes, paving the way toward genome minimization. The progressive clustering method is expected to be effective for the reorganization of any mega-sized DNA molecules cloned in yeast, facilitating the construction of designer genomes in microbes as well as genomic fragments for genetic engineering of higher eukaryotes.Complexities of natural biological systems make it difficult to understand and define precisely the roles of individual genes and their integrated functions. The use of model organisms with a relatively small number of genes enables the isolation of core biological processes from their complex regulatory networks for extensive characterization. However, even the simplest natural microbes contain many genes of unknown function, as well as genes that can be singly or simultaneously deleted without any noticeable effect on growth rate in a laboratory setting (Hutchison et al. 1999; Glass et al. 2006; Posfai et al. 2006). Ill-defined genes and those mediating functional redundancies both compound the challenge of understanding even the simplest life forms.Toward generating a minimal cell where every gene is essential for the axenic viability of the organism, we are pursuing strategies to reduce the 1-Mb genome of Mycoplasma mycoides JCVI-syn1.0 (Gibson et al. 2010). Because we can (1) introduce this genome into yeast and maintain it as a plasmid (Benders et al. 2010; Karas et al. 2013a); and (2) “transplant” the genome from yeast into mycoplasma recipient cells (Lartigue et al. 2009), genetic tools in yeast are available for reducing this bacterial genome. Several systems offer advanced tools for bacterial genome engineering. Here we further exploit distinctive features of yeast for this purpose.Methods for serially replacing genomic regions with selectable markers are limited by the number of available markers. One effective approach is to reuse the same marker after precise and scarless marker excision (Storici et al. 2001). We have previously used a self-excising marker (Noskov et al. 2010) six times in yeast to generate a JCVI-syn1.0 genome lacking all six restriction systems (JCVI-syn1.0 ∆1-6) (Karas et al. 2013a). Despite the advantages of scarless engineering, sequential procedures are time-consuming. When applied to poorly characterized genes with the potential to interact with other genes, some paths for multigene knockout may lead to dead ends that result from synergistic mutant phenotypes. When a dead end is reached, sequentially returning to a previous genome in an effort to find a detour to a viable higher-order multimutant may be prohibitively time-consuming.An alternative approach to multigene engineering, available in yeast, is to prepare a set of single mutants and combine the deletions into a single strain via cycles of mating and meiotic recombination (Fig. 1A; Pinel et al. 2011; Suzuki et al. 2011, 2012). With a green fluorescent protein (GFP) reporter gene inserted in each deletion locus, the enrichment of higher-order yeast deletion strains in the meiotic population can be accomplished using flow cytometry. Here we apply this method to the JCVI-syn1.0 ∆1-6 exogenous, bacterial genome harbored in yeast to nonsequentially assemble deletions for genes predicted to be individually deletable based on biological knowledge or transposon-mediated disruption data. The functional identification of simultaneously deletable regions is expected to accelerate the effort to construct a minimal genome.Open in a separate windowFigure 1.Progressive clustering of deleted genomic segments. (A) Scheme of the method. Light blue oval represents a bacterial cell. Black ring or horizontal line denotes a bacterial genome, with the orange box indicating the yeast vector used as a site for linearization and recircularization. Gray shape denotes a yeast cell. Green dot in the genome indicates a deletion replaced with a GFP marker. (B) Map of deleted regions. Orange box indicates the yeast vector sequence used for genome linearization and recircularization. Green boxes indicate regions deleted in multimutant mycoplasma strains. Blue boxes denote restriction modification (RM) systems that are also deleted in the strains. (C) Pulsed-gel electrophoresis result for deleted genomes. The starting strain was the JCVI-syn1.0 ∆1–6 strain (1062 kb). Two strains were analyzed for each design of simultaneous deletion (962 kb for eight-deletion or 974 kb for seven-deletion genome). Ladder is a set of yeast chromosomes (New England BioLabs). (D) GFP-RFP ratio sorting result. Standard sorting was compared with sorting based on a GFP-RFP ratio (Methods). 相似文献