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201.
Blood vessels and other anatomic objects in the human body can be described as trees of branching tubes. The focus of this paper is the extraction of the branching geometry in three-dimensional, as well as the extraction of the tubes themselves, via skeletons computed as cores. Cores are height ridges of a graded measure of medial strength called medialness, which measures how much a given location resembles the middle of an object as indicated by image intensities. Object bifurcations are detected using an affine-invariant corner detector and computations on the core's medialness values. The methods presented in this paper are evaluated on synthetic images of branching tubular objects as well as on blood vessels in head MR angiogram data. Results show impressive resistance to noise and the ability to detect branches spanning a variety of widths and branching angles. An extension that allows cores to extract general branching structures, not only branching tubes, is introduced. 相似文献
202.
Correcting errors and proofreading are crucial in a post-genomic era, when DNA sequences are already part of an effective medical screening and treatments. SNPs genotyping of complex human genes can lead to questionable associations if not properly handled. Here, we report about a spurious (reitered) association between FCGR2B genetic polymorphisms and systemic lupus erythematosus. 相似文献
203.
Grad YH Lipsitch M Feldgarden M Arachchi HM Cerqueira GC Fitzgerald M Godfrey P Haas BJ Murphy CI Russ C Sykes S Walker BJ Wortman JR Young S Zeng Q Abouelleil A Bochicchio J Chauvin S Desmet T Gujja S McCowan C Montmayeur A Steelman S Frimodt-Møller J Petersen AM Struve C Krogfelt KA Bingen E Weill FX Lander ES Nusbaum C Birren BW Hung DT Hanage WP 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(8):3065-3070
The degree to which molecular epidemiology reveals information about the sources and transmission patterns of an outbreak depends on the resolution of the technology used and the samples studied. Isolates of Escherichia coli O104:H4 from the outbreak centered in Germany in May-July 2011, and the much smaller outbreak in southwest France in June 2011, were indistinguishable by standard tests. We report a molecular epidemiological analysis using multiplatform whole-genome sequencing and analysis of multiple isolates from the German and French outbreaks. Isolates from the German outbreak showed remarkably little diversity, with only two single nucleotide polymorphisms (SNPs) found in isolates from four individuals. Surprisingly, we found much greater diversity (19 SNPs) in isolates from seven individuals infected in the French outbreak. The German isolates form a clade within the more diverse French outbreak strains. Moreover, five isolates derived from a single infected individual from the French outbreak had extremely limited diversity. The striking difference in diversity between the German and French outbreak samples is consistent with several hypotheses, including a bottleneck that purged diversity in the German isolates, variation in mutation rates in the two E. coli outbreak populations, or uneven distribution of diversity in the seed populations that led to each outbreak. 相似文献
204.
205.
Marian Plotkin Srirangam Ramanujam Vaibavi Abdul Jalil Rufaihah Venkateswaran Nithya Jing Wang Yonatan Shachaf Theo Kofidis Dror Seliktar 《Biomaterials》2014
This study compares the effect of four injectable hydrogels with different mechanical properties on the post-myocardial infarction left ventricle (LV) remodeling process. The bioactive hydrogels were synthesized from Tetronic-fibrinogen (TF) and PEG–fibrinogen (PF) conjugates; each hydrogel was supplemented with two levels of additional cross-linker to increase the matrix stiffness as measured by the shear storage modulus (G′). Infarcts created by ligating the left anterior descending coronary artery in a rodent model were treated with the hydrogels, and all four treatment groups showed an increase in wall thickness, arterial density, and viable cardiac tissue in the peri-infarct areas of the LV. Echocardiography and hemodynamics data of the PF/TF treated groups showed significant improvement of heart function associated with the attenuated effects of the remodeling process. Multi-factorial regression analysis indicated that the group with the highest modulus exhibited the best rescue of heart function and highest neovascularization. The results of this study demonstrate that multiple properties of an injectable bioactive biomaterial, and notably the matrix stiffness, provide the multifaceted stimulation necessary to preserve cardiac function and prevent adverse remodeling following a heart attack. 相似文献
206.
207.
Shewit Kalayou Mekonnen Haileselassie Gebremedhin Gebre-egziabher Tsegay Tiku'e Samson Sahle Habtamu Taddele Mussie Ghezu 《Asian Pacific Journal of Tropical Biomedicine》2012,2(7):516-522
Objective
To screen the antibacterial activity of nine ethnoveterinary plants traditionally used for the treatment of mastitis, wound and gastrointestinal complications.Methods
Hydroalcoholic exctracts of medicinal plants namely, Achyranthes aspera (A. aspera) L. (Family Asparagaceae), Ficus caria (F. caria) (Family Moraceae), Malvi parviflora (M. parviflora) (Family Malvaceae), Vernonia species (V. species) (local name Alakit, Family Asteraceae), Solanum hastifolium (S. hastifolium) (Family Solanaceae), Calpurinia aurea (C. aurea) (Ait) Benth (Family Fabaceae), Nicotiana tabacum (N. tabacum) L. (Family Solanaceae), Ziziphus spina-christi (Z. spina-christi) (Family Rhamnaceae), Croton macrostachys (C. macrostachys) (Family Euphorbiaceae), were screened against clinical bacterial isolates of veterinary importance from October 2007 to April 2009. The antibacterial activity was tested using disc diffusion at two concentrations (200 mg/mL and 100 mg/mL) and broth dilution methods using 70% methanol macerated leaf extracts.Results
With the exception of S. hastifolium all plant extracts exhibited antibacterial activity. Among the medicinal plants tested C. aurea, C. macrostachyus, A. aspera, N. tabacum and vernonia species (Alakit) showed the most promising antimicrobial properties.Conclusions
It can be concluded that many of the tested plants have antibacterial activity and supports the traditional usage of the plants for mastitis, wound and gastrointestinal complications treatment. Further studies into their toxicity and phytochemistry is advocated. 相似文献208.
A remarkable act of memory entails binding different forms of information. We focus on the timeless question of how the bound engram is accessed such that its component features-item and context-are extracted. To shed light on this question, we investigate the dynamics between brain structures that together mediate the binding and extraction of item and context. Converging evidence has implicated the Parahippocampal cortex (PHc) in contextual processing, the Perirhinal cortex (PRc) in item processing, and the hippocampus in item-context binding. Effective connectivity analysis was conducted on fMRI data gathered during retrieval on tests that differ with regard to the to-be-extracted information. Results revealed that recall is initiated by context-related PHc activity, followed by hippocampal item-context engram activation, and completed with retrieval of the study-item by the PRc. The reverse path was found for recognition. We thus provide novel evidence for dissociative patterns of item-context unbinding during retrieval. 相似文献
209.
Relapsing polychondritis (RP) and familial Mediterranean fever (FMF) are systemic inflammatory disorders with seemingly distinct
genetic and pathophysiologic mechanisms. An association between these disorders has been described based on a single case
report with few clinical details available. We recently encountered a patient with biopsy-proven RP and genetically confirmed
FMF. Following identification of this individual, we conducted a retrospective review of all cases of RP in our institution
from 2000–2009 and identified one additional patient with RP who is also a genetic heterozygote for FMF. These cases highlight
the previously reported but sparsely documented relationship between these seemingly separate disorders. 相似文献
210.
Butbul Aviel Y Mandel H Avitan Hersh E Reuven B Orly EA Anthony L Riva B 《Pediatric rheumatology online journal》2012,10(1):18
ABSTRACT: INTRODUCTION: Prolidase deficiency (PD) is a rare autosomal recessive disorder which may have a wide spectrum of clinical features. These features include a characteristic facies, cognitive impairment, rashes or skin ulceration, splenomegaly, recurrent infections involving mainly the respiratory system, and iminodipeptiduria. The disorder is caused by a mutation in the PEPD gene. OBJECTIVE: To describe a cohort of unrelated PD patients from Northern Israel whose inborn error of metabolism was associated with systemic lupus erythematosus (SLE) and to identify in the medical literature all PD cases mimicked by and/or associated with SLE. METHODS: Three patients with PD associated with SLE were clinically, biochemically and genetically investigated. These patients were from 3 unrelated consanguineous families residing in Northern Israel. A computer-assisted (PubMed) search of the medical literature from 1975 to 2011 was performed using the following key words: Prolidase deficiency, SLE, and systemic lupus erythematosus. RESULTS: An association between PD and SLE was found in 10 PD patients. These 10 patients included three from our cohort of 23 PD patients, and seven out of just under 70 PD patients previously reported in the literature. CONCLUSION: The present findings underscore the relatively high incidence of the association between SLE and PD, suggesting that this association may not be coincidental. The phenotypic similarities between SLE and PD might suggest that the PEPD gene constitutes a modifier gene or a genetic risk factor in the causation of SLE. 相似文献