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151.
Maarten W. Barentsz Hester Wessels Paul J. van Diest Ruud M. Pijnappel Carmen C. van der Pol Arjen J. Witkamp Maurice A. A. J. van den Bosch Helena M. Verkooijen 《PloS one》2014,9(7)
Background
Same-day diagnosis based on histology is increasingly being offered to patients suspected of breast cancer. We evaluated to which extent same-day diagnosis affected diagnostic accuracy and patients'' anxiety levels during the diagnostic phase.Patients and methods
All 759 women referred for same-day evaluation of suspicious breast lesions between November 2011–March 2013 were included. Diagnostic accuracy was assessed by linking all patients to the national pathology database to identify diagnostic discrepancies, in which case slides were reviewed. Patients'' anxiety was measured in 127 patients by the State Trait and Anxiety Inventory on six moments during the diagnostic workup and changes over time (< = 1 week) were analyzed by mixed effect models.Results
Core-needle biopsy was indicated in 374/759 patients (49.3%) and in 205/759 (27%) patients, invasive or in situ cancer was found. Final diagnosis on the same day was provided for 606/759 (79.8%) patients. Overall, 3/759 (0.4%) discordant findings were identified. Anxiety levels decreased significantly over time from 45.2 to 30.0 (P = <0.001). Anxiety levels decreased from 44.4 to 25.9 (P = <0.001) for patients with benign disease, and remained unchanged for patients diagnosed with malignancies (48.6 to 46.7, P = 0.933). Time trends in anxiety were not affected by other patient or disease characteristics like age, education level or (family) history of breast cancer.Conclusion
Same-day histological diagnosis is feasible in the vast majority of patients, without impairing diagnostic accuracy. Patients'' anxiety rapidly decreased in patients with a benign diagnosis and remained constant in patients with malignancy. 相似文献152.
J Gagnaire O Dauwalder S Boisset D Khau AM Freydière F Ader M Bes G Lina A Tristan ME Reverdy A Marchand T Geissmann Y Benito G Durand JP Charrier J Etienne M Welker A Van Belkum F Vandenesch 《PloS one》2012,7(7):e40660
The aim of the present study was to detect the Staphylococcus aureus delta-toxin using Whole-Cell (WC) Matrix Assisted Laser Desorption Ionization-Time-of-Flight (MALDI-TOF) mass spectrometry (MS), correlate delta-toxin expression with accessory gene regulator (agr) status, and assess the prevalence of agr deficiency in clinical isolates with and without resistance to methicillin and glycopeptides. The position of the delta-toxin peak in the mass spectrum was identified using purified delta-toxin and isogenic wild type and mutant strains for agr-rnaIII, which encodes delta-toxin. Correlation between delta-toxin production and agr RNAIII expression was assessed by northern blotting. A series of 168 consecutive clinical isolates and 23 unrelated glycopeptide-intermediate S. aureus strains (GISA/heterogeneous GISA) were then tested by WC-MALDI-TOF MS. The delta-toxin peak was detected at 3005±5 Thomson, as expected for the naturally formylated delta toxin, or at 3035±5 Thomson for its G10S variant. Multivariate analysis showed that chronicity of S. aureus infection and glycopeptide resistance were significantly associated with delta-toxin deficiency (p?=?0.048; CI 95%: 1.01-10.24; p?=?0.023; CI 95%: 1.20-12.76, respectively). In conclusion, the S. aureus delta-toxin was identified in the WC-MALDI-TOF MS spectrum generated during routine identification procedures. Consequently, agr status can potentially predict infectious complications and rationalise application of novel virulence factor-based therapies. 相似文献
153.
Slimane TA Lenoir C Bello V Delaunay JL Goding JW Chwetzoff S Maurice M Fransen JA Trugnan G 《Experimental cell research》2001,270(1):45-55
We investigated the signals involved in the apical targeting of dipeptidyl peptidase IV (DPP IV/CD26), an archetypal type II transmembrane glycoprotein. A secretory construct, corresponding to the DPP IV ectodomain, was first stably expressed in both the enterocytic-like cell line Caco-2 and the epithelial kidney MDCK cells. Most of the secretory form of the protein was delivered apically in MDCK cells, whereas secretion was 60% basolateral in Caco-2 cells, indicating that DPP IV ectodomain targeting is cell-type-dependent. A chimera (CTM-GFP) containing only the cytoplasmic and transmembrane domains of mouse DPP IV plus the green fluorescent protein was then studied. In both cell lines, this chimera was preferentially expressed at the apical membrane. By contrast, a secretory form of GFP was randomly secreted, indicating that GFP by itself does not contain cryptic targeting information. Comparison of the sequence of the transmembrane domain of DPP IV and several other apically targeted proteins does not show any consensus, suggesting that the apical targeting signal may be conformational. Neither the DPP IV nor the CTM-GFP chimera was enriched in lipid rafts. Together these results indicate that, besides the well-known raft-dependent apical targeting pathway, the fate of the CTM domain of DPP IV may reveal a new raft-independent apical pathway. 相似文献
154.
155.
Feliu C Spakulová M Casanova JC Renaud F Morand S Hugot JP Santalla F Durand P 《The Journal of parasitology》2000,86(3):442-449
Genetic and morphological variability of whipworms Trichuris Roederer, 1761 (Nematoda: Trichuridae), parasites of small rodents in southwestern Europe, was studied. Isozyme patterns of natural populations of nematodes parasitizing rodent species of the Muridae (Apodemus sylvaticus, Apodemus flavicollis, Mus musculus) and Arvicolidae (Clethrionomys glareolus, Microtus agrestis, Microtus arvalis) were analyzed at 6 putative loci. Two diagnostic loci were found in T. muris from Muridae and from Arvicolidae. Thus, the existence of 2 species of Trichuris restricted to different host families was indicated. They included Trichuris muris Schrank, 1788, originally described as being from mice, and Trichuris arvicolae n. sp., parasitizing the above species of Arvicolidae. The morphological variability of both species was compared. Although ranges of all morphological characters of the new species overlapped with those of T. muris, stepwise discriminant analysis yielded a 100% accurate classification of females when using vagina length and egg size. Males of T. muris and T. arvicolae cannot be separated entirely. A set of 6 variables yielded 95.7% discrimination; the most discriminating variables were spicule size and body width. 相似文献
156.
The interaction of ethidium bromide (EB), a DNA intercalator, with two intramolecular triplexes 5'd(G4A4G4-[T4]-C4T4C4-[T4]-G4T4G4), 5'd(G4T4G4-[T4]-G4A4G4-[T4]-C4T4C4) ([T4] represents a stretch of 4 thymine residues) and their precursor duplexes has been investigated by circular dichroism, fluorescence and UV absorption spectroscopy. Binding of EB induces a circular dichroism band in the region around 310 nm which is positive for the duplex forms but negative for the triplex forms. We observed that the binding of EB to the duplex form does not induce the formation of the triplex structures. Thermal denaturation experiments demonstrate that EB stabilizes more the parallel triple helix than the antiparallel one. Analysis of the binding process from fluorescence measurements shows that binding constants to the triple helical forms and to the hairpin reference duplex [T4]-G4A4G4-[T4]-C4T4C4) are close. However the binding site size is larger for the triplexes (4-6 base triplets) than for the duplex (2 base pairs). 相似文献
157.
Laurens Pauwels Andrés Ritter Jonas Goossens Astrid Nagels Durand Hongxia Liu Yangnan Gu Jan Geerinck Marta Boter Robin Vanden Bossche Rebecca De Clercq Jelle Van Leene Kris Gevaert Geert De Jaeger Roberto Solano Sophia Stone Roger W. Innes Judy Callis Alain Goossens 《Plant physiology》2015,169(2):1405-1417
158.
Ral Gagnon Maurice Levasseur Andrea M. Weise Juliette Fauchot Peter G. C. Campbell Bryan J. Weissenboeck Anissa Merzouk Michel Gosselin Bernard Vigneault 《Journal of phycology》2005,41(3):489-497
In the St. Lawrence Estuary, annual recurrent blooms of the toxic dinoflagellate Alexandrium tamarense L. Balech are associated with brackish waters. Riverine inputs are suspected to favor bloom development by increasing water column stability and/or by providing growth stimulants such as humic substances (HS). A 17‐day culture experiment was conducted to evaluate the importance of HS as growth factors for A. tamarense. Nonaxenic cultures were exposed to four HS extracts from three different sources: humic and fulvic acids isolated from the Manicouagan River, Quebec, Canada; humic acids from the Suwannee River, Georgia, United States; and a desalted alkaline soil extract. For each extract, four concentrations were tested as supplements to the artificial Keller medium, a nitrate‐rich algal culture medium. Additions of HS from all sources significantly enhanced the overall growth rates relative to the controls. Concentrations of HS, estimated by UV spectrophotometry, remained constant throughout the exponential growth phase, suggesting that the HS were acting mainly as growth promoters during our experiment. Dose–response curves indicated that HS could increase the growth rate of A. tamarense even at low concentrations, such as those encountered in the St. Lawrence Estuary. Our results support the hypothesis that HS from the Manicouagan River plume can stimulate the development of toxic dinoflagellate blooms. 相似文献
159.
Willis FB Burkhardt EJ Walker JE Johnson MA Spears TD 《Journal of strength and conditioning research / National Strength & Conditioning Association》2005,19(2):286-291
The purpose of this study was to compare the effect of an open-stance cycling protocol (OSCP) with the traditional cycling foot position (TCFP) for preferential vastus medialis oblique (VMO) muscle activation, measured by surface electromyography (SEMG), and preferential VMO activation as defined by achieving significantly increased VMO/VL (vastus lateralis muscle) ratio values. Forty subjects of both sexes participated, 18 symptomatic with patellofemoral pain and 22 control subjects; ages ranged from 18 to 60 years (mean = 28.7 +/- 8 years). The OSCP and TCFP were ridden in randomized order while SEMG recordings were taken of the VMO and VL muscles, collecting the mean of peak amplitudes to calculate VMO/VL ratio values. The SEMG readings were taken 4 times per testing session with randomized resistance and a consistent cycling cadence of 85 rpm. The OSCP displayed preferential VMO activation for all subject groups (F = 40.47, p = 0.0001), and this study revealed a protocol that effectively treats patellofemoral pain. 相似文献
160.
Hrebícek M Mrázová L Seyrantepe V Durand S Roslin NM Nosková L Hartmannová H Ivánek R Cízkova A Poupetová H Sikora J Urinovská J Stranecký V Zeman J Lepage P Roquis D Verner A Ausseil J Beesley CE Maire I Poorthuis BJ van de Kamp J van Diggelen OP Wevers RA Hudson TJ Fujiwara TM Majewski J Morgan K Kmoch S Pshezhetsky AV 《American journal of human genetics》2006,79(5):807-819
Mucopolysaccharidosis IIIC (MPS IIIC, or Sanfilippo C syndrome) is a lysosomal storage disorder caused by the inherited deficiency of the lysosomal membrane enzyme acetyl-coenzyme A: alpha -glucosaminide N-acetyltransferase (N-acetyltransferase), which leads to impaired degradation of heparan sulfate. We report the narrowing of the candidate region to a 2.6-cM interval between D8S1051 and D8S1831 and the identification of the transmembrane protein 76 gene (TMEM76), which encodes a 73-kDa protein with predicted multiple transmembrane domains and glycosylation sites, as the gene that causes MPS IIIC when it is mutated. Four nonsense mutations, 3 frameshift mutations due to deletions or a duplication, 6 splice-site mutations, and 14 missense mutations were identified among 30 probands with MPS IIIC. Functional expression of human TMEM76 and the mouse ortholog demonstrates that it is the gene that encodes the lysosomal N-acetyltransferase and suggests that this enzyme belongs to a new structural class of proteins that transport the activated acetyl residues across the cell membrane. 相似文献