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Potential Presence (potential + presence)
Selected AbstractsLiesegang rings in fine needle aspirate of breast cysts with predominance of apocrine cells: A study of 14 casesDIAGNOSTIC CYTOPATHOLOGY, Issue 10 2008F.I.A.C., Raj K. Gupta M.D. Abstract Fine needle aspirate (FNA) from 14 cases (age range 17,84 years), with Liesegang rings (LR's) in breast cysts seen over a period of 26 years comprised the material of this study from more than 38,000 FNA's of the breast which had been done for a variety of breast lesions. In six of the 14 cases, the aspirate was obtained under ultrasound guidance whereas in the remaining cases it was collected from a palpable lesion. The aspiration was performed using a 22 gauge needle and the syringe and needle contents were washed in a cytology container with 30% ethyl alcohol in physiologic saline. The cytologic preparations from half of the sample were made on a 5 micron Schleicher and Schuell filter and stained by Papanicolaou method whereas from the remainder of the sample a cell block was made and sections cut, stained with hematoxylin-eosin (H&E) and used for immunohistochemical study. Filter preparations and cell blocks revealed cyanophilic, spherical, ring-like structures of various sizes and shape mostly with double walls, and striations with amorphous material in the lumen and under polarized light were nonrefractile. Seen also were several apocrine cells and some macrophages and the LR's were found to be negative on immunostains for EMA and CK, and a panel of other special stains (Table I). Since LR's can be mistaken for ova, larvae, or parasites, it is important to be aware of their potential presence in aspirate samples of breast cysts to avoid a misdiagnosis. The exact mechanism of formation of LR's is not fully understood and certain views as proposed are discussed in this presentation. Diagn. Cytopathol. 2008;36:701,704. © 2008 Wiley-Liss, Inc. [source] Denaturing capillary electrophoresis for automated detection of L858R mutation in exon 21 of the epidermal growth factor receptor gene in prediction of the outcome of lung cancer therapyJOURNAL OF SEPARATION SCIENCE, JSS, Issue 15 2010Lucie Benesova Abstract The presence of activating mutations within the tyrosine kinase domain of the epidermal growth factor receptor gene has been attributed to a positive response to biological therapy of lung cancer by small-molecular tyrosine kinase inhibitors, gefitinib and erlotinib. Among the two most significant mutation types are deletions in exon 19 and a single point substitution in exon 21 (termed L858R). The exon 19 deletions can readily be examined by fragment analysis, due to the characteristic length difference between the normal and mutated PCR product. Analysis of the L858R point mutation, however, presents a greater challenge. The current paper is aimed at developing a sensitive, yet simple, low-cost mutation detection assay directed at the L858R mutation using a method based on CE of heteroduplexes under partial denaturing conditions. We perform optimization of separation conditions on different commercial instruments including ones equipped with 8, 16 and 96 capillaries. We present normalized migration reproducibility in the range from 1 (8 and 16) to 5% (96) RSD. A reliable distinction of the R836R silent polymorphism from a potential presence of the L858R mutation is also demonstrated. In its implementation, the presented assay is just another application running on a conventional CE platform without the need of dedicated instrumentation. [source] Identification and characterization of enterococci from bryndza cheeseLETTERS IN APPLIED MICROBIOLOGY, Issue 6 2006D. Jurkovi Abstract Aims:, To identify enterococci isolated from sheep milk cheese , bryndza, and to compare differences in the composition of enterococcal microflora affected by the season, and to evaluate the potential presence of vancomycin resistance and virulence determinants. Methods and Results:, Bacterial strains were isolated during analysis of bryndza cheese and identified on the genus and species level by phenotypic methods and with commercial biochemical sets. The identification of the species, Enterococcus faecium, Ent. durans and Ent. faecalis, was confirmed by PCR using species-specific primers for ddl genes. PCR was also used for assessment of presence of vanA and vanB genes and virulence determinants gelE, agg and cytolysin genes namely: cylLL, cylLS, cylM, cylB and cylA. Among 308 Enterococcus sp. strains, 177 isolates were proved to be Ent. faecium, 59 to be Ent. durans and 41 to be Ent. faecalis. Vancomycin resistance genes vanA and vanB were not detected. Agar plate testing confirmed their absence. Gene gelE, however, was found in 20 Ent. faecalis isolates, but only 13 of them showed gelatinase-positive phenotype. Seven isolates had five cytolysin genes, but none of the isolates exhibited a positive haemolytic phenotype. Four isolates possessed the agg gene. The prevalence of Ent. faecium species was highest in samples from the winter season harvest. Conclusions:,Ent. faecium is the dominant enterococcal species in bryndza cheese and the most prevalent in the winter season product. None of the Enterococcus sp. strains was proved to have vanA or vanB genes and the vancomycin resistance. Significance and Impact of the Study:, To our knowledge, this is the first report of enterococcal microflora in bryndza cheese and its evaluation for the presence of vanA and vanB genes as well as virulence determinants. [source] Development of a PCR test to detect the downy mildew causal agent Plasmopara halstedii in sunflower seedsPLANT PATHOLOGY, Issue 2 2007R. Ioos Plasmopara halstedii, the causal agent of downy mildew of sunflower, is an obligate parasite but viable sporangia and oospores of the pathogen may be found in a quiescent state in seeds of sunflower and therefore may be transported with sunflower seeds in international commercial exchanges. In order to prevent the spread of this pathogen, especially the introduction of potentially new races, an efficient method to analyse sunflower seed samples is required. In this study, a P. halstedii -specific polymerase chain reaction (PCR) test was developed based on the ribosomal large sub unit (LSU) DNA. The forward (PHAL-F) and reverse (PHAL-R) PCR primers were designed from two polymorphic regions of LSU. After screening 22 isolates of P. halstedii corresponding to different races and countries and 32 other oomycete, deuteromycete and ascomycete isolates, the PHAL-F/R primers amplified only a single PCR band of c. 310 bp from P. halstedii. The PHAL-F/R PCR test could detect as little as 3 pg of P. halstedii genomic DNA per 20 µL reaction volume and enabled the direct detection of P. halstedii in 35 g sunflower seed samples without the need for any prior biological baiting step. An internal amplification control (IAC) was developed to help discriminate against false negative samples due to the potential presence of inhibitory compounds in DNA extracts. The test was successfully used on samples of naturally contaminated seeds. These new molecular tools should be of great interest for quarantine seed testing purposes. [source] | ||||||||||