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Same Clone (same + clone)
Selected AbstractsCONCURRENT GASTRIC AND COLONIC LOW-GRADE MUCOSA-ASSOCIATED LYMPHOID TISSUE LYMPHOMATA IN A PATIENT WITHOUT HELICOBACTER PYLORI INFECTIONDIGESTIVE ENDOSCOPY, Issue 1 2003HIROYUKI OKADA Mucosa-associated lymphoid tissue (MALT) lymphomata observed simultaneously in the stomach and colon are rare. We report concurrent gastric and colonic low-grade MALT lymphomata that originated from the same clone in a 58-year-old Japanese man without Helicobacter pylori infection. Endoscopy showed multiple erosive lesions in the gastric body and antrum, and a single flat elevation with an irregular margin in the sigmoid colon. Histopathological findings of both lesions suggested low-grade MALT lymphoma. Lymphoepithelial lesions were evident in the gastric lesions, but not in the colonic lesion. Southern blot analysis of lymphoma cells revealed the same immunoglobulin heavy-chain rearrangement pattern. The chromosomal translocation t(11;18)(q21;q21) was also observed. After six courses of cyclophosphamide, doxorubicin, vincristine and predonisolone, the gastric lesions disappeared endoscopically, while the colonic lesion persisted. A sigmoidectomy was consequently performed. The chromosomal translocation may be related to the pathogenesis of the present MALT lymphoma case without H. pylori infection. It is interesting that the gastric and colonic lesions differed in response to treatment and in their endoscopic and histologic features, despite having the same origin. [source] Urethral ,recurrence' found 14 years after radical cystectomyINTERNATIONAL JOURNAL OF UROLOGY, Issue 7 2004STEVEN SORSCHER Abstract We report a case of transitional cell urethral cancer diagnosed 14 years after radical cystectomy. Traditionally, in the postcystectomy setting, these cancers have been referred to as ,recurrences'. We review the biological models for the oncogenesis of these cancers and propose that they are typically a result of a field cancerization effect, rather than being derived from the same clone responsible for the original urothelial tumor. [source] The effect of within-genet and between-genet competition on sexual reproduction and vegetative spread in Potentilla anserina ssp. egediiJOURNAL OF ECOLOGY, Issue 3 2004PIRJO RAUTIAINEN Summary 1Patterns of biomass allocation to sexual and vegetative reproduction were examined in a perennial stoloniferous clonal plant, Potentilla anserina (L.) Rydb. ssp. egedii (Wormsk.) Hiitonen, in relation to intraspecific competition between monoclonal and multiclonal ramets. 2We predicted that a lack of competition would generate allocation to rapid, short-distance spread (vegetative propagation), while the presence of competition would increase allocation to long-distance dispersal (sexual reproduction), and that the allocation shift would be more pronounced where the competing ramets were related. 3P. anserina ramets were grown in a glasshouse in small pots, either alone (no competition) or with a size-matched ramet that originated from the same clone (within-genet competition) or a different one (between-genet competition). 4Competition suppressed both growth and reproduction, but there was no treatment response in relative investment at the level of a whole genet, although both mother ramets and their daughters showed clear effects when analysed separately. 5When experiencing competition, the mother ramet allocated relatively more to flowers, whereas allocation to vegetative growth was more intense when competition was absent. Allocation patterns were independent of the relatedness of competitors. 6The results imply that P. anserina can modify the allocation of resources to different life-history traits according to competitive stress. Such flexibility is likely to reflect a shift in the optimal allocation strategy during the life cycle of a plant with a guerilla growth form with rapid exploitation of free space in a new patch by vegetative spread favoured. When spread becomes limited by competition, long-distance dispersal in space (seeds) or time (persistence) becomes beneficial. [source] Clonal composition of the peach-potato aphid Myzus persicae (Homoptera: Aphididae) in France and Scotland: Comparative analysis with IGS fingerprinting and microsatellite markersANNALS OF APPLIED BIOLOGY, Issue 3 2003B FENTON Summary Fourteen colonies of the peach-potato aphid, Myzus persicae, were taken either from French peach trees or weeds in 2001. Thirty five apomictic parthenogenetic lineages (APLs) were established. Ribosomal DNA intergenic spacer (IGS) fingerprinting was used to characterise these and 28 fingerprints were duly obtained. Those lineages with different fingerprints were considered different genotypes and those with the same fingerprint as the same. The genetic identity of APLs was further tested using four microsatellite loci. APLs that differed by IGS fingerprint had distinct microsatellite allele combinations and those that had the same IGS fingerprint had the same microsatellite allele combinations. The results confirmed that IGS types corresponded to different aphid genotypes. Independent APLs with identical IGS and microsatellite genotype were therefore considered different representatives of the same clone. APLs from M. persicae found on Scottish crops in 1995, 1996 and 2001, as well as a long-term laboratory line were also examined by the same methods. Their IGS fingerprints were similar or identical suggesting that they all belonged to the same clone. Microsatellite markers also suggested that these lineages were derived from a single clone. Some field lineages exhibited slight modifications to their IGS fingerprints confirming that the IGS evolves more rapidly than these microsatellite alleles. Thus, IGS will continue to provide a useful marker for aphid fieldwork. [source] Intraclonal variation in RNA viruses: generation, maintenance and consequencesBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2003SANTIAGO F. ELENA This paper explores the evolutionary implications of the enormous variability that characterizes populations of RNA viruses and retroviruses. It begins by examining the magnitude of genetic variation in both natural and experimental populations. In natural populations, differences arise even within individual infected patients, with the per-site nucleotide diversity at this level ranging from < 1% to 6%. In laboratory populations, two viruses sampled from the same clone differed by ,0.7% in their fitness. Three different mechanisms that may be important in maintaining viral genetic variability were tested: (1) Fisher's fundamental theorem, to compare the observed rate of fitness change with the extent of fitness-related variation within the same experimental populations; (2) magnitude of genomic mutation rate, to assess whether it correlated with fitness-related variation, as predicted by the mutation-selection balance hypothesis; (3) frequency-dependent selection, which affords rare genotypes an advantage. The paper concludes with a discussion of two evolutionary consequences of variability: the fixation of deleterious mutations by drift in small populations and the role of clonal interference in large ones. © 2003 The Linnean Society of London. Biological Journal of the Linnean Society, 2003, 79, 17,26. [source] High levels of oestrogen receptor-, in tumorigenesis: inhibition of cell growth and angiogenic factorsCELL PROLIFERATION, Issue 4 2001S. H. Ali We previously found that the stable overexpression of oestrogen receptor-, in the human endothelial cell line ECV304, inhibits its growth in vitro, and that this inhibition is possibly mediated through a down-regulation of the vasoactive agents endothelin-1 and vascular endothelial growth factor. Here we show an in vivo growth-inhibitory effect of oestrogen receptor-, overexpression in tumours initiated in nude mice from the same clone of ECV304. In addition, we show that this growth inhibition is accompanied by an ,v,3 -mediated inhibition of cell migration in vitro, and a down-regulation of the integrin ,v,3, vascular endothelial growth factor and vascularization in vivo. The levels of vascular endothelial growth factor and integrin ,v,3, through their effect on cell growth and migration, contribute to the process of angiogenesis and to the pathogenesis of atherosclerosis and cancer. The results shown here demonstrate that a higher level of oestrogen receptor-, in the cell, through its effect on certain angiogenic factors, may play a role in the control of angiogenesis. [source] Detection of oral streptococci with collagen-binding properties in saliva specimens from mothers and their childrenINTERNATIONAL JOURNAL OF PAEDIATRIC DENTISTRY, Issue 4 2010RYOTA NOMURA International Journal of Paediatric Dentistry 2010; 20: 254,260 Background., Approximately 10,20% of Streptococcus mutans strains have been reported to possess collagen-binding properties, whereas other species in the oral cavity with those properties remain to be elucidated. Aim., To identify strains with collagen-binding properties and analyse their characteristics in comparison with S. mutans. Design., A total of 110 expectorated saliva specimens were collected from 55 pairs of mothers and their children. Bacterial strains with collagen-binding properties were isolated and the species specified. In addition, strains with collagen-binding properties isolated from mother,child pairs were analysed using molecular biological approaches. Results., The detection frequency of strains with collagen-binding properties was shown to be 40.9%, among which S. salivarius was the most frequently detected, followed by S. mutans. The collagen-binding activity of the S. mutans group was the highest, followed by S. salivarius. In addition, S. mutans and S. salivarius strains from 3 and 1 mother,child pairs, respectively, were shown to be the same clones. Conclusions., Our results indicate that S. mutans and S. salivarius are major species with collagen-binding properties in the oral cavity, and that strains with such properties may be related to mother,child transmission. [source] Molecular fingerprinting evidence of the contribution of wildlife vectors in the maintenance of Salmonella Enteritidis infection in layer farmsJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2003E. Liebana Abstract Aims: To provide molecular fingerprinting evidence of the contribution of wildlife vectors in the on-farm epidemiology of Salmonella Enteritidis infections. Methods and Results:Salmonella Enteritidis strains were isolated from wildlife and from farm environment samples collected in 10 egg layer farms. Isolates were typed using plasmid profiling, XbaI-pulsed field gel electrophoresis and PstI,SphI ribotyping. In all 10 farms we were able to identify the same S. Enteritidis clones in wildlife vectors and farm environment. On several occasions the same clones were found before and after cleansing and disinfecting the farm premises. Also in some instances the same clones were present in mice samples, egg contents and spent hens. Conclusions: Definitive molecular evidence for the involvement of several wildlife species (mice, rats, flies, litter beetles and foxes) in the maintenance of S. Enteritidis infection on farms has been presented. Failures in biosecurity seriously compromise the control of this pathogen on laying farms. Significance and Impact of the Study: This paper reports on the use of molecular tools for the study of the epidemiology of S. Enteritidis. It gives useful information to be considered in control programmes for this organism on poultry farms. [source] | |||||||||||||