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Morphological Groups (morphological + groups)
Selected AbstractsGastric inflammatory markers and interleukins in patients with functional dyspepsia, with and without Helicobacter pylori infectionFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 2 2005Leif P. Andersen Abstract Helicobacter pylori is the most important cause of gastritis, peptic ulcers and the development of gastric cancer. The chronic active inflammation is dominated by neutrophils, macrophages, lymphocytes and plasma cells. Several interleukins (IL-8, IL-10 and IFN-,) are involved in the inflammatory process in the gastric mucosa. The aim of this study was to investigate the gastric inflammation in patients with functional dyspepsia. Fifty-three consecutive patients were included and antral biopsies were obtained for histology, culture and immunohistochemistry. The sections were examined for the interleukins IL-4, IL-6, IL-8, IL-10 and IFN-, as well as for the cell markers CD4, CD8, CD14, Cd19, CD25 and CD30. Only CD4 and CD19 were significantly increased in patients with increased gastric inflammation and increased density of H. pylori. However, several of the examined markers (IFN-,, IL-8, IL-10 and CD14) showed a non-significant trend to be increased in patients with extensive gastric inflammation and high density of H. pylori. Therefore, an arbitrary index (IM11) for all the 11 immunological markers was made as an average value for each of the four morphological groups. For the four morphologically different groups of patients the values were 0.49, 0.77, 0.86 and 1.25, respectively. Significant increases in the index from none to moderate antral inflammation as well as the density of H. pylori were found (p < 0.001). By using an index of inflammatory markers trends can be summarized and thereby significant which may be of importance when gastric inflammation is investigated in children and patients with functional dyspepsia. [source] Fungal endophytes in potato roots studied by traditional isolation and cultivation-independent DNA-based methodsFEMS MICROBIOLOGY ECOLOGY, Issue 3 2006Monika Götz Abstract The composition and relative abundance of endophytic fungi in roots of field-grown transgenic T4-lysozyme producing potatoes and the parental line were assessed by classical isolation from root segments and cultivation-independent techniques to test the hypothesis that endophytic fungi are affected by T4-lysozyme. Fungi were isolated from the majority of root segments of both lines and at least 63 morphological groups were obtained with Verticillium dahliae, Cylindrocarpon destructans, Colletotrichum coccodes and Plectosporium tabacinum as the most frequently isolated species. Dominant bands in the fungal fingerprints obtained by denaturing gradient gel electrophoresis analysis of 18S rRNA gene fragments amplified from total community DNA corresponded to the electrophoretic mobility of the 18S rRNA gene fragments of the three most abundant fungal isolates, V. dahliae, C. destructans and Col. coccodes, but not to P. tabacinum. The assignment of the bands to these isolates was confirmed for V. dahliae and Col. coccodes by sequencing of clones. Verticillium dahliae was the most abundant endophytic fungus in the roots of healthy potato plants. Differences in the relative abundance of endophytic fungi colonizing the roots of T4-lysozyme producing potatoes and the parental line could be detected by both methods. [source] Biogeographical patterns of genetic differentiation in dung beetles of the genus Trypocopris (Coleoptera, Geotrupidae) inferred from mtDNA and AFLP analysesJOURNAL OF BIOGEOGRAPHY, Issue 7 2004Loredana Carisio Abstract Aim, To examine the phylogeography and population structure of three dung beetle species of the genus Trypocopris (Coleoptera, Geotrupidae). We wanted to test whether genetic differences and genealogies among populations were in accordance with morphologically described subspecies and we aimed to establish times of divergence among subspecies to depict the appropriate temporal framework of their phylogeographical differentiation. We also wished to investigate the historical demographic events and the relative influences of gene flow and drift on the distribution of genetic variability of the different populations. Location, Europe (mostly Italy). Methods, We collected adult males from dung pats from 15 Italian localities over the period 2000,2002. For sequence analysis, some dried specimens from Albania, Croatia, Slovakia and Spain were also used. We applied cytochrome oxidase I mitochondrial DNA sequencing and the amplified fragment length polymorphism (AFLP) technique to determine whether phylogeographical patterns within the three species support the proposed hypotheses of subspecies designations, and to detect further structure among populations that might mediate diversification. Results and main conclusions, The results show a high concordance between the distribution of mtDNA variation and the main morphological groups recognized as subspecies, which thus may represent independent evolutionary units. The degree of mitochondrial divergence suggests that speciation events occurred during the Pliocene, while diversification of the main subspecific lineages took place in the Pleistocene, from c. 0.3 to 1.5 Ma. Mitochondrial and nuclear data also reveal that there is phylogeographical structuring among populations within each of the main groups and that both contemporary and historical processes determined this pattern of genetic structure. Geographical populations form monophyletic clades in both phylogenetic and network reconstructions. Despite the high levels of intrapopulational diversity, FST values indicate moderate but significant genetic differentiation among populations, and a Bayesian clustering analysis of the AFLP data clearly separates the geographical populations. Nucleotide and gene diversity estimates reveal interspecific differences in the degree of diversification among populations that may be related to the different ecological requirements of the three species. [source] TAXONOMY AND MOLECULAR PHYLOGENY OF THE RED ALGAL GENUS LENORMANDIA (RHODOMELACEAE, CERAMIALES),JOURNAL OF PHYCOLOGY, Issue 1 2002Louise E. Phillips The genus Lenormandia Sonder is currently composed of nine species from Australia and New Zealand. Some of these are well known, but others are rare and ill defined. Material of all nine species has been examined and found to fall into three discrete morphological groups forming highly supported clades on analysis of 18S rDNA sequences. The first group contains four Australian-endemic species and includes the type species L. spectabilis Sonder. Plants have a cleft apex that is not inrolled, a distinctive rhombic surface areolation pattern caused by a one- to two-layered medulla of interlocking cells, lack pseudopericentral cells, and produce their reproductive structures on the blade surfaces. The type species of the genus Lenormandiopsis, L. latifolia (Harvey et Greville) Papenfuss, was found to belong to this group and is thus returned to Lenormandia where it was originally placed. Species falling into the other two groups are removed to new genera that are being described separately. One extremely rare species of Lenormandia from southwestern Australia is transferred to the delesseriacean genus Phitymophora. [source] Plant species and growth form richness along altitudinal gradients in the southwest Ethiopian highlandsJOURNAL OF VEGETATION SCIENCE, Issue 4 2010Wana Desalegn Abstract Questions: Do growth forms and vascular plant richness follow similar patterns along an altitudinal gradient? What are the driving mechanisms that structure richness patterns at the landscape scale? Location: Southwest Ethiopian highlands. Methods: Floristic and environmental data were collected from 74 plots, each covering 400 m2. The plots were distributed along altitudinal gradients. Boosted regression trees were used to derive the patterns of richness distribution along altitudinal gradients. Results: Total vascular plant richness did not show any strong response to altitude. Contrasting patterns of richness were observed for several growth forms. Woody, graminoid and climber species richness showed a unimodal structure. However, each of these morphological groups had a peak of richness at different altitudes: graminoid species attained maximum importance at a lower elevations, followed by climbers and finally woody species at higher elevations. Fern species richness increased monotonically towards higher altitudes, but herbaceous richness had a dented structure at mid-altitudes. Soil sand fraction, silt, slope and organic matter were found to contribute a considerable amount of the predicted variance of richness for total vascular plants and growth forms. Main Conclusions: Hump-shaped species richness patterns were observed for several growth forms. A mid-altitudinal richness peak was the result of a combination of climate-related water,energy dynamics, species,area relationships and local environmental factors, which have direct effects on plant physiological performance. However, altitude represents the composite gradient of several environmental variables that were interrelated. Thus, considering multiple gradients would provide a better picture of richness and the potential mechanisms responsible for the distribution of biodiversity in high-mountain regions of the tropics. [source] Loss of consumers alters the effects of resident assemblages on the local spread of an introduced macroalgaOIKOS, Issue 2 2009F. Bulleri Despite the great interest for the role played by resident assemblages in regulating biological invasions, few studies have assessed how these can influence the spread of exotic species that have successfully established or have included more than one trophic level. On shallow rocky reefs, we assessed how the effects of different benthic assemblages on the spread of an invasive alga, Caulerpa racemosa, are influenced by alterations in the density and species composition of the resident sea urchin assemblage. In order to simulate herbivore species loss scenarios, assemblages dominated by different morphological groups of algae (i.e. turfs or encrusting corallines) or experimentally cleared plots (i.e. bare rock) were exposed to grazing by different combinations of species (Arbacia lixula and Paracentrotus lividus) and densities (natural, ,50% and ,100% of natural densities) of urchins. Algal turfs and encrusting corallines generally facilitated C. racemosa. Manipulating urchins assemblages did not affect the cover and density of fronds of C. racemosa. In contrast, halving the density of P. lividus favoured the penetration of stolons of C. racemosa, consistently among algal assemblages. Other effects of urchins varied among algal assemblages, indicating interactions between trophic levels. In algal turfs, the total removal of urchins caused a decrease in the penetration of stolons, while it enhanced the length of fronds, indicating a shift in the growth form of this clonal plant and, ultimately, a depression of its spreading ability. In bare or encrusting corallines dominated surfaces, the removal of urchins had positive effects on the penetration of stolons and on the length of fronds of C. racemosa, irrespective of one or two species being manipulated and for the intensity of their removal. Our results show that tradeoffs between negative and positive effects of herbivores, varying according to relative densities of species and to the direction and strength of the effects of resident plant assemblages, can influence local rates of spread of C. racemosa. Thus, not only facilitation of exotics by natives can be key in enhancing the spread of exotic species, but it can occur between organisms at different trophic levels. Finally, our findings have important implications for the management of C. racemosa, in view of the progressive domination of shallow rocky reefs by algal turfs. [source] Objective predictors of subjective visual function for different age-related cataract morphologiesOPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 6 2002N. Hakim-Banan Purpose:, To find objective chart tests that give a measure of visual function in the different age-related cataract morphological groups and can be applied in a clinical setting. Methods:, Subjects with age-related cataract (N = 33) were recruited to the study from both private optometric practice and a hospital eye department. All subjects underwent LOCS III grading of their cataract and had their functional vision assessed using the VF-14 questionnaire. High (96%) and low (16%) contrast logMAR visual acuity were measured together with Pelli,Robson contrast sensitivity. A stepwise linear regression was then performed on the data to find significant predictors for VF-14 in the three age-related cataract morphological groups as well as in a mixed group. Results:, Low contrast logMAR visual acuity was a significant predictor of VF-14 in the cortical (p = 0.014) and nuclear (p = 0.024) subgroups. For the mixed morphological group both high and low contrast visual acuity were significant predictors (p < 0.03). There were only three subjects with pure posterior subcapsular cataract and so no meaningful analysis could be performed. Conclusions:, Low contrast logMAR visual acuity may be a better predictor of visual function in cortical and nuclear cataract compared with high contrast logMAR visual acuity or Pelli,Robson contrast sensitivity. [source] Mixed stream channel morphologies: implications for fish community diversityAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 2 2009Christina M. Cianfrani Abstract 1.Stream classification systems are widely used in stream management and restoration. Whereas the principal morphological types of these classification systems are increasingly recognized for their ecological connections, the roles of intermediate and mixed morphologies are still poorly understood, yet may be biologically significant. 2.Twenty-five stream reaches in north-western Vermont were classified by channel morphology to determine whether fish community diversity differed among pool-riffle, mixed (i.e. pool-riffle/cascade, pool-riffle/other) and forced pool-riffle stream morphological groups. Stream reach surveys included cross-sectional surveys, longitudinal profiles, bed substrate characterization, and fish surveys. 3.Three fish community diversity measures were calculated: (1) species richness (S); (2) Shannon,Weaver Index (H,); and (3) Simpson's Index (1/D). Multivariate analysis of covariance (MANCOVA) followed by analysis of variance (ANOVA) were used to explore potential differences in fish diversity among stream morphological groups. Fish diversity was significantly different for all three community diversity measures (P,0.05), with pool-riffle/cascade morphology consistently exhibiting the greatest fish diversity and forced pool-riffle the lowest. 4.These results suggest that fish community diversity is significantly associated with distinct channel morphologies. Generally, pool-riffle/cascade and pool-riffle/other stream morphological groups supported habitats that fostered greater species diversity than more homogeneous and uniform pool-riffle reaches. The observed patterns of diversity are likely to be the result of habitat patches created by variations in flow and other physical characteristics in reaches of mixed morphologies. 5.These results support fish sampling schemes that incorporate morphological heterogeneity, such as proportional-distance designation. Sampling strategies that focus on homogeneous reaches may underestimate diversity, and misrepresent stream condition when fish community data are used in indices of biological integrity (IBIs). Reaches of mixed stream morphologies should be recognized as areas of biological importance in stream and catchment management and in conservation efforts. Copyright © 2008 John Wiley & Sons, Ltd. [source] | |||||||||||||