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New Patch (new + patch)
Selected AbstractsThe development of cutaneous lesions during follow-up of patients with primary neuritic leprosyINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 3 2005Sujai Suneetha PhD Background, Primary neuritic leprosy (PNL) is a rare form of leprosy where the characteristic skin lesions are absent. Investigations of apparently normal skin from the areas of sensory change have revealed microscopic evidence of nerve involvement. Clinical studies have found that a proportion of patients develop visible skin lesions during follow-up. The aim of the study was to perform a clinical and histological analysis of PNL patients who developed visible skin lesions during treatment and follow-up, to gain insight into the pathogenesis of the disease. Methods, Twenty-nine individuals in a series of 182 PNL patients developed visible skin lesions during follow-up. Analysis of the number, location, histology and time of onset of the new skin lesions in relation to the type and regularity of the treatment regimen were noted. A biopsy from the new skin lesion when available was compared with the nerve biopsy findings at the time of initial diagnosis. Results, Thirty-eight per cent of patients developed a single patch and 28% developed two patches. Over three-quarters of these were on the lower limb (47%) or the upper limb (29%). Sixty-two per cent of patients developed the lesions within 2 years of the onset of symptoms. Patients on regular treatment developed patches earlier than those on irregular treatment or no treatment. A skin biopsy from the new patch revealed borderline tuberculoid leprosy histology in 47% of the patients. Conclusions, The findings suggest that leprosy primarily affects the nerve and that a neuritic phase precedes the development of visible cutaneous lesions. [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] Comparative population genetic structures of the fruit fly Urophora cardui and its primary parasitoid Eurytoma robustaENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 3 2003Jes Johannesen Abstract The interaction between two species may depend on geographic scale and this in turn can affect co-evolution among them. The present study comparatively examines population genetic structures of the tephritid gall fly Urophora cardui and its primary ectoparasitoid Eurytoma robusta for inference of relative dispersal patterns and host-parasitoid specificity. Genetic differentiation patterns indicated two levels of hierarchical structure in both species: locally similar distance-dependencies but globally differences. Locally, both species showed isolation by distance and a high correlation between host and parasitoid FST for the same population-pairs was found. At the local level, E. robusta populations were most structured. These findings suggest that locally E. robusta is tracking behind its host, U. cardui, and that colonisation of new patches by both species underlie a stepping-stone dispersal process. The investigation as a whole showed that U. cardui populations were hierarchically structured across a genetic-geographical cline. There was no sign of a comparable cline in E. robusta where populations globally became independent of one another and of the host. The different degree of hierarchical genetic structure of the two species suggests that dispersal processes or interactions differ relative to geographical scale and population history. [source] Modelling habitat selection of Common Cranes Grus grus wintering in Portugal using multiple logistic regressionIBIS, Issue 3 2000ALDINA M.A. FRANCO Predictive models of habitat suitability for the Common Crane Grus grus in a wintering area of southern Portugal were derived using logistic multiple regression and Geographic Information Systems. The study area was characterized by landscape variables and surveyed uniformly for the presence of cranes. The most important variables were distance to roosts, to open Holm Oak woods and to villages, and the occurrence of unpaved roads, shrubby vegetation, slope and orchards. Two models were built, the second having one variable fewer than the first. The selection of the best model was based on statistical and biological criteria. Crane distribution was negatively related to: distance to open Holm Oak Quercus rotundifolia woods and roosts. Additionally, unsuitable vegetation and orchard areas are avoided. In these areas movement is difficult, food availability is reduced and the risk of predation increased. We also found that villages and roads were avoided; disturbance is a significant factor for this species. Some management guidelines are proposed for the area: (1) maintenance of open Holm Oak woodlands, (2) incentives to avoid the abandonment of traditional agriculture and pastoral use of the area, which would lead to an increase of shrubby vegetation areas, (3) preservation of suitable roosting places and (4) management of new patches of forest and orchards. [source] | ||||||||||