25 resultados para KERATOPLASTY, PENETRATING


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Background and Objectives: Selection of suitable treatment for early gastric cancers, such as endoscopic mucosal resection or the major surgical option of resection of the cancer together with a radical lymph node dissection, may be assisted by comparing the growth characteristics of the cancer with selected molecular characteristics. The results could be used to predict those cases that have a higher risk of developing secondary metastases. Methods: A total of 1,196 Japanese patients with early gastric cancers (648 mucosal cancers and 548 submucosal) were included in the selection of two groups: a metastatic group made up 57 cancers with lymph node metastasis (9 mucosal, 48 submucosal), and a nonmetastatic group of 61 cases (6 mucosal, 55 submucosal) without lymph node metastasis. Growth characteristics of the cancers (superficially spreading, penetrating or invasive, lymph node metastasis) were compared with immunohistochemical expression of single-stranded DNA (ssDNA) protein (apoptosis indicator), bcl-2 and p53 (apoptosis-associated), Ki-67 (cell proliferation), and E-cadherin (cell adhesion) proteins. Results: The lesions in the nonmetastatic group had higher levels of apoptosis and lower expression of bcl-2 than in the metastatic group, indicating an inhibitory role for apoptosis in malignant progression. Apoptosis was also higher in the superficial compared with the invasive lesions of both groups. The lesions in the metastatic group had higher p53 expression than that of the nonmetastatic group, whereas apoptosis in the metastatic group was lower than in the nonmetastatic group. An unproved explanation for this finding may be that, although increased, p53 was mutated and ineffective in promoting apoptotic control of metastatic progression. E-cadherin was decreased in the invasive lesions of both groups, indicating a greater ability of these cells to lose adhesion, to invade the submucosa, and to metastasize. Cell proliferation was highest in the superficial lesions of both metastatic and nonmetastatic groups. Conclusions: Early gastric cancers with low levels of apoptosis, increased bcl-2, and high levels of p53 expression are more likely to invade and metastasize. (C) 2003 Wiley-Liss, Inc.

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Complete small subunit ribosomal RNA gene (ssrDNA) and partial (D1-D3) large subunit ribosomal RNA gene (lsrDNA) sequences were used to estimate the phylogeny of the Digenea via maximum parsimony and Bayesian inference. Here we contribute 80 new ssrDNA and 124 new lsrDNA sequences. Fully complementary data sets of the two genes were assembled from newly generated and previously published sequences and comprised 163 digenean taxa representing 77 nominal families and seven aspidogastrean outgroup taxa representing three families. Analyses were conducted on the genes independently as well as combined and separate analyses including only the higher plagiorchiidan taxa were performed using a reduced-taxon alignment including additional characters that could not be otherwise unambiguously aligned. The combined data analyses yielded the most strongly supported results and differences between the two methods of analysis were primarily in their degree of resolution. The Bayesian analysis including all taxa and characters, and incorporating a model of nucleotide substitution (general-time-reversible with among-site rate heterogeneity), was considered the best estimate of the phylogeny and was used to evaluate their classification and evolution. In broad terms, the Digenea forms a dichotomy that is split between a lineage leading to the Brachylaimoidea, Diplostomoidea and Schistosomatoidea (collectively the Diplostomida nomen novum (nom. nov.)) and the remainder of the Digenea (the Plagiorchiida), in which the Bivesiculata nom. nov. and Transversotremata nom. nov. form the two most basal lineages, followed by the Hemiurata. The remainder of the Plagiorchiida forms a large number of independent lineages leading to the crown clade Xiphidiata nom. nov. that comprises the Allocreadioidea, Gorgoderoidea, Microphalloidea and Plagiorchioidea, which are united by the presence of a penetrating stylet in their cercariae. Although a majority of families and to a lesser degree, superfamilies are supported as currently defined, the traditional divisions of the Echinostomida, Plagiorchiida and Strigeida were found to comprise non-natural assemblages. Therefore, the membership of established higher taxa are emended, new taxa erected and a revised, phylogenetically based classification proposed and discussed in light of ontogeny, morphology and taxonomic history. (C) 2003 Australian Society for Parasitology Inc. Published by Elsevier Science Ltd. All rights reserved.

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Two methods were compared for determining the concentration of penetrative biomass during growth of Rhizopus oligosporus on an artificial solid substrate consisting of an inert gel and starch as the sole source of carbon and energy. The first method was based on the use of a hand microtome to make sections of approximately 0.2- to 0.4-mm thickness parallel to the substrate surface and the determination of the glucosamine content in each slice. Use of glucosamine measurements to estimate biomass concentrations was shown to be problematic due to the large variations in glucosamine content with mycelial age. The second method was a novel method based on the use of confocal scanning laser microscopy to estimate the fractional volume occupied by the biomass. Although it is not simple to translate fractional volumes into dry weights of hyphae due to the lack of experimentally determined conversion factors, measurement of the fractional volumes in themselves is useful for characterizing fungal penetration into the substrate. Growth of penetrative biomass in the artificial model substrate showed two forms of growth with an indistinct mass in the region close to the substrate surface and a few hyphae penetrating perpendicularly to the surface in regions further away from the substrate surface. The biomass profiles against depth obtained from the confocal microscopy showed two linear regions on log-linear plots, which are possibly related to different oxygen availability at different depths within the substrate. Confocal microscopy has the potential to be a powerful tool in the investigation of fungal growth mechanisms in solid-state fermentation. (C) 2003 Wiley Periodicals, Inc.

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Although Darwin was not the first to conceive directional selection as a mechanism of phenotypic change, it is his ideas that were received, and that have shaped population biology to this day. A significant change in his theoretical orientation occurred in the mid-1850s. About then he abandoned environmental selection in favor of competitive selection, and adopted relative adaptation with all its consequences as an alternative. These ideas changed his thinking fundamentally and shaped his argument throughout the writing of his great book. It is still these ideas that predominate today. Here I examine Darwin ' s ideas in relation to his principle of divergence, sexual selection, and the nature and origin of species. Finally I suggest that had he not misunderstood the function of sexual communication he might well have understood the nature of species and provided a more penetrating resolution to Herschell ' s mystery of mysteries, with which he opened his book.

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The spermatozoon of Apus apus is typical of non-passerines in many respects. Features shared with palaeognaths and the Galloanserae are the conical acrosome, shorter than the nucleus; the presence of a proximal as well as distal centriole; the elongate midpiece with mitochondria grouped around an elongate distal centriole; and the presence of a fibrous or amorphous sheath around the principal piece of the axoneme. The perforatorium and endonuclear canal are lost in A. apus as in some other non-passerines. All non-passerines differ from palaeognaths in that the latter have a transversely ribbed fibrous sheath whereas in non-passerines it is amorphous, as in Apus, or absent. The absence of an annulus is an apomorphic but homoplastic feature of swift, psittaciform, gruiform and passerine spermatozoa. The long distal centriole, penetrating the entire midpiece, is a remarkably plesiomorphic feature of the swift spermatozoa, known elsewhere only in palaeognaths. The long centriole of Apus, if not a reversal, would be inconsistent with the former placement of the Apodiformes above the Psittaciformes from DNA-DNA hybridization. In contrast to passerines, in A. apus the microtubules in the spermatid are restricted to a transient single row encircling the cell. The form of the spermatozoon fully justifies the exclusion of swifts from the passerine family Hirundinidae.

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Purpose: To review the epidemiology of serious ocular trauma presenting to Cairns Base Hospital, from the far north Queensland health districts. Methods: A retrospective study of cases from January 1995 to November 2002 inclusive. Cases were analysed with respect to demographics, cause and nature of injury, method of transport and time to and type of ophthalmic treatment, and visual outcomes. Results: There were 226 cases identified, including 71 open-globe and 155 closed-globe injuries. The annual rate of injury was 3.7 per 100 000 for open-globe and 11.8 per 100 000 in total. The Aboriginal and Torres Strait Islander population from the far north Queensland districts showed a disproportionate incidence, with 38% of the total number of injuries, despite representing only 12.3% of the population. Assault in the Aboriginal and Torres Strait Islander population resulted in 69.6% of injuries in men and 75.8% of injuries in women. Of all assaults 76.2% were alcohol-related. The majority (71.5%) of injuries in the Caucasian population were due to accidental blunt and sharp trauma. In total, 77.4% of injuries occurred in men, with an average age of 31 years. Of all open and closed injuries in the study, a final visual acuity of 6/12 or better was achieved in 47.8% of eyes and a final visual acuity of 6/60 or less occurred in 17.7% of patients, 20.8% patients were lost to follow up. In total, 14.1% of open injuries required enucleation/evisceration. Conclusions: The incidence of ocular trauma in far north Queensland is equal to other Australian populations. However, there is a disproportionately high incidence in the Aboriginal and Torres Strait Islander population. Alcohol-related assault is a significant cause of visual loss in the Aboriginal and Torres Strait Islander population. Closed-globe injuries are more common than open globe; however, the latter have poorer visual prognosis. Initial visual acuity of all injuries correlated with final visual acuity.

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In inflammatory disorders (e.g. psoriasis), local concentrations of human neutrophil elastase (HNE), also known as polymorphonuclear leukocyte elastase (HLE), possibly overwhelm its natural inhibitors leading to extracellular matrix degradation. Elevated levels of HNE have been reported in a variety of inflammatory disorders, including psoriasis. Peptidic HNE inhibitors have a common hydrophobic sequence (Ala-Ala-Pro-Val). This peptide sequence inhibits HNE competitively; however the stratum corneum presents an effective barrier to the delivery of this tetrapeptide across the skin. The current work investigates the delivery of the modified peptide whereby the tetrapeptide was lipidated to enhance its ability to penetrate the stratum The tetrapeptide Was Coupled to a racaemic mixture of a short chain lipoamino acid (LAA) resulting in two diastereomers of the lipoamino acid-modified tetrapeptide. The penetration of the lipopeptide mixture was assessed across human epidermis in vitro. The percentage of applied dose penetrating to the receptor over 8 h following administration was 2.53% for the D-LAA conjugate and 1.47% for the L-diastereomer, compared to 0% for the peptide. The D-diastereomer appears to be relatively stable but the L-diastereomer appears to degrade releasing possibly the tetrapeptide and peptide fragment(s). Therefore the results clearly indicate that coupling the tetrapeptide to a short chain LAA enhances its delivery across human epidermis.

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Objective. Clinical interest in C-reactive protein (CRP) - a component of the innate immune system - has focused mainly on its worth as an indicator of disease activity. There has been a resurgence of interest in CRP in the Crohn's disease ( CD) literature because several trials of new treatments for active CD have been characterized by both a large proportion of patients with low CRP ( < 10 mg/l) at entry to the trials and by a negative therapeutic outcome. It is therefore of interest to study the clinical characteristics of patients who are thought to have at the same time both active CD and a low CRP. Material and methods. Patients were prospectively recruited as part of the Brisbane IBD clinical and research programme. Subjects were included in the low CRP group only if there were complete datasets for CRP on all occasions of active CD, and CRP was < 10 mg/l. Active disease was defined as CD activity index (CDAI) > 200. The low CRP group was compared with patients in the raised CRP group for a range of clinical variables as well as the major NOD2 variants. Results. There were data sets for 223 CD patients, with a mean disease duration of 12 years. Of these, 22 patients fulfilled the criteria for low CRP. The low CRP group ( group 1) showed significant differences for disease site (p < 0.01) and for BMI (p = 0.006) compared to the raised CRP group ( group 2). Specifically, group 1 had a predominance of pure ileal disease (95% versus 53%) and lack of pure colonic disease (0% versus 24%) compared to group 2, and their BMI was significantly lower (20.3 kg/m(2) versus 25.0 kg/m(2)). Groups 1 and 2 did not differ with respect to Vienna behaviour at diagnosis, smoking, appendicectomy, extra-intestinal manifestations of CD, or NOD2 SNP variants. There was a trend for low CRP patients with previous ileal resection to evolve to a stricturing phenotype. Fat wrapping was noted in 11/13 (85%) of low CRP patients undergoing ileal resections. Conclusions. Patients with CD and a persistently low CRP in the face of active disease were characterized by an almost exclusive ileal disease distribution and a low BMI, compared to those with a raised CRP. These patients had a similar frequency and distribution of NOD2/CARD15 variants. Stricturing ( v inflammatory or penetrating) behaviour may explain some low CRP. Despite the abnormally low BMI, fat wrapping was noted in the majority of low CRP patients undergoing ileal resection.

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Background: The purpose of the study is to identify factors predictive of outcome after open globe injury in 273 patients admitted to the Royal Brisbane Hospital, Queensland, Australia between 1992 and 2003. Methods: Data were collected retrospectively regarding demographic and geographical factors, injury circumstances, initial visual acuity (VA), injury parameters, details of initial and subsequent surgery, final best corrected VA and complications. Multivariate analysis using binary logistic regression was utilized to identify which factors were related to outcome. Results: 83% of patients were male, with a mean age of 38.3 years. The mean duration of follow up was 16.6 months and 58% of patients (135 of 231) achieved an overall improvement in their vision. Forty-one cases (15%) were enucleated, with half of these cases performed primarily. The prognostic factors indicating the likelihood of a VA of counting fingers or worse were poor initial VA, a large laceration > 10 mm and the presence of a relative afferent pupil defect. Rural patients had a significantly worse final VA than city dwellers and had higher rates of endophthalmitis and enucleation. Conclusions: Assessment of prognostic factors at the time of presentation of an open globe injury enables realistic expectations of final visual outcome by the doctor and the patient. In order to improve outcomes in patients from rural areas, access to specialized eye services need to be upgraded.

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Groundwater-dependent riparian biota is known to be sensitive to changes in soil and groundwater salinity in estuarine systems. The groundwater flow and salinity behaviour in a phreatic aquifer adjoining a partially penetrating, tidal. estuary is investigated through two-dimensional numerical experiments for a lateral cross-section, which explore the influence of factors, such as aquifer and soil materials, tidal amptitudes, and regional groundwater hydraulic gradients. The density contrast between estuarine water and the fresh groundwater drives saltwater penetration of the aquifer even in the case of a marked groundwater hydraulic gradient towards the estuary. We show that tidal fluctuations in estuaries can significantly affect the groundwater salinity distribution in adjacent density-stratified phreatic aquifers. This has consequences for the expected distribution of salinity-sensitive biota in the hyporheic zone as well as vegetation and fauna dependent on water in the riparian soil and aquifer. The shape of the dense saltwater wedge propagating into the adjacent groundwater system is also modified by the estuarine tidal signal, although this effect appears to have only minor influence on the maximum distance penetrated into the aquifer (i.e., location of the 'toe' of the wedge). Tide-induced changes to riparian groundwater salinity are advection-driven, as evidenced by the modified time-averaged groundwater flow dynamics. (c) 2006 Elsevier B.V. All rights reserved.