421 research outputs found

    Optical coherence tomography for patch test grading: A prospective study on its use for noninvasive diagnosis of allergic contact dermatitis

    Get PDF
    Background: The diagnosis of allergic contact dermatitis should be confirmed by skin patch tests. Distinguishing between irritant and allergic reactions is sometimes difficult. Objectives: To analyse the in vivo morphological changes in patch test reactions compared to healthy skin, and to detect subclinical changes in doubtful reactions using optical coherence tomography (OCT). To develop an OCT-based algorithm to support patch-test grading. Methods: One hundred twenty-nine skin patch-test areas were scanned with OCT to evaluate the following features: architectural and vascular morphology, epidermal thickness, optical attenuation coefficient (AC), and blood flow at 0.1, 0.2, and 0.35 mm depth. Results: Most common OCT features of acute contact allergic reactions in patch tests were spongiosis with microvesicles (94.8%), macrovesicles (60.3%), and coalescing vesicles (46.6%), the latter useful in differentiating acute allergic from irritant dermatitis (P-value <.05). Objective quantitative parameters correlated well with the severity grade: epidermal thickness due to spongiosis, AC (P-value <.05) and blood flow at 0.2 and 0.35 mm (P-value <.01). Conclusions: OCT as a noninvasive diagnostic tool, established for skin cancer diagnosis, is useful for evaluating contact allergic patch-test reactions. Not only morphological but also objective features such as blood flow and AC correlate with the reaction severity. Further studies are needed to explore the differences in irritant and allergic contact dermatitis

    Deep subcutaneous application of poly-L-lactic acid as a filler for facial lipoatrophy in HIV-infected patients

    Get PDF
    Introduction: Facial lipoatrophy is a crucial problem of HIV-infected patients undergoing highly active antiretroviral therapy (HAART). Poly-L-lactic acid (PLA), provided as New-Fill(R)/Sculptra(TM), is known as one possible treatment option. In 2004 PLA was approved by the FDA as Sculptra(TM) for the treatment of lipoatrophy of the face in HIV-infected patients. While the first trials demonstrated relevant efficacy, this was to some extent linked to unwanted effects. As the depth of injection was considered relevant in this context, the application modalities of the preparation were changed. The preparation was to be injected more deeply into subcutaneous tissue, after increased dilution. Material and Methods: To test this approach we performed a pilot study following the new recommendations in 14 patients. Results: While the efficacy turned out to be about the same, tolerability was markedly improved. The increase in facial dermal thickness was particularly obvious in those patients who had suffered from lipoatrophy for a comparatively small period of time. Conclusion: With the new recommendations to dilute PLA powder and to inject it into the deeper subcutaneous tissue nodule formation is a minor problem. However, good treatment results can only be achieved if lipoatrophy is not too intense; treatment intervals should be about 2 - 3 weeks. Copyright (C) 2005 S. Karger AG, Basel

    Efficacy and safety of medications for antihistamine-refractory chronic spontaneous urticaria: a systematic review and network meta-analysis

    Get PDF
    Purpose Most medications for antihistamine-refractory chronic spontaneous urticaria (CSU) have not been compared head-to-head. This systematic review and network meta-analysis evaluates their relative efficacy and safety. Methods Electronic databases were searched until 05 May 2022 for randomized controlled trials investigating systemic medications for antihistamine-refractory CSU. The change in the urticaria activity score over seven days (UAS7) and occurrence of adverse events were compared between treatments using random-effects network meta-analysis models. Results In all, 32 studies with 3641 patients receiving 31 different systemic medical interventions were included. Among currently available drugs, omalizumab 300 mg injected every 4 weeks and cyclosporine 3–5 mg/kg daily per os were most effective in reducing the UAS7 with a reduction of −10.45 (95% confidence interval [CI]: −12.35, −8.55) and of −10.40 (95% CI: −19.4, −1.4) compared to placebo. Similar efficacies were shown by the nonapproved agents ligelizumab 72 mg injected every 4 weeks (−11.67, 95% CI: −16.80, −7.15) and fenebrutinib 400 mg daily per os (−9.50, 95% CI: −17.56, −1.44). The odds ratio for the occurrence of an adverse event with placebo as comparator was 1.09 for omalizumab (95% CI: 0.83, 1.42), 2.16 for cyclosporine (95% CI: 0.77, 6.07: GRADE; moderate certainty), 0.89 for ligelizumab (95% CI: 0.47, 1.69), and 2.14 for fenebrutinib (95% CI: 0.62, 7.38) in the mentioned dosages. Conclusion Omalizumab 300 mg injected every 4 weeks and cyclosporine 3–5 mg/kg daily per os are the most effective currently available drugs for antihistamine-refractory CSU. Cyclosporine shows a relatively less favorable safety profile

    Clinical pharmacology becomes a specialty in South Africa

    Get PDF
    South Africa recently became the first African country where clinical pharmacology has been approved as a specialty. This article outlines the need for clinical pharmacologists, their role in advancing public health, the potential benefits to the country, and recommendations for ensuring a healthy future for the discipline.http://www.samj.org.zaam2014ay201

    Effects of habitat and land use on breeding season density of male Asian Houbara Chlamydotis macqueenii

    Get PDF
    Landscape-scale habitat and land-use influences on Asian Houbara Chlamydotis macqueenii (IUCN Vulnerable) remain unstudied, while estimating numbers of this cryptic, low-density, over-hunted species is challenging. In spring 2013, male houbara were recorded at 231 point counts, conducted twice, across a gradient of sheep density and shrub assemblages within 14,300 km² of the Kyzylkum Desert, Uzbekistan. Four sets of models related male abundance to: (1) vegetation structure (shrub height and substrate); (2) shrub assemblage; (3) shrub species composition (multidimensional scaling); (4) remote-sensed derived land-cover (GLOBCOVER, 4 variables). Each set also incorporated measures of landscape rugosity and sheep density. For each set, multi-model inference was applied to generalised linear mixed models of visit-specific counts that included important detectability covariates and point ID as a random effect. Vegetation structure received strongest support, followed by shrub species composition and shrub assemblage, with weakest support for the GLOBCOVER model set. Male houbara numbers were greater with lower mean shrub height, more gravel and flatter surfaces, but were unaffected by sheep density. Male density (mean 0.14 km-2, 95% CI, 0.12‒0.15) estimated by distance analysis differed substantially among shrub assemblages, being highest in vegetation dominated by Salsola rigida (0.22 [CI, 0.20‒0.25]), high in areas of S. arbuscula and Astragalus (0.14 [CI, 0.13‒0.16] and 0.15 [CI, 0.14‒0.17] respectively), lower (0.09 [CI, 0.08‒0.10]) in Artemisia and lowest (0.04 [CI, 0.04‒0.05]) in Calligonum. The study area was estimated to hold 1,824 males (CI: 1,645‒2,030). The spatial distribution of relative male houbara abundance, predicted from vegetation structure models, had the strongest correspondence with observed numbers in both model-calibration and the subsequent year’s data. We found no effect of pastoralism on male distribution but potential effects on nesting females are unknown. Density differences among shrub communities suggest extrapolation to estimate country- or range-wide population size must take account of vegetation composition

    Seasonal shifts in foraging distribution due to individual flexibility in a tropical pelagic forager, the Ascension frigatebird

    Get PDF
    This is the final version of the article. Available from Inter Research via the DOI in this record.Predators exploiting tropical pelagic waters characterised by low fluctuations in seasonal temperature and salinity may require different foraging strategies than predators that can rely on persistently productive marine features. Consistent individual differences in foraging strategies have been found in temperate seabirds, but it is unclear whether such foraging special-isation would be beneficial in unpredictable tropical pelagic waters. We examined whether foraging trip characteristics of a tropical seabird were consistent between seasons and within individuals and explored whether seasonal changes could be explained by environmental variables. Ascension frigatebird Fregata aquila trips lasted up to 18 d and covered a total travel distance of up to 7047 km, but adult frigatebirds stayed within a radius of 1150 km of Ascension Island. We found that the 50% utilisation distribution of the population expanded southwestward in the cool season due to individuals performing more and longer trips in a southerly and westerly direction during the cool compared to the hot season. Individual repeatability was low (R < 0.25) for all trip characteristics, and we were unable to explain seasonal changes in time spent at sea using oceanographic or atmospheric variables. Instead, frigatebird usage per area was almost exclusively determined by distance from the colony, and although individuals spent more time in distant portions of their foraging trips, the amount of time spent per unit area decreased exponentially with increasing distance from the colony. This study indicates that, in a relatively featureless environment, high individual consistency may not be a beneficial trait for pelagic predators.The work on Ascension Island was partly funded by a Darwin Grant (# 19026) to Ascension Island Government and the University of Exeter (A.B. and B.G.), managed on-island by N.W. and S.W. Nigel Butcher and Andrew Asque assisted with preparation of loggers and equipment, and Elizabeth Marsden kindly provided the base station to download data

    Stable isotope analysis provides new information on winter habitat use of declining avian migrants that is relevant to their conservation

    Get PDF
    Winter habitat use and the magnitude of migratory connectivity are important parameters when assessing drivers of the marked declines in avian migrants. Such information is unavailable for most species. We use a stable isotope approach to assess these factors for three declining African-Eurasian migrants whose winter ecology is poorly known: wood warbler Phylloscopus sibilatrix, house martin Delichon urbicum and common swift Apus apus. Spatially segregated breeding wood warbler populations (sampled across a 800 km transect), house martins and common swifts (sampled across a 3,500 km transect) exhibited statistically identical intra-specific carbon and nitrogen isotope ratios in winter grown feathers. Such patterns are compatible with a high degree of migratory connectivity, but could arise if species use isotopically similar resources at different locations. Wood warbler carbon isotope ratios are more depleted than typical for African-Eurasian migrants and are compatible with use of moist lowland forest. The very limited variance in these ratios indicates specialisation on isotopically restricted resources, which may drive the similarity in wood warbler populations' stable isotope ratios and increase susceptibility to environmental change within its wintering grounds. House martins were previously considered to primarily use moist montane forest during the winter, but this seems unlikely given the enriched nature of their carbon isotope ratios. House martins use a narrower isotopic range of resources than the common swift, indicative of increased specialisation or a relatively limited wintering range; both factors could increase house martins' vulnerability to environmental change. The marked variance in isotope ratios within each common swift population contributes to the lack of population specific signatures and indicates that the species is less vulnerable to environmental change in sub-Saharan Africa than our other focal species. Our findings demonstrate how stable isotope research can contribute to understanding avian migrants' winter ecology and conservation status
    corecore