2,852 research outputs found

    Experimental antibiotic treatment identifies potential pathogens of white band disease in the endangered Caribbean coral Acropora cervicornis

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    Coral diseases have been increasingly reported over the past few decades and are a major contributor to coral decline worldwide. The Caribbean, in particular, has been noted as a hotspot for coral disease, and the aptly named white syndromes have caused the decline of the dominant reef building corals throughout their range. White band disease (WBD) has been implicated in the dramatic loss of Acropora cervicornis and Acropora palmata since the 1970s, resulting in both species being listed as critically endangered on the International Union for Conservation of Nature Red list. The causal agent of WBD remains unknown, although recent studies based on challenge experiments with filtrate from infected hosts concluded that the disease is probably caused by bacteria. Here, we report an experiment using four different antibiotic treatments, targeting different members of the disease-associated microbial community. Two antibiotics, ampicillin and paromomycin, arrested the disease completely, and by comparing with community shifts brought about by treatments that did not arrest the disease, we have identified the likely candidate causal agent or agents of WBD. Our interpretation of the experimental treatments is that one or a combination of up to three specific bacterial types, detected consistently in diseased corals but not detectable in healthy corals, are likely causal agents of WBD. In addition, a histophagous ciliate (Philaster lucinda) identical to that found consistently in association with white syndrome in Indo-Pacific acroporas was also consistently detected in allWBDsamples and absent in healthy coral. Treatment with metronidazole reduced it to below detection limits, but did not arrest the disease. However, the microscopic disease signs changed, suggesting a secondary role in disease causation for this ciliate. In future studies to identify a causal agent ofWBDvia tests of Henle–Koch’s postulates, it will be vital to experimentally control for populations of the other potential pathogens identified in this study

    Formation of Nanometer-Thick Water Layer at High Humidity on Dynamic Crystalline Material Composed of Multi-Interactive Molecules

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    Crystalline powders self-assembled from interactive discrete molecules reversibly transformed from a porous structure to a 2D one with a nanometer-thick H2O layer by hydration/dehydration. Multi-point weak intermolecular interactions contributed to maintenance of each phase. This structure transformation induced a humidity-dependent ion conductivity change from insulator to 3.4 x 10(-3) S cm(-1).open1122sciescopu

    Transarterial embolisation of a large focal nodular hyperplasia, using microspheres, in a paediatric patient

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    Benign liver tumours are uncommon in children, haemangiomas being the most frequent. Focal nodular hyperplasia (FNH) represents about 2% of paediatric liver tumours. In children, as in adults, a conservative approach is generally recommended. However, large lesions (greater than 5 cm) are more frequent in the paediatric age group, and in these cases, as well as in growing lesions, surgical removal may be advised. Transarterial embolisation (TAE) has been a successful alternative option described in older patients, especially in cases where surgical removal is not possible. This minimally invasive procedure may also become an option in the paediatric group. The authors report the case of a boy with a large FNH treated with TAE using microspheres

    Transarterial embolisation of a large focal nodular hyperplasia, using microspheres, in a paediatric patient

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    Benign liver tumours are uncommon in children, haemangiomas being the most frequent. Focal nodular hyperplasia (FNH) represents about 2% of paediatric liver tumours. In children, as in adults, a conservative approach is generally recommended. However, large lesions (greater than 5 cm) are more frequent in the paediatric age group, and in these cases, as well as in growing lesions, surgical removal may be advised. Transarterial embolisation (TAE) has been a successful alternative option described in older patients, especially in cases where surgical removal is not possible. This minimally invasive procedure may also become an option in the paediatric group. The authors report the case of a boy with a large FNH treated with TAE using microspheres

    Dermite de Contacto à Mitomicina C. 6 Casos

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    A Mitomicina C está entre uma variedade de agentes quimioterapêuticos intravesicais actualmente disponíveis para o tratamento do carcinoma superficial da bexiga. Cerca de9% destes doentes desenvolve reacções adversas cutâneas, geralmente dermites de contacto, localizadas nas mãos, pés, genitais, ou erupções mais disseminadas. Descrevem-se 6 casos de dermite de contacto alérgica à Mitomicina C, observados entre Junho/2004 e Março/2005,emcinco doentes do sexo masculino e umdo sexo feminino, com uma idade média de 70 anos

    Co-firing of biomass with coals Part 1. Thermogravimetric kinetic analysis of combustion of fir (abies bornmulleriana) wood

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    The chemical composition and reactivity of fir (Abies bornmulleriana) wood under non-isothermal thermogravimetric (TG) conditions were studied. Oxidation of the wood sample at temperatures near 600 A degrees C caused the loss of aliphatics from the structure of the wood and created a char heavily containing C-O functionalities and of highly aromatic character. On-line FTIR recordings of the combustion of wood indicated the oxidation of carbonaceous and hydrogen content of the wood and release of some hydrocarbons due to pyrolysis reactions that occurred during combustion of the wood. TG analysis was used to study combustion of fir wood. Non-isothermal TG data were used to evaluate the kinetics of the combustion of this carbonaceous material. The article reports application of Ozawa-Flynn-Wall model to deal with non-isothermal TG data for the evaluation of the activation energy corresponding to the combustion of the fir wood. The average activation energy related to fir wood combustion was 128.9 kJ/mol, and the average reaction order for the combustion of wood was calculated as 0.30

    Characterisation of the bacterial and fungal communities associated with different lesion sizes of Dark Spot Syndrome occurring in the Coral Stephanocoenia intersepta

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    The number and prevalence of coral diseases/syndromes are increasing worldwide. Dark Spot Syndrome (DSS) afflicts numerous coral species and is widespread throughout the Caribbean, yet there are no known causal agents. In this study we aimed to characterise the microbial communities (bacteria and fungi) associated with DSS lesions affecting the coral Stephanocoenia intersepta using nonculture molecular techniques. Bacterial diversity of healthy tissues (H), those in advance of the lesion interface (apparently healthy AH), and three sizes of disease lesions (small, medium, and large) varied significantly (ANOSIM R = 0.052 p,0.001), apart from the medium and large lesions, which were similar in their community profile. Four bacteria fitted into the pattern expected from potential pathogens; namely absent from H, increasing in abundance within AH, and dominant in the lesions themselves. These included ribotypes related to Corynebacterium (KC190237), Acinetobacter (KC190251), Parvularculaceae (KC19027), and Oscillatoria (KC190271). Furthermore, two Vibrio species, a genus including many proposed coral pathogens, dominated the disease lesion and were absent from H and AH tissues, making them candidates as potential pathogens for DSS. In contrast, other members of bacteria from the same genus, such as V. harveyii were present throughout all sample types, supporting previous studies where potential coral pathogens exist in healthy tissues. Fungal diversity varied significantly as well, however the main difference between diseased and healthy tissues was the dominance of one ribotype, closely related to the plant pathogen, Rhytisma acerinum, a known causal agent of tar spot on tree leaves. As the corals’ symbiotic algae have been shown to turn to a darker pigmented state in DSS (giving rise to the syndromes name), the two most likely pathogens are R. acerinum and the bacterium Oscillatoria, which has been identified as the causal agent of the colouration in Black Band Disease, another widespread coral disease

    Do female association preferences predict the likelihood of reproduction?

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    Sexual selection acting on male traits through female mate choice is commonly inferred from female association preferences in dichotomous mate choice experiments. However, there are surprisingly few empirical demonstrations that such association preferences predict the likelihood of females reproducing with a particular male. This information is essential to confirm association preferences as good predictors of mate choice. We used green swordtails (<i>Xiphophorus helleri</i>) to test whether association preferences predict the likelihood of a female reproducing with a male. Females were tested for a preference for long- or short-sworded males in a standard dichotomous choice experiment and then allowed free access to either their preferred or non-preferred male. If females subsequently failed to produce fry, they were provided a second unfamiliar male with similar sword length to the first male. Females were more likely to reproduce with preferred than non-preferred males, but for those that reproduced, neither the status (preferred/non-preferred) nor the sword length (long/short) of the male had an effect on brood size or relative investment in growth by the female. There was no overall preference based on sword length in this study, but male sword length did affect likelihood of reproduction, with females more likely to reproduce with long- than short-sworded males (independent of preference for such males in earlier choice tests). These results suggest that female association preferences are good indicators of female mate choice but that ornament characteristics of the male are also important

    Body composition phenotypes in systemic lupus erythematosus and rheumatoid arthritis: a comparative study of caucasian female patients.

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    OBJECTIVES: The amount and distribution of fat and lean mass have important implications for health and systemic inflammation may represent a risk for altered body composition. The aim of this study was to analyse whether changes in body composition are similarly associated with systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA), two inflammatory conditions of different pathogenesis. METHODS: Body mass index (BMI), waist circumference, fat mass (FM) and fat-free mass (FFM) were measured in 92 women with SLE, 89 with RA and 107 controls. Results were compared among the 3 groups and correlations of FM percentage were explored within SLE and RA. RESULTS: Abnormal body composition was more frequent in women with SLE and RA than in non-inflammatory controls, despite having a similar BMI. RA diagnosis was significantly associated with overfat (OR=2.782, 95%CI 1.470-5.264; p=0.002) and central obesity (OR=2.998, 95%CI 1.016-8.841; p=0.04), while sarcopenia was more common among SLE (OR=3.003; 95%CI 1.178-7.676; p=0.01). Sarcopenic obesity, i.e. the coexistence of overfat with sarcopenia, was present in 6.5% of SLE and 5.6% of RA women, but no controls. Independent correlations of FM percentage in women with SLE included smoking, disease activity and CRP. In RA, education, disease activity and cumulative corticosteroid dose were identified as independent predictors of FM percentage. CONCLUSIONS: Women with SLE or RA diagnosis are more likely to have abnormal body composition phenotype, with some differences existing between these two conditions. Changes in body composition are partly explained by the inflammatory burden of disease and its treatment
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