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41.
James T. Li Mark C. Swanson Roy J. Rando Patricia Wentz-Murtha Inna G. Ovsyannikova Ferran Morell Manuel Lopez Charles E. Reed 《Aerobiologia》1996,12(1):173-176
There have been reported epidemics of severe asthma in Barcelona, Spain, linked to a 10 kDa low molecular mass (LMM) allergen from soybean hulls that became airborne during unloading of ships. As a preliminary probe of the potential for dispersion of this allergen in USA cities, four automated air samplers were placed around a grain elevator in New Orleans and operated continuously from May to October 1990. The allergen was extracted from the filters and immunochemically assayed for soybean aeroallergen. On 31 separate days, the airborne allergen concentration in at least one of the samples was over 10000 U/m3 similar to those observed in Barcelona on some epidemic days. Areas North and East of the elevator were most affected. Serologie studies showed that of 50 asthmatics from New Orleans who were participants in an unrelated clinical study 4 or 8% demonstrated elevated titers of IgE antibody to LMM soybean allergen. Only 1 of 475 control sera (half of which were also asthmatic) obtained elsewhere in the US was positive for LMM soybean IgE antibody. Based on the findings in this study, there is a great possibility that on some days there is enough soybean allergen in the air and a sufficient frequency of soybean aeroallergen RAST positive asthmatics in New Orleans to warrant further investigation of the contribution of soybean aeroallergen to asthma around the port of New Orleans.Supported by NIAID # A121255. Mayo Clinic and Foundation and Minnesota Lung Association. 相似文献
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Aims
Biocrusts that form on topsoils contribute ecosystem services to drylands, and their loss under anthropogenic pressure has negative ecological consequences. Therefore, development of biocrust inoculation technology for restoration is of interest. This requires knowledge of biocrust growth and dispersal. To contribute to this, we determined the speed at which biocrusts expand laterally based on the self-propelled motility of cyanobacteria.Methodology
We inoculated sterile soil with natural biocrusts and incubated them over a year in a greenhouse under conditions mimicking local precipitation, monitoring the crust’s lateral expansion using time-course photography, chlorophyll a content, and microscopic inspection. Concurrent uninoculated controls served to monitor, and discount, natural inoculation by aeolian propagules.Results
While the expansion front was highly variable in space, biocrusts expanded in the order of 2 cm month?1, but only in seasons with moderate temperatures (Spring and Fall). Microcoleus vaginatus, Microcoleus steenstrupii, and Scytonema spp. advanced at averages of 1 cm month?1, the crust advance front being preferentially driven by specialized propagules (hormogonia). These rates are within expectations based on instantaneous gliding motility speeds of cyanobacteria.Conclusions
Based on the expansion capability of biocrusts during growth seasons, greenhouse inoculum units can be optimally spaced to fill 4–8 cm gaps.45.
Anna Boladeras Ferran Ferrer Valentin Navarro Rodolfo De Blas Oriol Cunillera David Mateo Cristina Gutierrez Evelyn Martinez Salvador Villà Joan Pera Montse Ferrer Ferran Guedea 《Reports of Practical Oncology and Radiotherapy》2018,23(5):360-368
Aim
To evaluate the association between dose–volume histogram (DVH) values in organs at risk (OAR) and patient-reported HRQoL outcomes.Background
Data on the association between DVHs and health-related quality of life (HRQoL) in prostate cancer (PCa) patients are limited.Materials and methods
Five-year follow-up study of 154 patients with organ-confined (stage T1/T2) PCa treated with EBRT between January 2003 and November 2005. HRQoL was evaluated with the Expanded Prostate Cancer Index (EPIC). DVH for OARs (penile bulb, rectum and bladder) were created for all patients for whom data were available (119/154; 77%). The functional data analysis (FDA) statistical method was used. HRQoL data was collected prospectively and data analysis was performed retrospectively.Results
Worsening of urinary incontinence and obstructive symptoms correlated with higher DVH dose distributions at 24 months. Increased rectal bleeding at months 24 and 60 correlated with higher DVH dose distributions in the 40–70?Gy range. Patients with deterioration in rectal incontinence presented a higher DVH distribution range than patients without rectal incontinence. Penile bulb DVH values and erectile dysfunction were not significantly associated.Conclusions
DVH parameters and post-radiotherapy HRQoL appear to be closely correlated, underscoring the importance of assessing DVH values prior to initiating EBRT to determine the risk of developing HRQoL related adverse effects. Advanced treatment modalities may be appropriate in high risk cases to minimize treatment-related toxicity and to improve treatment outcomes and HRQoL. Future studies are needed to better elucidate the association between pre-treatment DVH parameters in organs at risk and subsequent HRQoL. 相似文献46.
The impact of endogenous content,replicates and pooling on genome capture from faecal samples
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Jessica Hernandez‐Rodriguez Mimi Arandjelovic Jack Lester Cesare de Filippo Antje Weihmann Matthias Meyer Samuel Angedakin Ferran Casals Arcadi Navarro Linda Vigilant Hjalmar S. Kühl Kevin Langergraber Christophe Boesch David Hughes Tomas Marques‐Bonet 《Molecular ecology resources》2018,18(2):319-333
Target‐capture approach has improved over the past years, proving to be very efficient tool for selectively sequencing genetic regions of interest. These methods have also allowed the use of noninvasive samples such as faeces (characterized by their low quantity and quality of endogenous DNA) to be used in conservation genomic, evolution and population genetic studies. Here we aim to test different protocols and strategies for exome capture using the Roche SeqCap EZ Developer kit (57.5 Mb). First, we captured a complex pool of DNA libraries. Second, we assessed the influence of using more than one faecal sample, extract and/or library from the same individual, to evaluate its effect on the molecular complexity of the experiment. We validated our experiments with 18 chimpanzee faecal samples collected from two field sites as a part of the Pan African Programme: The Cultured Chimpanzee. Those two field sites are in Kibale National Park, Uganda (N = 9) and Loango National Park, Gabon (N = 9). We demonstrate that at least 16 libraries can be pooled, target enriched through hybridization, and sequenced allowing for the genotyping of 951,949 exome markers for population genetic analyses. Further, we observe that molecule richness, and thus, data acquisition, increase when using multiple libraries from the same extract or multiple extracts from the same sample. Finally, repeated captures significantly decrease the proportion of off‐target reads from 34.15% after one capture round to 7.83% after two capture rounds, supporting our conclusion that two rounds of target enrichment are advisable when using complex faecal samples. 相似文献
47.
Impacts of Mercury on Freshwater Fish-Eating Wildlife and Humans 总被引:1,自引:0,他引:1
This paper reviews the current state of knowledge of the toxic effects of mercury on fish-eating birds, mammals, and humans associated with freshwater ecosystems, including new information on the relative risk of elevated methyl Hg exposure for fish-eating birds inhabiting aquatic ecosystems impacted by mining/smelting activities and areas characterized by high geological sources of Hg. The influence of various environmental conditions such as lake pH, DOC, and chemical speciation of Hg, on fish-Hg concentrations and Hg exposure in fish-eating wildlife, are discussed. Although a continuing global effort to decrease the release of this nonessential metal into the environment is warranted, Hg methylation and biomagnification may be limited in some environments due to chemical speciation of mercury in soils and sediments (e.g., HgS) and water quality conditions (e.g., high alkalinity and pH) that do not facilitate high methylation rates. We have shown such limitations for a lake where historic Hg mining greatly increased sediment-Hg loadings, yet Hg increases in small fish of various species are currently lower than expected, and top predators (bald eagles), despite having elevated concentrations of Hg in their blood compared with individuals from nearby lakes, exhibit no Hg-related reproductive impairment or other signs of MeHg intoxication. Recent epidemiological studies have shown that fish-eating human populations may be exposed to Hg sufficient to cause significant developmental effects. However, for humans, we conclude that the current USEPA reference dose for MeHg may be too restrictive, particularly for the less sensitive adult. The health status of indigenous peoples relying on the subsistence harvest of wild foods may be negatively affected by such restrictions. 相似文献
48.
We describe a population of colonial cyanobacteria (waterwarts) that develops as the dominant primary producer in a bottom‐fed, O2‐poor, warm spring in the Cuatro Ciénegas karstic region of the Mexican Chihuahuan Desert. The centimeter‐sized waterwarts were suspended within a central, conically shaped, 6‐m deep well by upwelling waters. Waterwarts were built by an Aphanothece‐like unicellular cyanobacterium and supported a community of epiphytic filamentous cyanobacteria and diatoms but were free of heterotrophic bacteria inside. Sequence analysis of 16S rRNA genes revealed that this cyanobacterium is only distantly related to several strains of other unicellular cyanobacteria (Merismopedia, Cyanothece, Microcystis). Waterwarts contained orderly arrangements of mineral crystallites, made up of microcrystalline low‐magnesium calcite with high levels of strontium and sulfur. Waterwarts were 95.9% (v/v) glycan, 2.8% cells, and 1.3% mineral grains and had a buoyant density of 1.034 kg·L?1. An analysis of the hydrological properties of the spring well and the waterwarts demonstrated that both large colony size and the presence of controlled amounts of mineral ballast are required to prevent the population from being washed out of the well. The unique hydrological characteristics of the spring have likely selected for both traits. The mechanisms by which controlled nucleation of extracellular calcite is achieved remain to be explored. 相似文献
49.
Measles Virus Fusion Protein Is Palmitoylated on Transmembrane-Intracytoplasmic Cysteine Residues Which Participate in Cell Fusion 总被引:4,自引:2,他引:2
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Monserrat Caballero Juan Carabaa Javier Ortego Rafael Fernndez-Muoz María L. Celma 《Journal of virology》1998,72(10):8198-8204
[3H]palmitic acid was metabolically incorporated into the viral fusion protein (F) of Edmonston or freshly isolated measles virus (MV) during infection of human lymphoid or Vero cells. The uncleaved precursor F0 and the F1 subunit from infected cells and extracellular virus were both labeled, indicating that palmitoylation can take place prior to F0 cleavage and that palmitoylated F protein was incorporated into virus particles. [3H]palmitic acid was released from F protein upon hydroxylamine or dithiothreitol treatment, indicating a thioester linkage. In cells transfected with the cloned MV F gene, in which the cysteines located in the intracytoplasmic and transmembrane domains (Cys 506, 518, 519, 520, and 524) were replaced by serine, a major reduction of [3H]palmitic acid incorporation was observed for F mutated at Cys 506 and, to a lesser extent, at Cys 518 and Cys 524. We also observed incorporation of [3H]palmitic acid in the F1 subunit of canine distemper virus F protein. Cell fusion induced by cotransfection of cells with MV F and H (hemagglutinin) genes was significantly reduced after replacement of Cys 506 or Cys 519 with serine in the MV F gene. Transfection with the F gene with a mutation for Cys 518 abolished cell fusion, although less mutant protein was detected on the cell surface. These results suggest that the F protein transmembrane domain cysteines 506 and 518 participate in structures involved in cell fusion, possibly mediated by palmitoylation. 相似文献
50.