Bacterial community structure in lake sediments of microcosms contaminated with nonylphenol     

Miriam Jontofsohn  Gerd Pfister  Gabriele Severin  Karl-Werner Schramm  Anton Hartmann  Michael Schloter 《Journal of Soils and Sediments》2002,2(4):211-215

The impact of nonylphenol, an estrogenic degradation product of alkylphenol polyethoxylates, on the bacterial community structure in contaminated sediments of aquatic microcosms was investigated over a period of 20 weeks using a 16S rDNA-based molecular phylogenetic approach. All microcosms showeda strong seasonal fluctuation of the dominant as well as the active bacterial microflora independent of their degree of contamination with nonylphenol. These changes were correlated with the dynamic of the total organic carbon content (TOC), ranging from 4–39 g/kg sediment dry weight and the redox potential in the sediment. Even at the highest observed nonylphenol concentration (3.4 mg/kg sediment dry weight) the bacterial community structure was mostly unchanged.  相似文献   

Protecting peppers from aphid-borne viruses with aluminum foil or plastic mulch     

G. Loebenstein  Miriam Alper  S. Levy  D. Palevitch  E. Menagem 《Phytoparasitica》1975,3(1):43-53

Aluminum foil and plastic mulch, covering 57-83% of the ground in peppers from emergence, effectively protected the crop against aphid-borne cucumber mosaic and potato virus Y by repelling winged aphids. Aluminum foil and grey plastic sheets gave the best results, followed closely by white plastic on black. The mulches were most efficient during the first 3 weeks in the field, after which they lost some of their reflectance. Trappings of winged aphids from the aluminum-covered plots during the first 3 weeks were only 2 and 5% of the control, and those in the grey-plastic-covered plots were between 6 and 12%.Myzus persicae was especially sensitive to reflection, and trappings in the aluminum and grey plastic plots during the first 3 weeks were less than 0.6 and 2% of the control, respectively. Repellence of winged aphids was correlated with virus incidence, especially during years with high natural virus spread; infection rates in the mulched plots at harvest time reached only 4.5-6% compared with 45% in the controls. As a result, yields were markedly higher except in the aluminum-mulched plot where in one season growth of plants was retarded, perhaps due to lower soil temperature.  相似文献   

Genome sequence diversity and clues to the evolution of variola (smallpox) virus     

Esposito JJ  Sammons SA  Frace AM  Osborne JD  Olsen-Rasmussen M  Zhang M  Govil D  Damon IK  Kline R  Laker M  Li Y  Smith GL  Meyer H  Leduc JW  Wohlhueter RM 《Science (New York, N.Y.)》2006,313(5788):807-812

Comparative genomics of 45 epidemiologically varied variola virus isolates from the past 30 years of the smallpox era indicate low sequence diversity, suggesting that there is probably little difference in the isolates' functional gene content. Phylogenetic clustering inferred three clades coincident with their geographical origin and case-fatality rate; the latter implicated putative proteins that mediate viral virulence differences. Analysis of the viral linear DNA genome suggests that its evolution involved direct descent and DNA end-region recombination events. Knowing the sequences will help understand the viral proteome and improve diagnostic test precision, therapeutics, and systems for their assessment.  相似文献   

Highly conserved protective epitopes on influenza B viruses   总被引：1，自引：0，他引：1  

C Dreyfus  NS Laursen  T Kwaks  D Zuijdgeest  R Khayat  DC Ekiert  JH Lee  Z Metlagel  MV Bujny  M Jongeneelen  R van der Vlugt  M Lamrani  HJ Korse  E Geelen  Ö Sahin  M Sieuwerts  JP Brakenhoff  R Vogels  OT Li  LL Poon  M Peiris  W Koudstaal  AB Ward  IA Wilson  J Goudsmit  RH Friesen 《Science (New York, N.Y.)》2012,337(6100):1343-1348

Identification of broadly neutralizing antibodies against influenza A viruses has raised hopes for the development of monoclonal antibody-based immunotherapy and "universal" vaccines for influenza. However, a substantial part of the annual flu burden is caused by two cocirculating, antigenically distinct lineages of influenza B viruses. Here, we report human monoclonal antibodies, CR8033, CR8071, and CR9114, that protect mice against lethal challenge from both lineages. Antibodies CR8033 and CR8071 recognize distinct conserved epitopes in the head region of the influenza B hemagglutinin (HA), whereas CR9114 binds a conserved epitope in the HA stem and protects against lethal challenge with influenza A and B viruses. These antibodies may inform on development of monoclonal antibody-based treatments and a universal flu vaccine for all influenza A and B viruses.  相似文献   

FEASIBILITY FOR USING DUAL‐PHASE CONTRAST‐ENHANCED MULTI‐DETECTOR HELICAL COMPUTED TOMOGRAPHY TO EVALUATE AWAKE AND SEDATED DOGS WITH ACUTE ABDOMINAL SIGNS     

Miriam M. Shanaman  Susan K. Hartman  Robert T. O'Brien 《Veterinary radiology & ultrasound》2012,53(6):605-612

Canine patients with acute abdominal signs are often clinically unstable and need a rapid and accurate diagnosis. Contrast‐enhanced multi‐detector computed tomography (CT) is the current modality of choice for evaluating acute abdominal pain in people. We hypothesized that contrast‐enhanced multi‐detector CT would be a feasible and safe technique for use in awake and lightly sedated dogs with acute abdominal signs. Eighteen client‐owned dogs were enrolled, all presenting with acute abdominal signs. Dogs were scanned using a dual‐phase protocol that included precontrast, arterial, and portal venous phases. Eight dogs were scanned awake and ten were given light sedation as chosen by the primary care clinician. Two observers who were unaware of clinical findings and sedation status scored image quality for each scan by consensus opinion. Mean serum creatinine in the sedated group was higher than in the awake group but was within the normal reference range. Other laboratory and physiologic measures did not differ between awake and sedated groups. No IV contrast‐related adverse reactions were seen. Median scan time for all patients was less than 10 min. Sixteen of 18 contrast‐enhanced multi‐detector CT scans were scored fair to excellent in diagnostic quality, with no statistical difference in diagnostic quality for awake vs. sedated patients. Causes for two poor quality diagnostic scans included severe beam hardening from previously administered barium contrast agent and severe motion artifacts. We conclude that dual‐phase contrast‐enhanced multi‐detector CT is a feasible and safe technique for evaluating awake and minimally sedated dogs presenting with acute abdominal signs.  相似文献   

Understanding foot-and-mouth disease virus transmission biology: identification of the indicators of infectiousness     

Margo E Chase-Topping  Ian Handel  Bartlomiej M Bankowski  Nicholas D Juleff  Debi Gibson  Sarah J Cox  Miriam A Windsor  Elizabeth Reid  Claudia Doel  Richard Howey  Paul V Barnett  Mark EJ Woolhouse  Bryan Charleston 《Veterinary research》2013,44(1):46

The control of foot-and-mouth disease virus (FMDV) outbreaks in non-endemic countries relies on the rapid detection and removal of infected animals. In this paper we use the observed relationship between the onset of clinical signs and direct contact transmission of FMDV to identify predictors for the onset of clinical signs and identify possible approaches to preclinical screening in the field. Threshold levels for various virological and immunological variables were determined using Receiver Operating Characteristic (ROC) curve analysis and then tested using generalized linear mixed models to determine their ability to predict the onset of clinical signs. In addition, concordance statistics between qualitative real time PCR test results and virus isolation results were evaluated. For the majority of animals (71%), the onset of clinical signs occurred 3–4 days post infection. The onset of clinical signs was associated with high levels of virus in the blood, oropharyngeal fluid and nasal fluid. Virus is first detectable in the oropharyngeal fluid, but detection of virus in the blood and nasal fluid may also be good candidates for preclinical indicators. Detection of virus in the air was also significantly associated with transmission. This study is the first to identify statistically significant indicators of infectiousness for FMDV at defined time periods during disease progression in a natural host species. Identifying factors associated with infectiousness will advance our understanding of transmission mechanisms and refine intra-herd and inter-herd disease transmission models.  相似文献   

The scale of landscape effect on seed dispersal depends on both response variables and landscape predictor     

San-José  Miriam  Arroyo-Rodríguez  Víctor  Jordano  Pedro  Meave  Jorge A.  Martínez-Ramos  Miguel 《Landscape Ecology》2019,34(5):1069-1080

Landscape Ecology - Landscape structure can affect seed dispersal, but the spatial scale at which such effect is maximized (scale of effect, SoE) is unknown. We assessed patterns and predictors of...  相似文献   

Contrast‐enhanced ultrasonography characteristics of intrathoracic mass lesions in 36 dogs and 24 cats     

Thorsten Rick  Miriam Kleiter  Ilse Schwendenwein  Eberhard Ludewig  Martin Reifinger  Katharina M. Hittmair 《Veterinary radiology & ultrasound》2019,60(1):56-64

Contrast‐enhanced ultrasonography (CEUS) is increasingly available for veterinary patients, however limited studies describe the use of this method for characterizing intrathoracic mass lesions. The aim of this prospective, observational study was to describe CEUS enhancement patterns for intrathoracic mass lesions in a sample of cats and dogs. Sixty patients (36 dogs, 24 cats) were included. Standardized CEUS examinations were performed for 41 pulmonary masses (68%) and 19 mediastinal masses (32%). Final diagnosis was based on cytology and/or histopathology. Absolute time to enhancement (TTE) values were recorded for the intrathoracic mass lesions and spleen. The spleen was used as a reference parenchymal organ to calculate relative TTE (rTTE) values. Absolute TTE of the spleen and intrathoracic mass lesions differed for dogs and cats (P = 0.001). The rTTE values significantly differed between lesions of neoplastic versus non‐neoplastic origin (P = 0.004). The majority of neoplastic pulmonary masses were supplied by bronchial arteries (63%), while most nonneoplastic pulmonary masses were supplied by pulmonary arteries (78%). The sensitivity and specificity for detecting pulmonary neoplastic masses with rTTE were 63% and 78%, respectively. Enhancement patterns for mediastinal thymomas and lymphomas significantly differed (P = 0.002). Thymomas enhanced heterogeneously in a centripetal pattern (86%), whereas lymphomas typically enhanced uniformly in a centrifugal pattern (75%). Findings indicated that CEUS is a feasible method for characterizing intrathoracic mass lesions in dogs and cats, however, the diagnostic sensitivity for detecting neoplastic pulmonary masses was low.  相似文献   

Genetic background of CTX‐M‐15‐producing Enterobacter hormaechei ST114 and Citrobacter freundii ST265 co‐infecting a free‐living green turtle (Chelonia mydas)     

Daphne W. Goldberg  Miriam R. Fernandes  Fbio P. Sellera  Daniela G. C. Costa  Ana Paula Loureiro Bracarense  Nilton Lincopan 《Zoonoses and public health》2019,66(5):540-545

CTX‐M‐type extended‐spectrum β‐lactamase (ESBL)‐producing Enterobacteriaceae have become identified in marine ecosystem constituting a serious ecological issue. In this respect, although contamination of coastal waters and seafood, and even colonization of seabirds and fishes have been increasingly reported, molecular data are lacking to elucidate the clinical impact of ESBL producers in infected marine animals. In this study, using a genomic approach, we have analysed the genetic background of CTX‐M‐15‐producing Enterobacter hormaechei (belonging to the international human clone ST114) and Citrobacter freundii (ST265) co‐infecting a free‐living green turtle (Chelonia mydas) suffering from septic arthritis, which progressed to generalized coelomitis and death. Wide resistome of these pathogens contributed to treatment failure and death of the animal.  相似文献   

Structural Characterization of New Peptide Variants Produced by Cyanobacteria from the Brazilian Atlantic Coastal Forest Using Liquid Chromatography Coupled to Quadrupole Time-of-Flight Tandem Mass Spectrometry     

Miriam Sanz  Ana Paula Dini Andreote  Marli Fatima Fiore  Felipe Augusto D?rr  Ernani Pinto 《Marine drugs》2015,13(6):3892-3919

Cyanobacteria from underexplored and extreme habitats are attracting increasing attention in the search for new bioactive substances. However, cyanobacterial communities from tropical and subtropical regions are still largely unknown, especially with respect to metabolite production. Among the structurally diverse secondary metabolites produced by these organisms, peptides are by far the most frequently described structures. In this work, liquid chromatography/electrospray ionization coupled to high resolution quadrupole time-of-flight tandem mass spectrometry with positive ion detection was applied to study the peptide profile of a group of cyanobacteria isolated from the Southeastern Brazilian coastal forest. A total of 38 peptides belonging to three different families (anabaenopeptins, aeruginosins, and cyanopeptolins) were detected in the extracts. Of the 38 peptides, 37 were detected here for the first time. New structural features were proposed based on mass accuracy data and isotopic patterns derived from full scan and MS/MS spectra. Interestingly, of the 40 surveyed strains only nine were confirmed to be peptide producers; all of these strains belonged to the order Nostocales (three Nostoc sp., two Desmonostoc sp. and four Brasilonema sp.).  相似文献