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71.
Vivian Fransozo Daniela Carvalho dos Santos Laura Suzana López-Greco Eduardo Antonio Bolla Júnior 《Invertebrate reproduction & development.》2013,57(1):6-15
The development of secondary sexual characters, the petasma, and thelycum growth were studied in Xiphopenaeus kroyeri. In adult females, the thelycum is a single plate and its anterolateral portion is characterized by a reduced hood. The aperture resembles a transverse ridge. In immature stages, the ridge has a space between the plates, which becomes narrower as it reaches the end of development. The female gonopore is ‘comma’ shaped. In adult males, the endopods of the petasma are linked at the dorsomedial margin by a large quantity of cincinnuli. In juveniles, cincinnuli gradually increase in number until they join both endopods. At the end of development the petasma is T-shaped. The male gonopore is C-shaped. The relative growth of the petasma total length versus juvenile body length showed a highly positive allometry, whereas in adults the growth was isometric. For the relationship carapace length versus thelycum width, the juvenile phase of females is characterized by an isometry and the adult phase by a negative allometry. 相似文献
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73.
Eduardo L. V. Silveira Mark H. Fogg Rachel M. Leskowitz Hildegund C. Ertl Roger W. Wiseman David H. O'Connor Paul Lieberman Fred Wang Francois Villinger 《Journal of virology》2013,87(24):13904-13910
Epstein-Barr virus (EBV) is a vaccine/immunotherapy target due to its association with several human malignancies. EBNA-1 is an EBV protein consistently expressed in all EBV-associated cancers. Herein, EBNA-1-specific T cell epitopes were evaluated after AdC–rhEBNA-1 immunizations in chronically lymphocryptovirus-infected rhesus macaques, an EBV infection model. Preexisting rhEBNA-1-specific responses were augmented in 4/12 animals, and new epitopes were recognized in 5/12 animals after vaccinations. This study demonstrated that EBNA-1-specific T cells can be expanded by vaccination. 相似文献
74.
Xuan Li Eduardo Ximenes Mary Anne Roshni Amalaradjou Hunter B. Vibbert Kirk Foster Jim Jones Xingya Liu Arun K. Bhunia Michael R. Ladisch 《Applied and environmental microbiology》2013,79(22):7048-7054
This paper reports an approach to enable rapid concentration and recovery of bacterial cells from aqueous chicken homogenates as a preanalytical step of detection. This approach includes biochemical pretreatment and prefiltration of food samples and development of an automated cell concentration instrument based on cross-flow microfiltration. A polysulfone hollow-fiber membrane module having a nominal pore size of 0.2 μm constitutes the core of the cell concentration instrument. The aqueous chicken homogenate samples were circulated within the cross-flow system achieving 500- to 1,000-fold concentration of inoculated Salmonella enterica serovar Enteritidis and naturally occurring microbiota with 70% recovery of viable cells as determined by plate counting and quantitative PCR (qPCR) within 35 to 45 min. These steps enabled 10 CFU/ml microorganisms in chicken homogenates or 102 CFU/g chicken to be quantified. Cleaning and sterilizing the instrument and membrane module by stepwise hydraulic and chemical cleaning (sodium hydroxide and ethanol) enabled reuse of the membrane 15 times before replacement. This approach begins to address the critical need for the food industry for detecting food pathogens within 6 h or less. 相似文献
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76.
The stridulatory organ of the Crematogaster scutellaris (Olivier 1792) workers is being described, comparing their pars stridens present in six nests of this species, with one nest of Crematogaster auberti Emery 1869 and with the bibliographical data regarding other neighbouring species at our disposal. Both species and some Crematogaster scutellaris nests have shown significant differences. We propose several hypotheses which could explain these differences. 相似文献
77.
Randall E. Mielke John H. Priester Rebecca A. Werlin Jeff Gelb Allison M. Horst Eduardo Orias Patricia A. Holden 《Applied and environmental microbiology》2013,79(18):5616-5624
Nanoscale titanium dioxide (TiO2) is increasingly used in consumer goods and is entering waste streams, thereby exposing and potentially affecting environmental microbes. Protozoans could either take up TiO2 directly from water and sediments or acquire TiO2 during bactivory (ingestion of bacteria) of TiO2-encrusted bacteria. Here, the route of exposure of the ciliated protozoan Tetrahymena thermophila to TiO2 was varied and the growth of, and uptake and accumulation of TiO2 by, T. thermophila were measured. While TiO2 did not affect T. thermophila swimming or cellular morphology, direct TiO2 exposure in rich growth medium resulted in a lower population yield. When TiO2 exposure was by bactivory of Pseudomonas aeruginosa, the T. thermophila population yield and growth rate were lower than those that occurred during the bactivory of non-TiO2-encrusted bacteria. Regardless of the feeding mode, T. thermophila cells internalized TiO2 into their food vacuoles. Biomagnification of TiO2 was not observed; this was attributed to the observation that TiO2 appeared to be unable to cross the food vacuole membrane and enter the cytoplasm. Nevertheless, our findings imply that TiO2 could be transferred into higher trophic levels within food webs and that the food web could be affected by the decreased growth rate and yield of organisms near the base of the web. 相似文献
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79.
Eduardo V. Soares Helena M. V. M. Soares 《Applied microbiology and biotechnology》2013,97(15):6667-6675
Heavy metal pollution is a matter of concern in industrialised countries. Contrary to organic pollutants, heavy metals are not metabolically degraded. This fact has two main consequences: its bioremediation requires another strategy and heavy metals can be indefinitely recycled. Yeast cells of Saccharomyces cerevisiae are produced at high amounts as a by-product of brewing industry constituting a cheap raw material. In the present work, the possibility of valorising this type of biomass in the bioremediation of real industrial effluents containing heavy metals is reviewed. Given the auto-aggregation capacity (flocculation) of brewing yeast cells, a fast and off-cost yeast separation is achieved after the treatment of metal-laden effluent, which reduces the costs associated with the process. This is a critical issue when we are looking for an effective, eco-friendly, and low-cost technology. The possibility of the bioremediation of industrial effluents linked with the selective recovery of metals, in a strategy of simultaneous minimisation of environmental hazard of industrial wastes with financial benefits from reselling or recycling the metals, is discussed. 相似文献