RESUMO
Extraneous DNA interferes with PCR studies of endophytic fungi. A procedure was developed with which to evaluate the removal of extraneous DNA. Wheat (Triticum aestivum) leaves were sprayed with Saccharomyces cerevisiae and then subjected to physical and chemical surface treatments. The fungal ITS1 products were amplified from whole tissue DNA extractions. ANOVA was performed on the DNA bands representing S. cerevisiae on the agarose gel. Band profile comparisons using permutational multivariate ANOVA (PERMANOVA) and non-metric multidimensional scaling (NMDS) were performed on DGGE gel data, and band numbers were compared between treatments. Leaf surfaces were viewed under variable pressure scanning electron microscopy (VPSEM). Yeast band analysis of the agarose gel showed that there was no significant difference in the mean band DNA quantity after physical and chemical treatments, but they both differed significantly (p < 0.05) from the untreated control. PERMANOVA revealed a significant difference between all treatments (p < 0.05). The mean similarity matrix showed that the physical treatment results were more reproducible than those from the chemical treatment results. The NMDS showed that the physical treatment was the most consistent. VPSEM indicated that the physical treatment was the most effective treatment to remove surface microbes and debris. The use of molecular and microscopy methods for the post-treatment detection of yeast inoculated onto wheat leaf surfaces demonstrated the effectiveness of the surface treatment employed, and this can assist researchers in optimizing their surface sterilization techniques in DNA-based fungal endophyte studies.
Assuntos
Endófitos/isolamento & purificação , Técnicas Microbiológicas/métodos , Esterilização/métodos , Triticum/microbiologia , DNA Fúngico/genética , DNA Fúngico/isolamento & purificação , DNA de Plantas/química , DNA de Plantas/genética , DNA Espaçador Ribossômico/genética , DNA Espaçador Ribossômico/isolamento & purificação , Eletroforese em Gel de Gradiente Desnaturante , Microscopia Eletrônica de Varredura , Folhas de Planta/microbiologia , Folhas de Planta/ultraestrutura , Reação em Cadeia da Polimerase , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/isolamento & purificação , Saccharomyces cerevisiae/ultraestrutura , Propriedades de Superfície , Triticum/ultraestruturaRESUMO
Extraneous DNA interferes with PCR studies of endophytic fungi. A procedure was developed with which to evaluate the removal of extraneous DNA. Wheat (Triticum aestivum) leaves were sprayed with Saccharomyces cerevisiae and then subjected to physical and chemical surface treatments. The fungal ITS1 products were amplified from whole tissue DNA extractions. ANOVA was performed on the DNA bands representing S. cerevisiae on the agarose gel. Band profile comparisons using permutational multivariate ANOVA (PERMANOVA) and non-metric multidimensional scaling (NMDS) were performed on DGGE gel data, and band numbers were compared between treatments. Leaf surfaces were viewed under variable pressure scanning electron microscopy (VPSEM). Yeast band analysis of the agarose gel showed that there was no significant difference in the mean band DNA quantity after physical and chemical treatments, but they both differed significantly (p < 0.05) from the untreated control. PERMANOVA revealed a significant difference between all treatments (p < 0.05). The mean similarity matrix showed that the physical treatment results were more reproducible than those from the chemical treatment results. The NMDS showed that the physical treatment was the most consistent. VPSEM indicated that the physical treatment was the most effective treatment to remove surface microbes and debris. The use of molecular and microscopy methods for the post-treatment detection of yeast inoculated onto wheat leaf surfaces demonstrated the effectiveness of the surface treatment employed, and this can assist researchers in optimizing their surface sterilization techniques in DNA-based fungal endophyte studies.
Assuntos
Endófitos/isolamento & purificação , Técnicas Microbiológicas/métodos , Esterilização/métodos , Triticum/microbiologia , Eletroforese em Gel de Gradiente Desnaturante , DNA Fúngico/genética , DNA Fúngico/isolamento & purificação , DNA Espaçador Ribossômico/genética , DNA Espaçador Ribossômico/isolamento & purificação , Microscopia Eletrônica de Varredura , Reação em Cadeia da Polimerase , Saccharomyces cerevisiae/genética , Triticum/ultraestruturaRESUMO
Extraneous DNA interferes with PCR studies of endophytic fungi. A procedure was developed with which to evaluate the removal of extraneous DNA. Wheat (Triticum aestivum) leaves were sprayed with Saccharomyces cerevisiae and then subjected to physical and chemical surface treatments. The fungal ITS1 products were amplified from whole tissue DNA extractions. ANOVA was performed on the DNA bands representing S. cerevisiae on the agarose gel. Band profile comparisons using permutational multivariate ANOVA (PERMANOVA) and non-metric multidimensional scaling (NMDS) were performed on DGGE gel data, and band numbers were compared between treatments. Leaf surfaces were viewed under variable pressure scanning electron microscopy (VPSEM). Yeast band analysis of the agarose gel showed that there was no significant difference in the mean band DNA quantity after physical and chemical treatments, but they both differed significantly (p < 0.05) from the untreated control. PERMANOVA revealed a significant difference between all treatments (p < 0.05). The mean similarity matrix showed that the physical treatment results were more reproducible than those from the chemical treatment results. The NMDS showed that the physical treatment was the most consistent. VPSEM indicated that the physical treatment was the most effective treatment to remove surface microbes and debris. The use of molecular and microscopy methods for the post-treatment detection of yeast inoculated onto wheat leaf surfaces demonstrated the effectiveness of the surface treatment employed, and this can assist researchers in optimizing their surface sterilization techniques in DNA-based fungal endophyte studies.
Assuntos
Endófitos/isolamento & purificação , Técnicas Microbiológicas/métodos , Esterilização/métodos , Triticum/microbiologia , Eletroforese em Gel de Gradiente Desnaturante , DNA Fúngico/genética , DNA Fúngico/isolamento & purificação , DNA de Plantas/química , DNA de Plantas/genética , DNA Espaçador Ribossômico/genética , DNA Espaçador Ribossômico/isolamento & purificação , Microscopia Eletrônica de Varredura , Reação em Cadeia da Polimerase , Folhas de Planta/microbiologia , Folhas de Planta/ultraestrutura , Propriedades de Superfície , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/isolamento & purificação , Saccharomyces cerevisiae/ultraestrutura , Triticum/ultraestruturaRESUMO
Down syndrome is commonly associated with significant congenital heart disease with the potential for early development of pulmonary hypertension. As such, children with Down syndrome may be at increased risk for both perioperative and long-term mortality. The purpose of this study, using data collected from a population-based outcomes study, is to analyze the potential role that Down syndrome plays in the outcome of surgically "corrected" congenital heart disease. Data were collected from a registry of all Oregon residents who, in the period 1958 to the present, had a reparative operation for one of 14 congenital cardiac malformations when younger than 18 years (N = 3965 patients). Down syndrome was present in 289 (7%) of the total registry patients. In evaluating the cardiac mortality associated with Down syndrome for each of the repaired cardiac malformations, only complete atrioventricular septal defect was associated with significantly higher perioperative (13% vs 5%) as well as higher overall late cardiac mortality through 20 years after the operation (20% vs 5%; p = 0.04). The survival outcomes for each of the other cardiac malformations were similar for children with and without Down syndrome.