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Root Treatment (root + treatment)
Selected AbstractsInduction of systemic resistance in Arabidopsis thaliana in response to a culture filtrate from a plant growth-promoting fungus, Phoma sp.PLANT BIOLOGY, Issue 1 2009GS8- Abstract The plant growth-promoting fungus (PGPF), Phoma sp. GS8-3, isolated from a zoysia grass rhizosphere, is capable of protecting cucumber plants against virulent pathogens. This fungus was investigated in terms of the underlying mechanisms and ability to elicit systemic resistance in Arabidopsis thaliana. Root treatment of Arabidopsis plants with a culture filtrate (CF) from Phoma sp. GS8-3 elicited systemic resistance against the bacterial speck pathogen Pseudomonas syringae pv. tomato DC3000 (Pst), with restricted disease development and inhibited pathogen proliferation. Pathway-specific mutant plants, such as jar1 (jasmonic acid insensitive) and ein2 (ethylene insensitive), and transgenic NahG plants (impaired in salicylate signalling) were protected after application of the CF, demonstrating that these pathways are dispensable (at least individually) in CF-mediated resistance. Similarly, NPR1 interference in npr1 mutants had no effect on CF-induced resistance. Gene expression studies revealed that CF treatment stimulated the systemic expression of both the SA-inducible PR-1 and JA/ET-inducible PDF1.2 genes. However, pathogenic challenge to CF-treated plants was associated with potentiated expression of the PR-1 gene and down-regulated expression of the PDF1.2 gene. The observed down-regulation of the PDF1.2 gene in CF-treated plants indicates that there may be cross-talk between SA- and JA/ET-dependent signalling pathways during the pathogenic infection process. In conclusion, our data suggest that CF of Phoma sp. GS8-3 induces resistance in Arabidopsis in a manner where SA and JA/ET may play a role in defence signalling. [source] Uptake and distribution of root-applied or foliar-applied 65Zn after flowering in aerobic riceANNALS OF APPLIED BIOLOGY, Issue 3 2007W. Jiang Abstract We investigated the uptake and distribution of zinc (Zn) either applied to the roots or to the leaves in rice during grain development. Plants of two aerobic rice cultivars were grown in a nutrient solution with either sufficient Zn or surplus Zn. Root treatment with 1 week,s supply of both 65Zn and unlabelled Zn was started at flowering or 15 days after flowering (DAF). Foliar treatment with 65Zn applied to the flag leaf or to senescent leaves was carried out at flowering. When 65Zn was applied to roots, plants continued to take up Zn after flowering, even beyond 15 DAF, irrespective of cultivar and Zn nutritional status of the plants. During the 1 week of supply of both 65Zn and unlabelled Zn, which either started at flowering or 15 DAF, the absorbed 65Zn was mainly distributed to roots, stem and grains. Little 65Zn was allocated to the leaves. Following a week of 65Zn supply directly after flowering, under sufficient Zn or surplus Zn, the proportions of total 65Zn uptake allocated to the grains continued to change during grain filling (9,33%). This Zn mainly came from the roots but under sufficient Zn supply also from the stem. With 65Zn applied to leaves (either the flag leaf or the lowest senescent leaf), both cultivars showed similar Zn distribution within the plants. About 45,50% of the 65Zn absorbed was transported out of the 65Zn-treated leaf. From that Zn, more than 90% was translocated to other vegetative organs; little was partitioned to the panicle parts and even less to the grains. These results suggest that in rice plants grown under sufficient or surplus Zn supply, most of the Zn accumulated in the grains originates from uptake by roots after flowering and not from Zn remobilisation from leaves. [source] Evaluation of the cost-effectiveness of root canal treatment using conventional approaches versus replacement with an implantINTERNATIONAL ENDODONTIC JOURNAL, Issue 10 2009M. W. Pennington Abstract Aim, To evaluate the cost-effectiveness of root canal treatment for a maxillary incisor tooth with a pulp infection, in comparison with extraction and replacement with a bridge, denture or implant supported restoration. Methodology, A Markov model was built to simulate the lifetime path of restorations placed on the maxillary incisor following the initial treatment decision. It was assumed that the goal of treatment was the preservation of a fixed platform support for a crown without involving the adjacent teeth. Consequently, the model estimates the lifetime costs and the total longevity of tooth and implant supported crowns at the maxillary incisor site. The model considers the initial treatment decisions, and the various subsequent treatment decisions that might be taken if initial restorations fail. Results, Root canal treatment extended the life of the tooth at an additional cost of £5,8 per year of tooth life. Provision of orthograde re-treatment, if the root canal treatment fails returns further extension of the expected life of the tooth at a cost of £12,15 per year. Surgical re-treatment is not cost-effective; it is cheaper, per year, to extend the life of the crown by replacement with a single implant restoration if orthograde endodontic treatment fails. Conclusion, Modelling the available clinical and cost data indicates that, root canal treatment is highly cost-effective as a first line intervention. Orthograde re-treatment is also cost-effective, if a root treatment subsequently fails, but surgical re-treatment is not. Implants may have a role as a third line intervention if re-treatment fails. [source] Periapical status and quality of endodontic treatment in an adult Irish populationINTERNATIONAL ENDODONTIC JOURNAL, Issue 2 2005J. J. Loftus Abstract Aim, To determine the prevalence of apical periodontitis and the quality of root fillings in an adult Irish population using a retrospective analysis of orthopantomograms (OPGs). Methodology, A systematic sample of clinical records and OPGs of 302 adult patients attending the Dublin Dental Hospital, Ireland, were screened by two examiners to determine the quality of root canal treatment and the prevalence of apical periodontitis. The operators who carried out the treatment were unknown. Two examiners inspected OPGs after inter-examiner correlation. European Society of Endodontology (ESE) guidelines were used to determine adequacy of root treatment. Results, Of the 7427 teeth examined 2% had root fillings. Apical periodontitis was evident in 1.6% of all nonroot filled teeth whilst 33.1% of the subjects had at least one tooth with apical periodontitis. Of the root filled teeth, 25% had apical periodontitis and 52.6% were considered technically inadequate by ESE guidelines. There was a statistically significant (P < 0.05) negative correlation between the quality of the root fillings and the prevalence of apical periodontitis. Posterior root filled teeth (premolars and molars) had a greater prevalence of apical periodontitis than anterior root filled teeth. Conclusions, The technical quality of root fillings in an adult Irish population was poor and was consistent with a high prevalence of apical periodontitis. [source] Comparative effectiveness of hand and ultrasonic instrumentations in root surface planing in vitroJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 3 2004Mahmood Khosravi Abstract Background/aims: A variety of techniques are employed for planing and scaling of the superficial root surfaces, of which hand and ultrasonic instrumentations have been preferentially used in routine periodontics clinics. This study was undertaken to compare the effectiveness of ultrasonic scalers and hand curettes in facilitating fibroblast attachment to the scaled root surfaces. Materials and Methods: Sixteen patients with periodontally involved teeth and nine subjects without periodontal diseases (control subjects) were selected. Two single-rooted teeth were extracted from each subject. Mesial and distal surfaces of teeth were selected in treated and untreated groups, respectively. The mesial surface of each tooth was randomly chosen to be treated either by hand curettes or ultrasonic instrumentation. The degree of cell attachment on the root surfaces of treated and untreated groups from control subjects and patients was then determined by the use of a gingival fibroblast line established and employed at early passages. The attachment and proliferation of gingival fibroblasts on the root surfaces were evaluated using neutral red assay and scanning electron microscopy (SEM). Results: Fibroblast survival and proliferation on the surfaces of untreated periodontally involved roots were found to be significantly lower compared with control untreated surfaces (p<0.0001) or treated surfaces from patients (p<0.0001). No significant difference, however, was observed between root surfaces treated either by hand curettes or ultrasonic scalers. Conclusion: These results indicate the beneficial effectiveness of both techniques in root treatment and planing. [source] Jasmonic acid treatment to part of the root system is consistent with simulated leaf herbivory, diverting recently assimilated carbon towards untreated roots within an hourPLANT CELL & ENVIRONMENT, Issue 9 2008GUNNAR JAKOB HENKES ABSTRACT It is known that shoot application of jasmonic acid (JA) leads to an increased carbon export from leaves to stem and roots, and that root treatment with JA inhibits root growth. Using the radioisotope 11C, we measured JA effects on carbon partitioning in sterile, split-root, barley plants. JA applied to one root half reduced carbon partitioning to the JA-treated tissue within minutes, whereas the untreated side showed a corresponding , but slower , increase. This response was not observed when instead of applying JA, the sink strength of one root half was reduced by cooling it: there was no enhanced partitioning to the untreated roots. The slower response in the JA-untreated roots, and the difference between the effect of JA and temperature, suggest that root JA treatment caused transduction of a signal from the treated roots to the shoot, leading to an increase in carbon allocation from the leaves to the untreated root tissue, as was indeed observed 10 min after the shoot application of JA. This supports the hypothesis that the response of some plant species to both leaf and root herbivores may be the diversion of resources to safer locations. [source] | |||||||||||||