A comparison between forefoot plaster and wooden soled shoes following Mitchell's osteotomy for hallux valgus.
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Between 1 October 1997 and 1 November 1998, 43 patients (59 feet) were treated with a standard Mitchell's osteotomy for hallux valgus. Of these, 26 patients (36 feet) were treated postoperatively in a forefoot plaster. The other 17 patients (23 feet) were treated with a wooden soled shoe. There was no significant difference between the 2 groups for age, indication for surgery, pre-operative deformity or grade of the operating surgeon. There was no significant difference in the mean time immobilised, mean time to union or complications. The patients were interviewed by telephone after a mean follow-up of 9.4 months. There was no significant difference in results between the 2 groups. This suggests that a forefoot plaster following Mitchell's osteotomy is unnecessary. Postoperative mobilisation in a wooden soled shoe can be used as an alternative. (+info)
Simultaneous suppression of multiple genes by single transgenes. Down-regulation of three unrelated lignin biosynthetic genes in tobacco.
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Many reports now describe the manipulation of plant metabolism by suppressing the expression of single genes. The potential of such work could be greatly expanded if multiple genes could be coordinately suppressed. In the work presented here, we test a novel method for achieving this by using single chimeric constructs incorporating partial sense sequences for multiple genes to target suppression of two or three lignin biosynthetic enzymes. We compare this method with a more conventional approach to achieving the same end by crossing plants harboring different antisense transgenes. Our results indicate that crossing antisense plants is less straightforward and predictable in outcome than anticipated. Most progeny had higher levels of target enzyme activity than predicted and had lost the expected modifications to lignin structure. In comparison, plants transformed with the chimeric partial sense constructs had more consistent high level suppression of target enzymes and had significant changes to lignin content, structure, and composition. It was possible to suppress three target genes coordinately using a single chimeric construct. Our results indicate that chimeric silencing constructs offer great potential for the rapid and coordinate suppression of multiple genes on diverse biochemical pathways and that the technique therefore deserves to be adopted by other researchers. (+info)
Myxomycetes from upper Egypt.
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The results of the first inventory of Myxomycetes from the subtropical region Upper Egypt are reported. The substrates were wood, bark of living and dead tree and leaf litter. 20 species belonging to 17 genera of Myxomycetes were identified. Wood was the best substrate for Myxomycetes colonization. Ceratiomyxa fruticulosa, Didymiun melanospermum, Licea biforis and Lycogala epidendrum were the most common species. Brief description and classification of species are provided. (+info)
In vitro bioavailability of heavy metals in pressure-treated wood dust.
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Pressure treatment with chromium, copper, and arsenic (CCA) is the most prevalent method for protecting wood used in outdoor construction projects. Although these metals are tightly bound to the wood fibers and are not released under most conditions of use, we examined the bioavailability of metals in CCA pressure-treated wood dust in vitro. Cytotoxicity and metallothionein (MT) mRNA expression were examined in V79 Chinese hamster lung fibroblast cells incubated with respirable-size wood dust generated by sanding CCA-treated and untreated (control) Southern yellow pine. In colony survival studies, increased cytotoxicity (p < 0.05) occurred in V79 cells treated with CCA wood dust (351 +/- 77 microg/ml, mean +/- SE) compared with control wood dust (883 +/- 91 microg/ml). Increased cytotoxicity with CCA wood dust also occurred in an arsenic resistant subline of V79 cells, thus suggesting that arsenic was not responsible for the increased cytotoxicity. Metallothionein mRNA was significantly increased after 48 h of treatment with CCA wood dust compared with control wood dust. Incubation of CCA wood dust in cell culture media resulted in the transfer of copper, but not chromium or arsenic, into the media. Moreover, the treatment of cells with this filtered extract resulted in significantly increased metallothionein mRNA, suggesting that bioavailable copper is responsible for inducing metallothionein mRNA in V79 cells. Thus, these bioassays suggest that metals become bioavailable during in vitro culture of phagocytic V79 cells with CCA wood dust. (+info)
Labdane-type diterpenoids from the wood of Cunninghamia konishii.
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Five new labdane-type diterpenes, 12beta,19-dihydroxymanoyl oxide (1), 8(17),13-labdadien-12,15-olid-19-oic acid (2), 12,15-epoxy-8(17),13-labdadien-18-oic acid (3), 8alpha-hydroxy-11E,13Z-labdadien-15-al (4), and (13R)-13-hydroxy-8(17), 11E,14-labdatrien-18-oic acid (5) were isolated from the wood of Cunninghamia konishii. Their structures were elucidated by two-dimensional NMR spectroscopy. (+info)
Respiratory symptoms, lung function, and nasal cellularity in Indonesian wood workers: a dose-response analysis.
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OBJECTIVES: It was hypothesised that inflammation plays a dominant part in the respiratory effects of exposure to wood dust. The purpose of this study was to relate the nasal inflammatory responses of workers exposed to meranti wood dust to (a) levels of exposure, (b) respiratory symptoms and (c) respiratory function. METHODS: A cross sectional study was carried out in 1997 in a woodworking plant that used mainly meranti, among 982 workers exposed to different concentrations of wood dust. Personal sampling (n=243) of inhalable dust measurements indicated mean exposure in specific jobs, and enabled classification of 930 workers in three exposure classes (<2, 2-5, and >5 mg/m(3)) based on job title. Questionnaires were used to screen respiratory symptoms in the entire population. Lung function was measured with two different techniques, conventional flow-volume curves and the forced oscillation technique. Nasal lavage was done to assess inflammation in the upper respiratory tract. RESULTS: A negative trend between years of employment and most flow-volume variables was found in men, but not in women workers. Current exposure, however, was not related to spirometric outcomes, respiratory symptoms, or nasal cellularity. Some impedance variables were related to current exposure but also with better function at higher exposure. CONCLUSIONS: Exposure to meranti wood dust did not cause an inflammation in the upper respiratory tract nor an increase of respiratory symptoms or decrease of lung function. These data do not corroborate the hypothesis that inflammation plays a part in airway obstruction induced by wood dust. (+info)
Microbial utilization of Pinus radiata bark.
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A screening program using suspensions of ground bark in mineral salts media, or extracts prepared from ground bark by treating with hot water, sulfuric acid, ammonium hydroxide, or sodium hydroxide, yielded more than 200 pure cultures of fungi, yeasts, and bacteria. Only 38 of these have good growth on liquid bark media. All were filamentous fungi, although many bacteria and yeasts were among the cultures that failed to give appreciable growth. Species of Penicillium, Scopulariopsis, Aspergillus, Trichoderma, Cladosporium, and Fusarium were among the most actively growing cultures. Cell biomass yields, as measured by cell nitrogen determination, were too low for economic production of single cell protein. (+info)
Novel perspectives in wood certification and forensics: dry wood as a source of DNA.
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The importance of wood for human societies can hardly be understated. If dry wood were amenable to molecular genetic investigations, this could lead to major applications in wood forensics, certification, archaeology and palaeobotany. To evaluate the potential of wood for molecular genetic investigations, we have attempted to isolate and amplify, by PCR, DNA fragments of increasing size corresponding to all three plant genomes from different regions of 10 oak logs. Stringent procedures to avoid contamination with external DNA were used in order to demonstrate the authenticity of the fragments amplified. This authenticity was further confirmed by demonstrating genetic uniformity within each log using both nuclear and chloroplast microsatellites. For most wood samples DNA was degraded, and the sequences that gave the best results were those of small size and present in high copy number (chloroplast, mitochondrial, or repeated nuclear sequences). Both storage conditions and storage duration play a role in DNA conservation. Overall, this work demonstrates that molecular markers from all three plant genomes can be used for genetic analysis on dry oak wood, but outlines some limitations and the need for further evaluation of the potential of wood for DNA analysis. (+info)