A clean way to overcome environmental pollution is biodegradation. In this perspective, at the intersection of biodegradation and metagenomics, the degradome is defined as the totality of genes related to the biodegradation of a certain compound. It includes the genetic elements from both culturable and uncultured microorganisms. The possibility of assessing the biodegradation potential of an environmental samples, using a degradome-based polymerase chain reaction, was explored. 2,4-Dichlorophenol (2,4-DCP) was chosen as a model and the use of tfdB gene as a biodegradation marker was confirmed by bioinformatics study of TfdB protein. Five primer pairs were designed for the detection of different tfdB gene families. A total of 16 environmental samples were collected from Egyptian agricultural soils and wastewaters and tested for the presence of 2,4-DCP. The biodegradation capacity of 2,4-DCP was determined, for all isolated consortia, to reach up to 350 mg/l. Metagenomic DNA was extracted directly from the soil samples while successive 2,4-DCP-degrading microbial communities were enriched, with increasing concentrations of 2,4-DCP, then their DNA was extracted. The extracted DNA was tested for the distribution of the tfdB gene using a degradome-based polymerase chain reaction. tfdB-1 and tfdB-2 were detected in 5 and 9 samples, respectively. However, the co-existence of both genes was detected only in five samples. All tfdB positive samples were capable of 2,4-DCP degradation. The developed approach of assessing the potential of different environments for degrading 2,4-DCP was successfully measured in terms of accuracy (81.25%) and specificity (100%).

This study investigated the color stability and microhardness of five composites exposed to four beverages with different pH values. Composite discs were produced (n=10); Filtek Z250 (3M ESPE) and Filtek P90 (3M ESPE) were applied in two layers (2 mm, 20 seconds), and Tetric N-Ceram Bulk Fill (TetricBF, Ivoclar Vivadent) and SonicFill (Kerr) were applied in bulk (4 mm) and then light cured (40 seconds, Ortholux-LED, 1600 mW/cm). Indirect composite Sinfony (3M ESPE) was applied in two layers (2 mm) and cured (Visio system, 3M ESPE). The specimens were polished and tested for color stability; ΔE was calculated using spectrophotometer readings. Vickers microhardness (50 g, dwell time=45 seconds) was assessed on the top and bottom surfaces at baseline, 40 days of storage, subsequent repolishing, and 60 days of immersion in distilled water (pH=7.0), Coca-Cola (pH=2.3), orange juice (pH=3.75), or anise (pH=8.5) using scanning electron microscopy (SEM). The materials had similar ΔE values (40 days, p>0.05), but TetricBF had a significantly greater ΔE than P90 or SF (40 days). The ΔE was less for P90 and TetricBF than for Z250, SonicFill, and Sinfony (60 days). Repolishing and further immersion significantly affected the ΔE (p<0.05) except for P90. All composites had significantly different top vs bottom baseline microhardnesses. This was insignificant for the Z250/water, P90/orange juice (40 days), and Sinfony groups (40 and 60 days). Immersion produced variable time-dependent deterioration of microhardness in all groups. Multivariate repeated measures analysis of variance with post hoc Bonferroni tests were used to compare the results. ΔE and microhardness changes were significantly inversely correlated at 40 days, but this relationship was insignificant at 60 days (Pearson test). SEM showed degradation (40 days) that worsened (60 days). Bulk-fill composites differ regarding color-stability and top-to-bottom microhardness changes compared with those of other composites. P90 showed better surface degradation resistance. In conclusion, bulk-fill composites are not promising alternatives to incremental and indirect composites regarding biodegradation.

PURPOSE: Developmental dysplasia of the hip (DDH) is a term used to cover a broad spectrum of anomalies ranging from mild dysplasia to high-riding dislocations. We report the management of DDH in children using the Dega osteotomy and their long-term follow-up.

METHODS: Fifty-eight hips from 48 children younger than 8 years treated using the Dega osteotomy between January 1988 and October 2000 were included in this multcenter study. Both prospective (41 hips) and retrospective (17 hips) cases were included, and follow-up was for a minimum of 13 years. Radiographs were made preoperatively, immediately postoperatively, after 6 weeks or at removal of the spica cast if any, at 6-month intervals and/or as indicated for 3 years postoperatively and then on annual basis until the last follow-up. A single-cut computed tomographic scan was performed for all prospective patients. Special attention was paid to the predictive measures of hip arthrosis and the survival of the hip after Dega osteotomy.

RESULTS: The final clinical outcome was favorable in 44 hips (75.9 %). Eleven hips needed a second surgery (acetabuloplasty and/or arthroplasty) during the follow-up period.

CONCLUSIONS: In our pediatric patient population the Dega osteotomy proved to be an adequate measure for the management of this complex condition. The worst complication was avascular necrosis, and all of the affected hips ended with failure (pain, another surgery, or both).