PURPOSE: The purpose of part I of this study was to differentiate among Aramany class I obturators of 4 designs regarding retention and associated stress using numerical and experimental methods.
MATERIAL AND METHODS: Four finite element models and 36 different base obturators were fabricated and divided into 9 acrylic resin bases retained with Adams clasps and 9 linear, 9 tripodal, and 9 fully tripodal design obturators from casts obtained from a scanned skull. After modification, the prostheses were fabricated on the casts obtained from a 3-dimensionally printed cast. The retention was evaluated, and the data were collected and analyzed using a statistical software program (α=.05). The displacement and associated stress in the assorted casts were compared by using 5-N displacing force at 3 points using finite element analysis. The quantitative assessment was made by measuring the displacement and von Mises stress distribution on the prostheses and their supporting structures. The qualitative analysis was done by using a visual color mapping to depict stress location and intensity.
RESULTS: No significant differences were found between fully tripodal (4.478 ±2.303 MPa) and tripodal obturators (4.478 ±2.286 MPa; P=.153), although fully tripodal showed more resistance to anterior displacement (4.522 ±0.979 and 3.553 ±1.58 MPa for fully tripodal and tripodal designs, respectively; P=.007), and tripodal obturators produced more resistance to middle displacement (5.441 ±1.778 and 2.784 ±0.432 MPa for tripodal and fully tripodal design respectively; P=.001). The fully tripodal obturator showed more retention (3.736 ±1.182 MPa) than the linear one (2.493 ±1.052 MPa; P=.001). The maxillary central incisor was the most stressed abutment, followed by the lateral incisor, while the second molar was the least.
CONCLUSIONS: Regarding retention, the fully tripodal obturator produces retention comparable with the tripodal and significantly more than the linear. Acrylic resin prostheses retained with Adams clasps may be similar to metal-based prostheses regarding retention and stress distribution on the supporting structures.
METHODS: Cervical cancer policies in six developing countries from each WHO region were selected while related data from the Cervical Cancer Country Profiles 2021 by WHO were retrieved for comparison.
RESULTS: The cervical cancer policies that were included in this review were from Malaysia, Thailand, Iran, Kenya, Argentina, and Ukraine. According to the latest guidelines on the management of cervical cancers, WHO recommendations have been elaborated on primary, secondary, and tertiary prevention. A comparison of policies among these selected countries showed variation in each level of prevention. The cancer burden in each country was also found to determine the progression of cervical cancer prevention and policy controls in these countries.
CONCLUSION: This review emphasizes the dissimilarities of cervical cancer policies in six developing countries compared to recommendations by the WHO. Identifying these discrepancies could help policymakers in developing nations to recognize the pressing issues surrounding cervical cancer prevention and establish more effective prevention and control approaches.
OBJECTIVES: To establish a simple, efficient, and optimized method to produce a G6PDViangchan variant and characterize the phenotypes of recombinant human wild-type G6PD and G6PDViangchan.
METHODS: G6PD was amplified by polymerase chain reaction (PCR) from a human cDNA plasmid, and the gene for G6PDViangchan was amplified by initiating a mutation at location 871 (G>A) through site-directed mutagenesis. Protein expression and western blotting were conducted after successful cloning. The enzymatic activity of both proteins was assessed spectrophotometrically after purification.
RESULTS: Both amplicons were successfully cloned into a pET26b(+) expression vector and transformed into Escherichia coli BL21 (DE3) cells for overexpression as C-terminally histidine-tagged recombinant proteins. Western blotting confirmed that both proteins were successfully produced at similar levels. The enzymes were purified by immobilized metal (Co) affinity chromatography. Postpurification assay of enzyme activity revealed about 2-fold differences in the levels of specific activity between the wild-type G6PD (155.88 U/mg) and G6PDViangchan (81.85 U/mg), which is consistent with earlier reports. Analysis in silico showed that the coding change in G6PDViangchan has a substantial effect on protein folding structure.
CONCLUSIONS: We successfully cloned, expressed, and purified both wild-type G6PD and G6PDViangchan proteins. Such a protocol may be useful for creating a model system to study G6PD deficiency disease.