Aim: To investigate the stress distribution on artificial atlantoaxial-odontoid joint (AAOJ) components during flexion, extension, lateral bending and rotation of AAOJ model constructed with the finite element (FE) method.
Material And Methods: Human cadaver specimens of normal AAOJ were CT scanned with 1 mm -thickness and transferred into Mimics software to reconstruct the three-dimensional models of AAOJ. These data were imported into Freeform software to place a AAOJ into a atlantoaxial model. With Ansys software, a geometric model of AAOJ was built. Perpendicular downward pressure of 40 N was applied to simulate gravity of a skull, then 1.53 N• m torque was exerted separately to simulate the range of motion of the model.
Results: An FE model of atlantoaxial joint after AAOJ replacement was constructed with a total of 103 053 units and 26 324 nodes. In flexion, extension, right lateral bending and right rotation, the AAOJ displacement was 1.109 mm, 3.31 mm, 0.528 mm, and 9.678 mm, respectively, and the range of motion was 1.6°, 5.1°, 4.6° and 22°.
Conclusion: During all ROM, stress distribution of atlas-axis changed after AAOJ replacement indicating that AAOJ can offload stress. The stress distribution in the AAOJ can be successfully analyzed with the FE method.
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http://dx.doi.org/10.5137/1019-5149.JTN.12681-14.0 | DOI Listing |
Genome
January 2025
Damietta University Faculty of Science, New Damietta, Damietta, Egypt;
Polyamine oxidase (PAOs) are enzymes associated with polyamine catabolism and play important roles in growth and development and stress tolerance of plants. In the present study, genome-wide discovery and analysis of the PAO family in sorghum was done utilizing model PAO of Arabidopsis. Six PAO genes were found using publicly available genomic data.
View Article and Find Full Text PDFElectromagn Biol Med
January 2025
Department of Mathematics, University of Gour Banga, Malda, India.
In cardiovascular research, electromagnetic fields generated by Riga plates are utilized to study or manipulate blood flow dynamics, which is particularly crucial in developing treatments for conditions such as arterial plaque deposition and understanding blood behavior under varied flow conditions. This research predicts the flow patterns of blood enhanced with gold and maghemite nanoparticles (gold-maghemite/blood) in an electromagnetic microchannel influenced by Riga plates with a temperature gradient that decays exponentially, under sudden changes in pressure gradient. The flow modeling includes key physical influences like radiation heat emission and Darcy drag forces in porous media, with the flow mathematically represented through unsteady partial differential equations solved using the Laplace transform (LT) method.
View Article and Find Full Text PDFmBio
January 2025
Department of Microbiology, Harvard Medical School, Boston, Massachusetts, USA.
The 55-carbon isoprenoid, undecaprenyl-phosphate (UndP), is a universal carrier lipid that ferries most glycans and glycopolymers across the cytoplasmic membrane in bacteria. In addition to peptidoglycan precursors, UndP transports O-antigen, capsule, wall teichoic acids, and sugar modifications. How this shared but limited lipid is distributed among competing pathways is just beginning to be elucidated.
View Article and Find Full Text PDFEnviron Sci Technol
January 2025
Stockbridge School of Agriculture, University of Massachusetts, Amherst, Massachusetts 01003, United States.
Concern over nanoplastic contamination of wetland ecosystems has been increasing. However, little is known about the effect of photoaging on the distribution and biological response of the nanoplastics. Here, palladium-labeled polystyrene nanoplastics (PS-Pd NPs) at 0.
View Article and Find Full Text PDFCurr Top Med Chem
January 2025
Medicinal Chemistry Department, Theodor Bilharz Research Institute Kornaish El Nile, Warrak El-Hadar, Imbaba (P.O. 30), Giza 12411, Egypt.
Background: Research into oxidative stress, cancer, and natural products revealed promising avenues for therapeutic intervention. Natural products are considered potent pharmaceuticals in combating oxidative stress and its relationship with cancer.
Methods: This study was carried out to evaluate the chemical profile and antioxidant activities using DPPH, ABTS, Phenanthroline, Cupric, Phosphomolybdenum, FRAP, Hydroxyl, Iron chelation in vitro assays, and anticancer properties by MTT method of Cistus creticus extracts.
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