- Browse by Author
Browsing by Author "Mah, James"
Now showing 1 - 2 of 2
Results Per Page
Sort Options
Item COVID-19: What do we know?(Elsevier, 2020-09-21) Marshall, Steve; Duryea, Michael; Huang, Greg; Kadioglu, Onur; Mah, James; Palomo, Juan Martin; Rossouw, Emile; Stappert, Dina; Stewart, Kelton; Tufekci, Eser; Orthodontics and Oral Facial Genetics, School of DentistryCoronavirus disease 2019 (COVID-19) is a global pandemic caused by the pathogen severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).1 Preliminary assessments suggest the virus is highly transmittable and infectious,2, 3, 4, 5, 6, 7 with similarities in nosocomial and super-spreading events seen with severe acute respiratory syndrome coronavirus 1 (SARS-CoV-1) in 2003.8 Patients infected with SARS-CoV-2 display a wide range of host responses including no symptoms, mild nonrespiratory symptoms, severe respiratory illness, or organ dysfunction and death.1,5 The American Association of Orthodontists Council on Scientific Affairs was charged with examining the literature to determine the best evidence for questions pertaining to COVID-19 and its impact on the practice of orthodontics.Item Genetic Factors in External Apical Root Resorption Associated with Orthodontic Treatment(2004-06) Al-Qawasmi, Riyad A.; Hartsfield, James K., Jr.; Everett, Eric T.; Roberts, W. Eugene; Foroud, Tatiana M.; Mah, JamesExternal apical root resorption (EARR) is a common sequela of orthodontic treatment, although it may also occur without orthodontic treatment. Despite rigorous investigation, no single factor or group of factors that directly causes root resorption has been identified. Experiment 1. A sample of 83 pairs of full siblings who had undergone orthodontic treatment was studied. Measurements were made of the longest maxillary central incisor, mandibular central incisor and mesial and distal roots of the mandibular first molars. Heritability estimates were generated by generalized liner models. Our results showed that the heritability estimate of the EARR was 64% on average. It was concluded that there was sufficient heritability for EARR to pursue genetic analysis. Experiment 2. Five polymorphic markers flanking or lying within the IL-IA , IL-JB, TNSALP, TNFA, and TNFRSFJ JA genes were used in a candidate gene approach to assess linkage and association with EARR in 38 pedigrees. Suggestive evidence for linkage between EARR and the polymorphic marker D18S64 was obtained with the analysis program MAPMAKER/SIBS (LOD score 2.51). The Q-TDT program showed highly significant (p = 0.0003) evidence of linkage disequilibrium of IL-1 B polymorphisms with EARR. Our analysis indicates that the JL -1 B polymorphism accounts for 15% of the total EARR variation. Experiment 3. Nine-week-old male mice were randomly selected as controls or for placement under anesthesia of an open coil spring ligated to the left maxillary first molar producing a force of approximately 25 g. The control (C) or treated (T) per strain were A/J (C=3,T=9), C57BL/6J (C=7,T=8), C3H/HeJ (C = 4,T=6), BALB/cJ (C=4,T=6), 129P3 /J (C=6,T=8), DBA/2J (C=8,T=9), SJL/J (C=8,T= 10), and AKR/J (C=9,T =8). Animals were sacrificed after nine days of treatment or control; maxillae were immediately removed, prepared, sectioned, mounted, stained with H&E, and observed microscopically at 1 OOX to determine root resorption. Mice were grouped into root resorption resistant (A/J, C57BL/6J and SJL/J); intermediate (C3H/HeJ and AKR/J); and susceptible (BALB/cJ, DBA/2J, and 129P3/J) strains. It was concluded that there were differential susceptibility or resistance to root resorption among inbred mouse strains, indicating that genotype is an influencing factor.