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Ambient Air Pollution, Asthma Drug Response and Telomere Length in African American Youth

Lee, Eunice Y; Oh, Sam S; White, Marquitta J; Eng, Celeste S; Elhawary, Jennifer R; Borrell, Luisa N; Nuckton, Thomas J; Zeiger, Andrew M; Keys, Kevin L; Mak, Angel C Y; Hu, Donglei; Huntsman, Scott; Contreras, Maria G; Samedy, Lesly-Anne; Goddard, Pagé C; Salazar, Sandra L; Brigino-Buenaventura, Emerita N; Davis, Adam; Meade, Kelley E; LeNoir, Michael A; Lurmann, Fred W; Burchard, Esteban G; Eisen, Ellen A; Balmes, John R
BACKGROUND:Telomere length can serve as a potential biomarker for conditions associated with chronic oxidative stress and inflammation such as asthma. Air pollution can induce oxidative stress. Understanding the relationship between telomere length, asthma, and air pollution is important for identifying risk factors contributing to unhealthy aging in children. OBJECTIVES/OBJECTIVE:To investigate the associations between exposures to ambient air pollutants and telomere length (TL) in African American children and adolescents, and to examine whether African ancestry, asthma status and steroid medication use alter the association. METHODS:) exposures in a cross-sectional analysis of 1,072 children in an existing asthma case-control study. African ancestry, asthma status and the use of steroid medications were examined as effect modifiers. RESULTS:were associated with shorter TL in patients without steroid use. CONCLUSION/CONCLUSIONS:Exposure to air pollution was associated with shorter telomere length in non-asthmatic children and adolescents. This was not the case for asthmatic children as a group, but those on steroid medication had less shortening than those not using steroids. Reduced exposure to air pollution in childhood may help to preserve telomere length.
PMID: 31247265
ISSN: 1097-6825
CID: 3954422

Preoperative Imaging for Facial Transplant: A Guide for Radiologists

Prabhu, Vinay; Plana, Natalie M; Hagiwara, Mari; Diaz-Siso, J Rodrigo; Lui, Yvonne W; Davis, Adam J; Sliker, Clint W; Shapiro, Maksim; Moin, Adnaan S; Rodriguez, Eduardo D
Facial transplant (FT) is a viable option for patients with severe craniomaxillofacial deformities. Transplant imaging requires coordination between radiologists and surgeons and an understanding of the merits and limitations of imaging modalities. Digital subtraction angiography and CT angiography are critical to mapping vascular anatomy, while volume-rendered CT allows evaluation of osseous defects and landmarks used for surgical cutting guides. This article highlights the components of successful FT imaging at two institutions and in two index cases. A deliberate stepwise approach to performance and interpretation of preoperative FT imaging, which consists of the modalities and protocols described here, is essential to seamless integration of the multidisciplinary FT team. ©RSNA, 2019 See discussion on this article by Lincoln .
PMID: 31125293
ISSN: 1527-1323
CID: 3921042

Secondhand smoke exposure and asthma outcomes among African-American and Latino children with asthma

Neophytou, Andreas M; Oh, Sam S; White, Marquitta J; Mak, Angel C Y; Hu, Donglei; Huntsman, Scott; Eng, Celeste; Serebrisky, Denise; Borrell, Luisa N; Farber, Harold J; Meade, Kelley; Davis, Adam; Avila, Pedro C; Thyne, Shannon M; Rodríguez-Cintrón, William; Rodríguez-Santana, José R; Kumar, Rajesh; Brigino-Buenaventura, Emerita; Sen, Saunak; Lenoir, Michael A; Williams, L Keoki; Benowitz, Neal L; Balmes, John R; Eisen, Ellen A; Burchard, Esteban G
BACKGROUND:Secondhand smoke (SHS) exposures have been linked to asthma-related outcomes but quantitative dose-responses using biomarkers of exposure have not been widely reported. OBJECTIVES/OBJECTIVE:Assess dose-response relationships between plasma cotinine-determined SHS exposure and asthma outcomes in minority children, a vulnerable population exposed to higher levels of SHS and under-represented in the literature. METHODS:We performed analyses in 1172 Latino and African-American children with asthma from the mainland USA and Puerto Rico. We used logistic regression to assess relationships of cotinine levels ≥0.05 ng/mL with asthma exacerbations (defined as asthma-related hospitalisations, emergency room visits or oral steroid prescription) in the previous year and asthma control. The shape of dose-response relationships was assessed using a continuous exposure variable in generalised additive logistic models with penalised splines. RESULTS:The OR for experiencing asthma exacerbations in the previous year for cotinine levels ≥0.05 ng/mL, compared with <0.05 ng/mL, was 1.40 (95% CI 1.03 to 1.89), while the OR for poor asthma control was 1.53 (95% CI 1.12 to 2.13). Analyses for dose-response relationships indicated increasing odds of asthma outcomes related with increasing exposure, even at cotinine levels associated with light SHS exposures. CONCLUSIONS:Exposure to SHS was associated with higher odds of asthma exacerbations and having poorly controlled asthma with an increasing dose-response even at low levels of exposure. Our results support the conclusion that there are no safe levels of SHS exposures.
PMID: 29899038
ISSN: 1468-3296
CID: 3351432

Genetic Determinants of Telomere Length in African American Youth

Zeiger, Andrew M; White, Marquitta J; Eng, Celeste; Oh, Sam S; Witonsky, Jonathan; Goddard, Pagé C; Contreras, Maria G; Elhawary, Jennifer R; Hu, Donglei; Mak, Angel C Y; Lee, Eunice Y; Keys, Kevin L; Samedy, Lesly-Anne; Risse-Adams, Oona; Magaña, Joaquín; Huntsman, Scott; Salazar, Sandra; Davis, Adam; Meade, Kelley; Brigino-Buenaventura, Emerita; LeNoir, Michael A; Farber, Harold J; Bibbins-Domingo, Kirsten; Borrell, Luisa N; Burchard, Esteban G
Telomere length (TL) is associated with numerous disease states and is affected by genetic and environmental factors. However, TL has been mostly studied in adult populations of European or Asian ancestry. These studies have identified 34 TL-associated genetic variants recently used as genetic proxies for TL. The generalizability of these associations to pediatric populations and racially diverse populations, specifically of African ancestry, remains unclear. Furthermore, six novel variants associated with TL in a population of European children have been identified but not validated. We measured TL from whole blood samples of 492 healthy African American youth (children and adolescents between 8 and 20 years old) and performed the first genome-wide association study of TL in this population. We were unable to replicate neither the 34 reported genetic associations found in adults nor the six genetic associations found in European children. However, we discovered a novel genome-wide significant association between TL and rs1483898 on chromosome 14. Our results underscore the importance of examining genetic associations with TL in diverse pediatric populations such as African Americans.
PMCID:6125592
PMID: 30185882
ISSN: 2045-2322
CID: 3271742

Perfusion and Permeability Imaging for Head and Neck Cancer: Theory, Acquisition, Postprocessing, and Relevance to Clinical Imaging

Davis, Adam J; Rehmani, Razia; Srinivasan, Ashok; Fatterpekar, Girish M
Perfusion and permeability computed tomography and MR imaging applied to head and neck cancer provide powerful diagnostic and prognostic tools for clinicians. Understanding the basics of these techniques allows the radiologist to make informed decisions regarding the use of modeling algorithms, acquisition parameters, and postprocessing techniques. This helps to ensure that studies are acquired, analyzed, and reported appropriately and erroneous results are avoided. These techniques are highly automated, widely available, and can be easily and safely incorporated into daily imaging workflow.
PMID: 29128004
ISSN: 1557-9786
CID: 2784742

Perceived Discrimination Associated With Asthma and Related Outcomes in Minority Youth: The GALA II and SAGE II Studies

Thakur, Neeta; Barcelo, Nicolas E; Borrell, Luisa N; Singh, Smriti; Eng, Celeste; Davis, Adam; Meade, Kelley; LeNoir, Michael A; Avila, Pedro C; Farber, Harold J; Serebrisky, Denise; Brigino-Buenaventura, Emerita; Rodriguez-Cintron, William; Thyne, Shannon; Rodriguez-Santana, Jose R; Sen, Saunak; Bibbins-Domingo, Kirsten; Burchard, Esteban Gonzalez
BACKGROUND:Asthma disproportionately affects minority populations and is associated with psychosocial stress such as racial/ethnic discrimination. We aimed to examine the association of perceived discrimination with asthma and poor asthma control in African American and Latino youth. METHODS:We included African American (n = 954), Mexican American (n = 1,086), other Latino (n = 522), and Puerto Rican Islander (n = 1,025) youth aged 8 to 21 years from the Genes-Environments and Admixture in Latino Americans study and the Study of African Americans, Asthma, Genes, and Environments. Asthma was defined by physician diagnosis, and asthma control was defined based on the National Heart, Lung, and Blood Institute guidelines. Perceived racial/ethnic discrimination was assessed by the Experiences of Discrimination questionnaire, with a focus on school, medical, and public settings. We examined the associations of perceived discrimination with each outcome and whether socioeconomic status (SES) and global African ancestry modified these associations. RESULTS:African American children reporting any discrimination had a 78% greater odds of experiencing asthma (OR, 1.78; 95% CI, 1.33-2.39) than did those not reporting discrimination. Similarly, African American children faced increased odds of poor asthma control with any experience of discrimination (OR, 1.97; 95% CI, 1.42-2.76) over their counterparts not reporting discrimination. These associations were not observed among Latino children. We observed heterogeneity of the association between reports of discrimination and asthma according to SES, with reports of discrimination increasing the odds of having asthma among low-SES Mexican American youth (interaction P = .01) and among high-SES other Latino youth (interaction P = .04). CONCLUSIONS:Perceived discrimination is associated with increased odds of asthma and poorer control among African American youth. SES exacerbates the effect of perceived discrimination on having asthma among Mexican American and other Latino youth.
PMID: 27916618
ISSN: 1931-3543
CID: 3346202

Continuous Versus Sequential Acquisition Head Computed Tomography: A Phantom and Clinical Image Quality Comparative Study

Davis, Adam J; Ozsvath, Jessica; Vega, Emilio; Babb, James S; Hagiwara, Mari; George, Ajax
OBJECTIVE: Sequential computed tomography (CT) technique remains the most common protocol for CT evaluation of the head despite nearly universal adoption of continuous technique for all other body parts. This may be attributable to the belief by radiologists that this technique is superior to helical scanning uniquely for this indication. This study attempts to clarify the issue. METHODS: A phantom evaluation and a prospective randomized clinical image quality trial were performed comparing sequential and helical technique using the most current generation 128-row detector CT scanner. RESULTS: Phantom evaluation demonstrated equivalence between the 2 techniques for low-contrast resolution and line pair spatial discrimination. Continuous scanning provided the highest contrast-to-noise ratio. There was no significant difference between the 2 techniques regarding image quality except for cortical visualization at the cerebral hemispheres, which was subtly but significantly superior for sequential technique. CONCLUSIONS: Head CT image quality for sequential and continuous techniques are virtually equivalent.
PMID: 26359580
ISSN: 1532-3145
CID: 1772632

Longitudinally Extensive Nitrous Oxide Myelopathy With Novel Radiographic Features

Ernst, Lia D; Brock, Kenneth; Barraza, Luis H; Davis, Adam; Nirenberg, Melissa J
PMID: 26368840
ISSN: 2168-6157
CID: 1779162

Measurement of Cochlear Implant Electrode Position From Intraoperative Post-insertion Skull Radiographs: A Validation Study

Svrakic, Maja; Friedmann, David R; Berman, Phillip M; Davis, Adam J; Roland, J Thomas Jr; Svirsky, Mario A
OBJECTIVE: To validate a method of measuring angular depth of insertion (aDOI) as well as positional depth of each electrode contact in a cochlear implant by using intraoperative postinsertion skull radiographs. STUDY DESIGN: Retrospective review. SETTING: Tertiary referral center. PATIENTS: Intraoperative postinsertion radiographs obtained from 18 cochlear implant recipients were chosen for analysis. One high-resolution computer tomography scan of the head with the electrode in place was also analyzed. One cadaveric temporal bone with an inserted electrode provided additional data for analysis. INTERVENTION: aDOI and position of each electrode contact were measured from the radiographs using readily available software. High-resolution computer tomography imaging of the cochlea and electrode were reconstructed in three dimensions and used to simulate head rotation during intraoperative radiographs. The cadaveric temporal bone was imaged by x-ray at various acquisition angles. MAIN OUTCOME MEASURES: We evaluated the error introduced in measuring aDOI by assessing intra- and inter-rater variability. We also evaluated the error introduced by x-ray acquisition at nonstandardized angles by analyzing the three-dimensional construct and the cadaveric temporal bone. RESULTS: The concordance correlation coefficients for intrarater (0.991) and inter-rater (0.996) variability in aDOI measurement were excellent. The error introduced by nonstandardized x-ray acquisition angles was only -12.5 degrees to +15.8 degrees even at the limits of clinically relevant head rotation. CONCLUSIONS: The intraoperative postinsertion radiograph is sufficient for estimating positional depth of electrode contacts and the aDOI. This measure is robust in the face of nonstandardized x-ray acquisition angles, and shows good intra- and inter-rater variability.
PMCID:4574306
PMID: 26375970
ISSN: 1537-4505
CID: 1778232

Repeatability and clinical utility in stereophotogrammetric measurements of wounds

Davis, A J; Nishimura, J; Seton, J; Goodman, B L; Ho, C H; Bogie, K M
OBJECTIVE:To investigate the hypothesis that stereophotogrammetric wound size monitoring shows suitable inter-observer reliability and user acceptance for clinical practice use. METHOD/METHODS:Veterans admitted for conservative management of severe pressure ulcers were eligible for inclusion in the study. Three-dimensional (3D) digital wound images were independently captured by two expert and two non-expert nurse-observers using a commercially available stereophotogrammetry system,weekly for 6 weeks.A double-blinded analyst generated 3D wound reconstructions, using software to determine geometry. Clinical opinion of wound progression was provided by an expert physician. RESULTS:Thirteen wounds were assessed with more than 80% of all images being readable. Interclass correlation of 0.9867 (p < 0.000 I) was observed. Compared with clinical opinion, 3D wound measurement was sensitive between improving and static wounds for wound perimeter, volume, depth and length. CONCLUSION/CONCLUSIONS:These preliminary findings suggest that 3D wound measurement minimises differences in wound measurement between expert and non-expert observers, suggesting it could be implemented with high reliability in health-care settings where several observers are involved in wound care management.
PMID: 23665664
ISSN: 0969-0700
CID: 4552182