111 results on '"Johnson, Timothy P."'
Search Results
2. How influential is the role of oligotrophication on the integrity of fish assemblages in the littoral zone?
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Shimoda, Yuko, Cai, Haibin, Fernando, Yasasi, Okoli, Akunne, Xu, Zhuowei, Koops, Marten, Johnson, Timothy B., and Arhonditsis, George B.
- Abstract
Food web theory predicts that one of the consequences of oligotrophication is the decline in fisheries following the establishment of nutrient-deficient conditions and low biogenic production. However, emerging evidence suggests that more complex trophic interactions, induced by plankton composition, dietary diversification, temporal and spatial heterogeneity, variations in fish age and size structure can lead to ecosystem responses that deviate from theoretical predictions; especially in the shallow littoral zone. In this study, two end-to-end modelling strategies are used to characterize potential food web structural shifts and overall ecosystem productivity in response to oligotrophication. Our modelling strategy draws upon empirical and theoretical evidence from the Bay of Quinte, a semi-enclosed embayment in northeastern Lake Ontario that has been subjected to phosphorus (P) abatement strategies in the 1970s. We first show that the role of food abundance has been a primary factor shaping fish production, but the fish community gradually responded to the reduced availability of pelagic staples of their diet by displaying greater reliance upon alternative sources, including benthic and other autochthonous (or even allochthonous) food items. Our analysis further suggests that degree of diet overlap between competing trophic guilds can significantly modulate realized biomass levels. The composition of the autotrophic community is another major confounding factor that can induce significant variations from the predicted food web productivity patterns in response to oligotrophication. Overall, our analysis suggests that the proposed reduction of the ambient total phosphorus levels may not necessarily trigger a significant decline in fish biomass in the Bay of Quinte. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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3. A venue analysis of predictors of alcohol use prior to sexual intercourse among female sex workers in Senggigi, Indonesia
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Safika, Iko, Johnson, Timothy P., and Levy, Judith A.
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- 2011
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4. Comparative trophic ecology of nearshore juvenile salmonids in Lake Ontario.
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Nawrocki, Brent M., Zhu, Changhai, and Johnson, Timothy B.
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The trophic ecology of juvenile salmonids in nearshore Lake Ontario is not well understood. We used stomach content and stable isotope diet and niche metrics, as well as condition metrics to understand the trophic ecology of juvenile Atlantic salmon (Salmo salar), brown trout (Salmo trutta), Chinook salmon (Oncorhynchus tshawytscha), coho salmon (Oncorhynchus kisutch), rainbow trout (Oncorhynchus mykiss), and lake trout (Salvelinus namaycush). Salmonids had comparable length-weight slopes and stomach mass, and allometric patterns existed between fork-length and both relative stomach content mass and energy density for all species. Interspecific differences existed with respect to diet, and the magnitude of difference generally increased with increasing body size. Small sized salmonid (fork length < 100 mm) diets mainly consisted of Diptera (% volume = 66 – 100; prey isotope %: 11.7 – 78.4), while large sized salmonids (fork length 200 – 300 mm) consumed fish (% volume = 20–100; prey isotope % = 21.5 – 42.7). Salmonids exhibited high interspecific niche overlap, with lake trout (SEA B = 22.9 ‰
2 ) and brown trout (18.6 ‰2 ) having the largest isotopic niche size, and Atlantic salmon having the smallest (2.7 ‰2 ). Our study addressed a knowledge gap in trophic ecology between mostly stream-dwelling juvenile and open lake adult salmonid life stages, revealing differences in diet but comparable condition metrics which suggests different strategies to optimise performance in the nearshore environment. [ABSTRACT FROM AUTHOR]- Published
- 2022
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5. Sexual victimization and hazardous drinking among heterosexual and sexual minority women
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Hughes, Tonda L., Szalacha, Laura A., Johnson, Timothy P., Kinnison, Kelly E., Wilsnack, Sharon C., and Cho, Young
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Sexual abuse ,Women ,Health ,Sociology and social work - Abstract
To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.addbeh.2010.07.004 Byline: Tonda L. Hughes, Laura A. Szalacha, Timothy P. Johnson, Kelly E. Kinnison, Sharon C. Wilsnack, Young Cho Keywords: Adult sexual assault; Childhood sexual abuse; Hazardous drinking; Revictimization; Sexual orientation Abbreviations: ASA, Adult Sexual Assault; CSA, Childhood Sexual Abuse; CHLEW, Chicago Health and Life Experiences of Women; NSHLEW, National Survey of Health and Life Experiences of Women Abstract: Although research shows that sexual minority women report high rates of lifetime sexual victimization and high rates of hazardous drinking, investigators have yet to explore the relationships between sexual victimization and hazardous drinking in this population. In addition, because the rates of these problems may vary within the sexual minority population, we examined and compared relationships between sexual victimization and hazardous drinking in exclusively heterosexual and sexual minority (mostly heterosexual, bisexual, mostly lesbian and exclusively lesbian) women.
- Published
- 2010
6. Prevalence of recent illicit substance use and reporting bias among MSM and other urban males
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Mackesy-Amiti, Mary Ellen, Fendrich, Michael, and Johnson, Timothy P.
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Substance abuse -- Social aspects ,Prevalence studies (Epidemiology) -- Social aspects ,Health ,Sociology and social work - Abstract
To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.addbeh.2008.03.003 Byline: Mary Ellen Mackesy-Amiti (a), Michael Fendrich (b), Timothy P. Johnson (c) Keywords: Substance use; MSM; Reporting bias Abstract: This paper explores whether elevated rates of self-reported substance use among MSM compared to other males may be an artifact of reporting bias. Past month prevalence rates of marijuana, cocaine, heroin, methamphetamine, Ecstasy, and Ketamine use were compared between a sample of men who have sex with men (MSM), and a general household sample of men, all residing in Chicago. We compared rates of self-reported use, and corrected rates based on the results of drug testing (urine and oral fluid tests). While MSM over 30 years old were significantly more likely than other men in this age group to report past month use of cocaine, test-corrected rates of use were equivalent. On the other hand, test-corrected estimates confirmed elevated rates of Ketamine and Ecstasy use in the MSM sample. Differential disclosure of substance use between MSM and other males may in some cases lead to distorted conclusions about differences in substance use between these groups. The use of biological testing in epidemiological studies of substance use can reduce the uncertainty of such comparisons. Author Affiliation: (a) Community Outreach Intervention Projects, School of Public Health, University of Illinois at Chicago, 1603 W. Taylor St., Chicago, IL 60612 USA (b) Center for Addiction and Behavioral Health Research, Helen Bader School of Social Welfare, University of Wisconsin-Milwaukee, 2400 E. Hartford Ave., Milwaukee WI 53211 USA (c) Survey Research Laboratory, College of Urban Planning and Public Administration, University of Illinois at Chicago, 412 S. Peoria St., Chicago IL 60607 USA
- Published
- 2008
7. Tobacco-reporting validity in an epidemiological drug-use survey
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Fendrich, Michael, Mackesy-Amiti, Mary Ellen, Johnson, Timothy P., Hubbell, Amy, and Wislar, Joseph S.
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Drug abuse -- Surveys ,Tobacco (Plant) -- Research ,Epidemiologic methods -- Usage ,Mandatory drug testing -- Methods ,Health ,Sociology and social work - Abstract
The estimation of tobacco-reporting validity in an epidemiological survey on drug use was carried out by comparing the responses to questions about tobacco use and passive exposure to smoking with biological tests for cotinine. The underreporting of tobacco was relatively rare but the estimates of the study state that it may be increasing over time.
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- 2005
8. Spatial and seasonal variability in trophic relationships and carbon sources of two key invertebrate species in Lake Ontario.
- Author
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Uzarski, Donald R., Fisk, Aaron T., Heuvel, Cecilia E., O'Malley, Brian P., Weidel, Brian C., Larocque, Sarah M., and Johnson, Timothy B.
- Abstract
Mysids (Mysis diluviana) and dreissenids (Dreissena polymorpha and mostly D. bugensis) are important invertebrate taxa in the food webs of the Laurentian Great Lakes but there are uncertainties about the seasonal and spatial variability in their stable isotope signatures. We quantified δ
13 C and δ15 N in 304 mysid and 366 dreissenid samples across five spatial ecoregions, varying site depth, and three seasons (spring, summer, and fall) in Lake Ontario in 2012 and 2013. Particulate organic matter (POM) was also collected across site depth and season from the Deep Hole ecoregion for use as an isotopic baseline. Lipid normalization models for δ13 C were generated for both taxa to reduce lipid bias in our statistical analysis. Season was a significant predictor of POM stable isotopes, with δ13 C lower in the summer and δ15 N decreasing from spring to summer before increasing into fall. Mysid lipid normalized δ13 C varied by site depth and ecoregion while δ15 N decreased across season and did not vary by site depth or ecoregion. Dreissenid stable isotopes varied significantly across season, depth, and ecoregion, with site depth having positive relationship with δ15 N. Mysids and dreissenids were two trophic positions higher than POM based on δ15 N; this comparison was restricted to the one region where POM was collected. Isotopic variability suggested selective feeding within POM and differing trophic pathways between mysids and dreissenids. Collecting an appropriate taxon across all observed variables to serve as an isotopic baseline, particularly in spatial and temporal studies, is critical to the correct interpretation of trophic relationships. [ABSTRACT FROM AUTHOR]- Published
- 2024
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9. Developing a short screener for acquiescent respondents.
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Lee, Sunghee, Alvarado-Leiton, Fernanda, Yu, Wenshan, Davis, Rachel, and Johnson, Timothy P.
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Background: Acquiescent response style (ARS) refers to survey respondents' tendency to choose response categories agreeing to questions regardless of their content and is hypothesized as a stable respondent trait. While what underlies acquiescence is debatable, the effect of ARS on measurement is clear: bias through artificially increased agreement ratings. With certain population subgroups (e.g., racial/ethnic minorities in the U.S.) are associated with systemically higher ARS, it causes concerns for research involving those groups. For this reason, it may be necessary to classify respondents as acquiescers or a nonacquiescers, which allows independent analysis or accounting for this stylistic artifact. However, this classification is challenging, because ARS is latent, observed only as a by-product of collected data.Objectives: To propose a screener that identifies respondents as acquiescers.Methods: With survey data collected for ARS research, various ARS classification methods were compared for validity as well as implementation practicality.Results: The majority of respondents was classified consistently into acquiescers or nonacquiescers under various classification methods.Conclusions: We propose a method based on illogical responses given to two balanced, theoretically distant multi-item measurement scales as a screener. [ABSTRACT FROM AUTHOR]- Published
- 2022
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10. Patterns in spatial use of land-locked Atlantic salmon (Salmo salar) in a large lake.
- Author
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Larocque, Sarah M., Lake, Colin, Johnson, Timothy B., and Fisk, Aaron T.
- Abstract
Understanding the spatial use of reintroduced fish is useful for fisheries management and evaluating restoration success. Atlantic salmon (Salmo salar) were reintroduced into Lake Ontario in the 1990s; however, the movement ecology of these land-locked fish is unknown. Using acoustic telemetry and Floy tag mark-recaptures, we examined seasonal home range and space use of Atlantic salmon in Lake Ontario. Hatchery-raised adult Atlantic salmon were tagged with acoustic transmitters (n = 14; 8 with depth sensors) or Floy tags (n = 1915) and released. Both acoustic telemetry and Floy tag recaptures (n = 90) indicated cross lake movements, and home ranges encompassed nearly the entire lake in summer but was smaller in winter. Movements were nearshore (<2 km from shore) from spring to summer at ∼20 m bathymetric depths, with movements closer to shore in the fall, and further offshore (∼5.5 km from shore and 45 m bathymetric depths) in winter. Depth use was relatively shallow (<4 m) with occasional deeper dives (max = 28.5 m), and small diel vertical movements (1–5 m), moving deeper during daytime, consistent with ocean movements of Atlantic salmon. There appears to be spatial segregation among Atlantic salmon and other Lake Ontario salmonids, however, overlap likely occurs in nearshore waters during the spring. Wide-ranging movements of Atlantic salmon in binational (Canada/USA) waters reflects the importance of government agencies collaborating to ensure sustainable fisheries and the coordination of species restoration activities. This is the first study to provide detailed spatial use of Lake Ontario Atlantic salmon to assist in the management of this reintroduced species. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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11. Results of the collaborative Lake Ontario bloater restoration stocking and assessment, 2012–2020.
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Weidel, Brian C., Ackiss, Amanda S., Chalupnicki, Marc A., Connerton, Michael J., Davis, Steve, Dettmers, John M., Drew, Timothy, Fisk, Aaron T., Gordon, Roger, Hanson, S. Dale, Holden, Jeremy P., Holey, Mark E., Johnson, James H., Johnson, Timothy B., Lake, Colin, Lantry, Brian F., Loftus, Kevin K., Mackey, Gregg E., McKenna, James E., and Millard, Michael J.
- Abstract
Bloater, Coregonus hoyi , are deepwater planktivores native to the Laurentian Great Lakes and Lake Nipigon. Interpretations of commercial fishery time series suggest they were common in Lake Ontario through the early 1900s but by the 1950s were no longer captured by commercial fishers. Annual bottom trawl surveys that began in 1978 and sampled extensively across putative bloater habitat only yielded one individual (1983), suggesting that the species had been locally extirpated. In 2012, a multiagency restoration program stocked bloater into Lake Ontario from gametes collected in Lake Michigan. From 2012 to 2020, 1,028,191 bloater were stocked into Lake Ontario. Bottom trawl surveys first detected stocked fish in 2015, and through 2020 ten bloater have been caught (total length mean = 129 mm, s.d. = 44 mm, range: 96–240 mm). Hatchery applied marks and genetic analyses confirmed the species identification and identified stocking location for some individuals. Trawl capture locations and acoustic telemetry suggested that stocked fish dispersed throughout the main lake within months or sooner, and the depth distribution of recaptured bloater was similar to historic distributions in Lake Ontario and other Great Lakes. Predicted bloater trawl catches, based on modeled population abundance and trawl survey efficiency, were similar to observed catches, suggesting that post-stocking survival is less than 20% and contemporary bottom trawl surveys can quantify bloater abundance at low densities and track restoration. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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12. Spatial and temporal variability in lake trout diets in Lake Ontario as revealed by stomach contents and stable isotopes.
- Author
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Nawrocki, Brent M., Metcalfe, Brent W., Holden, Jeremy P., Lantry, Brian F., and Johnson, Timothy B.
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Lake trout (Salvelinus namaycush) are an ecologically and economically important piscivore with reported differences in diet and feeding behaviour throughout its range. Eleven stomach content and stable isotope-based metrics were used to describe diets of 349 lake trout between two years (2013 and 2018) and among geographic zones (west, central, east, Kingston basin) in Lake Ontario. Using individual (e.g., volumetric, %V) and aggregate (e.g., index of relative importance, %IRI) diet metrics, we found an overwhelming dominance of alewife (Alosa pseudoharengus) in lake trout diets among some zones in 2013 (%V = 23.3 – 92.7; %IRI = 12.2 – 99.5) and all zones in 2018 (%V = 83.9 – 96.7; %IRI = 96.5 – 100). Round goby (Neogobius melanostomus) and rainbow smelt (Osmerus mordax) were secondary lake trout prey items with relative diet percentages only marginally reflected by spatial and temporal variation in prey abundance (round goby: %V = 1.0 – 33.3, %IRI = 0.1 – 13.2; rainbow smelt: %V = 2.5 – 54.0, %IRI = 0.1 – 54.0). Carbon (δ
13 C) and nitrogen (δ15 N) isotopic niche areas and orientations were similar across all year-zone combinations reinforcing temporal and spatial consistency in lake trout diet. The findings of this study advance the time series in describing Lake Ontario lake trout diets and can be used to complement stock assessments and management decisions associated with carrying capacity for the diverse salmonid community. [ABSTRACT FROM AUTHOR]- Published
- 2022
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13. Parametric Response Mapping of FLAIR MRI Provides an Early Indication of Progression Risk in Glioblastoma.
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Hoff, Benjamin A., Lemasson, Benjamin, Chenevert, Thomas L., Luker, Gary D., Tsien, Christina I., Amouzandeh, Ghoncheh, Johnson, Timothy D., and Ross, Brian D.
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Rationale and Objectives: Glioblastoma image evaluation utilizes Magnetic Resonance Imaging contrast-enhanced, T1-weighted, and noncontrast T2-weighted fluid-attenuated inversion recovery (FLAIR) acquisitions. Disease progression assessment relies on changes in tumor diameter, which correlate poorly with survival. To improve treatment monitoring in glioblastoma, we investigated serial voxel-wise comparison of anatomically-aligned FLAIR signal as an early predictor of GBM progression.Materials and Methods: We analyzed longitudinal normalized FLAIR images (rFLAIR) from 52 subjects using voxel-wise Parametric Response Mapping (PRM) to monitor volume fractions of increased (PRMrFLAIR+), decreased (PRMrFLAIR-), or unchanged (PRMrFLAIR0) rFLAIR intensity. We determined response by rFLAIR between pretreatment and 10 weeks posttreatment. Risk of disease progression in a subset of subjects (N = 26) with stable disease or partial response as defined by Response Assessment in Neuro-Oncology (RANO) criteria was assessed by PRMrFLAIR between weeks 10 and 20 and continuously until the PRMrFLAIR+ exceeded a defined threshold. RANO defined criteria were compared with PRM-derived outcomes for tumor progression detection.Results: Patient stratification for progression-free survival (PFS) and overall survival (OS) was achieved at week 10 using RANO criteria (PFS: p <0.0001; OS: p <0.0001), relative change in FLAIR-hyperintense volume (PFS: p = 0.0011; OS: p <0.0001), and PRMrFLAIR+ (PFS: p <0.01; OS: p <0.001). PRMrFLAIR+ also stratified responding patients' progression between weeks 10 and 20 (PFS: p <0.05; OS: p = 0.01) while changes in FLAIR-volume measurements were not predictive. As a continuous evaluation, PRMrFLAIR+ exceeding 10% stratified patients for PFA after 5.6 months (p<0.0001), while RANO criteria did not stratify patients until 15.4 months (p <0.0001).Conclusion: PRMrFLAIR may provide an early biomarker of disease progression in glioblastoma. [ABSTRACT FROM AUTHOR]- Published
- 2021
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14. Interviewer effects of self-reported substance use among homeless persons
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Johnson, Timothy P. and Parsons, Jennifer A.
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Homeless persons -- Psychological aspects ,Substance abuse -- Surveys ,Drug addicts -- Demographic aspects ,Health ,Sociology and social work - Abstract
A study of survey responses from homeless people in Illinois indicates more willingness to report drug abuse to a male interviewer. Race and age-related direct effects are also observed during the survey, with more homeless people responding to white and older interviewers. These results have implications for the practice of demographically linking respondents with interviewers of identical characteristics.
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- 1994
15. 760 TRANSGLUTAMINASE 2 IS ELEVATED IN CROHN'S DISEASE ASSOCIATED STRICTURES AND EXERTS PROFIBROTIC ACTIVITIES IN MYOFIBROBLASTS AND EXPERIMENTAL INTESTINAL FIBROSIS.
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Chandra, Jyotsna, Czarnecki, Doug, Mukherjee, Pranab K., Mao, Ren, Bergin, Marianne, Huang, Linghong, Johnson, Timothy S., West, Gail A., Kessler, Sean, Fiocchi, Claudio, De La Motte, Carol, and Rieder, Florian
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- 2024
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16. Predicted growth of lake trout and Chinook salmon in a warming lake.
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Ivanova, Silviya V., Fisk, Aaron T., and Johnson, Timothy B.
- Abstract
Warming water temperatures present challenges for ectotherms in freshwater ecosystems through influence on metabolic rate and bioenergetics. Diet, such as the inclusion of high energy prey, can reduce these influences, but accurate temperature profiles are key to improved predictions. Here, using the Wisconsin bioenergetics approach, we modelled lake trout (Salvelinus namaycush) and Chinook salmon (Oncorhynchus tshawytscha) growth for two time periods (present [2010–2019] and future 30-year (2041–2070) averaged scenarios) in Lake Ontario with in-situ observed year-round temperatures (obtained through acoustic telemetry and pop-off data storage tags deployed between 2016 and 2019) occupied by the species. For the future, we considered two water temperature scenarios (low and high, where experienced temperature increased by a mean of 0.4 °C and 1.0 °C, respectively) and the effects of a hypothetical diet switch with the inclusion of higher energy prey (bloater, Coregonus hoyi) currently being reintroduced. Under all forecasted warming conditions, lake trout performed well and growth was 41.3 to 82.5 % above present when bloater was re-incorporated in the diet up to 40 %. Chinook salmon maximum attainable growth declined between 11.2 and 29.6 % under forecasted warming scenarios without diet change. However, when bloater comprised ∼ 33 % of their diet, Chinook salmon growth increased 3.7 % under the low future scenario compared to present. These results demonstrate that impacts of future lake warming on predatory fish will vary with life-history characteristics of species and composition and abundance of prey base, and highlights the need for effective management that diversifies and conserves forage fish species in the Great Lakes. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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17. Feasibility of implementing an integrated long-term database to advance ecosystem-based management in the Laurentian Great Lakes basin.
- Author
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Budnik, Richard R., Frank, Kenneth T., Collis, Lyndsie M., Fraker, Michael E., Mason, Lacey A., Muir, Andrew M., Pothoven, Steven A., Clapp, David F., Collingsworth, Paris D., Hoffman, Joel C., Hood, James M., Johnson, Timothy B., Koops, Marten A., Rudstam, Lars G., and Ludsin, Stuart A.
- Abstract
The North American Great Lakes have been experiencing dramatic change during the past half-century, highlighting the need for holistic, ecosystem-based approaches to management. To assess interest in ecosystem-based management (EBM), including the value of a comprehensive public database that could serve as a repository for the numerous physical, chemical, and biological monitoring Great Lakes datasets that exist, a two-day workshop was organized, which was attended by 40+ Great Lakes researchers, managers, and stakeholders. While we learned during the workshop that EBM is not an explicit mission of many of the participating research, monitoring, and management agencies, most have been conducting research or monitoring activities that can support EBM. These contributions have ranged from single-resource (-sector) management to considering the ecosystem holistically in a decision-making framework. Workshop participants also identified impediments to implementing EBM, including: 1) high anticipated costs; 2) a lack of EBM success stories to garner agency buy-in; and 3) difficulty in establishing common objectives among groups with different mandates (e.g., water quality vs. fisheries production). We discussed as a group solutions to overcome these impediments, including construction of a comprehensive, research-ready database, a prototype of which was presented at the workshop. We collectively felt that such a database would offer a cost-effective means to support EBM approaches by facilitating research that could help identify useful ecosystem indicators and management targets and allow for management strategy evaluations that account for risk and uncertainty when contemplating future decision-making. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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18. A cluster of carbapenemase-producing Enterobacter cloacae complex ST171 at a tertiary care center demonstrating an ongoing regional threat.
- Author
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Pereira, Edwin C., Anacker, Melissa, Houseman, Jeana, Horn, Mary E., Johnson, Timothy J., Lynfield, Ruth, Vagnone, Paula Snippes, Witwer, Medora, and Kline, Susan
- Abstract
• We observed 5 inpatients with carbapenemase-producing Enterobacter cloacae complex. • Pulsed-field gel electrophoresis patterns for 2 patient isolates were identical. • These 2 patients were in the same intensive care unit room 13 days apart. • Whole genome sequencing showed that these 2 isolates were closely related. • All isolates matched the clonal lineage of the main circulating strain in the region. In Minnesota and North Dakota, a clonal strain of bla KPC-3 -producing Enterobacter cloacae complex has been reported with increasing frequency. Between July 2015 and February 2016, 13 carbapenem-resistant E. cloacae complex isolates were identified at our institution. Five bla KPC -positive isolates were identified by polymerase chain reaction and underwent pulsed-field gel electrophoresis and whole genome sequencing. Medical records of these patients were reviewed. All 5 case-isolates belonged to sequence type 171 and were bla KPC-3 -positive. Three pulsed-field gel electrophoresis patterns with >90% similarity were identified in the 5 case-isolates. We identified overlaps in time and location between case patients. Plasmid types and resistance genes were nearly identical between the isolates. Whole genome sequencing showed isolates A, B, and D to be closely related with <10 core single-nucleotide polymorphisms differences. Isolates C and E were also closely related to each other, but more distantly to A, B, and D; all belonged to the clonal lineage of the major circulating E. cloacae complex strain in Minnesota and North Dakota. Despite having overlapping hospital stays, isolates for patients C and D were not identical. Isolates A and D were nearly identical, indicating possible transmission during hospitalization. Transmission of the other isolates may have occurred elsewhere. This report highlights the importance of using both epidemiologic and molecular data to track the spread of carbapenemase-producers. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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19. Guidelines of care for the management of primary cutaneous melanoma.
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Swetter, Susan M., Tsao, Hensin, Bichakjian, Christopher K., Curiel-Lewandrowski, Clara, Elder, David E., Gershenwald, Jeffrey E., Guild, Valerie, Grant-Kels, Jane M., Halpern, Allan C., Johnson, Timothy M., Sober, Arthur J., Thompson, John A., Wisco, Oliver J., Wyatt, Samantha, Hu, Shasa, Lamina, Toyin, and Work Group
- Abstract
The incidence of primary cutaneous melanoma continues to increase each year. Melanoma accounts for the majority of skin cancer-related deaths, but treatment is usually curative following early detection of disease. In this American Academy of Dermatology clinical practice guideline, updated treatment recommendations are provided for patients with primary cutaneous melanoma (American Joint Committee on Cancer stages 0-IIC and pathologic stage III by virtue of a positive sentinel lymph node biopsy). Biopsy techniques for a lesion that is clinically suggestive of melanoma are reviewed, as are recommendations for the histopathologic interpretation of cutaneous melanoma. The use of laboratory, molecular, and imaging tests is examined in the initial work-up of patients with newly diagnosed melanoma and for follow-up of asymptomatic patients. With regard to treatment of primary cutaneous melanoma, recommendations for surgical margins and the concepts of staged excision (including Mohs micrographic surgery) and nonsurgical treatments for melanoma in situ, lentigo maligna type (including topical imiquimod and radiation therapy), are updated. The role of sentinel lymph node biopsy as a staging technique for cutaneous melanoma is described, with recommendations for its use in clinical practice. Finally, current data regarding pregnancy and melanoma, genetic testing for familial melanoma, and management of dermatologic toxicities related to novel targeted agents and immunotherapies for patients with advanced disease are summarized. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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20. Diet and trophic niche space and overlap of Lake Ontario salmonid species using stable isotopes and stomach contents.
- Author
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Mumby, James A., Larocque, Sarah M., Johnson, Timothy B., Stewart, Thomas J., Fitzsimons, John D., Weidel, Brian C., Walsh, Maureen G., Lantry, Jana R., Yuille, Michael J., and Fisk, Aaron T.
- Abstract
Abstract Lake Ontario supports a diversity of native and non-native salmonids which are managed largely through stocking practices. Ecological changes (e.g., invasive species) altering the food web structure accompanied with shifts in prey abundance, necessitate understanding the trophic niches of Lake Ontario salmonids to aid in management. The objectives of this study were to quantify salmonid (5 species) trophic niches and dietary proportions using stable isotope ratios (δ
13 C and δ15 N) of a large sample set (adult fish (>300 mm; n = 672) and key offshore prey (5 species, n = 2037)) collected across Lake Ontario in 2013. Estimates of prey based on stable isotope ratios were similar to stomach contents. Based on stable isotope ratios, non-native prey dominated salmonid diet; in particular alewife (Alosa pseudoharengus) constituted the majority (0.31 to 0.93) of all salmonid diets, and round goby (Neogobius melanostomus) contributed 0.26 and 0.19 of brown trout (Salmo trutta) and lake trout (Salvelinus namaycush) diets, respectively. Trophic niche overlap was high between all salmonids, except lake trout. The largest trophic niche overlap occurred between Chinook (Oncorhynchus tshawytscha), coho (Oncorhynchus kisutch), and Atlantic salmon (Salmo salar), and their reliance on alewife infers a strong pelagic foraging strategy. Lake, brown and rainbow (Oncorhynchus mykiss) trout had larger and/or more distinct trophic niches indicative of a more variable diet across individuals and utilizing different foraging strategies and/or habitats. Overall, Lake Ontario salmonids maintained a high reliance on alewife, and their potential for plasticity in diet provides important information to management regarding population sustainability. [ABSTRACT FROM AUTHOR]- Published
- 2018
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21. Comparison of thermal tolerance and standard metabolic rate of two Great Lakes invasive fish species.
- Author
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Drouillard, Ken G., Feary, David A., Sun, Xin, O'Neil, Jessica A., Leadley, Todd, and Johnson, Timothy B.
- Abstract
Round goby ( Neogobius melanostomus ) and western tubenose goby ( Proterorhinus semilunaris ) invaded the Laurentian Great Lakes at approximately the same time and area yet have shown substantial differences in their post-invasion success with more rapid establishment and development of much larger abundances of round goby populations throughout the invaded habitat. In this study, we compared differences in physiological performance (thermal tolerance and standard metabolic rate) between round and tubenose goby collected from the Huron-Erie corridor. Tubenose goby were observed to have lower thermal tolerance but exhibited similar standard metabolic rate across environmental temperatures compared to round goby. At temperatures exceeding 31 °C, tubenose goby demonstrated significantly higher mortalities and shorter times to death relative to round goby. The observed differences in thermal tolerance were consistent with differences in the native geographic ranges observed for each species at their southern ranges. The observed differences in physiological performance combined with species differences in other life history traits such body size, reproduction, feeding ecology and habitat affiliation may also explain differences in the invasiveness experienced by these two Great Lakes invasive fish including a greater ability of round gobies to occupy extreme habitats with large water temperature fluctuations. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
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22. Ethical issues in global health engagement.
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Kekulawala, Melani and Johnson, Timothy R.B.
- Abstract
With an increasing number of clinicians participating in global health work, such engagement is now more than ever in need of critical ethical scrutiny. Exemplary initiatives in research, academics and publication, and other special considerations, provide potential approaches for overcoming ethical challenges in global health work. These methods demonstrate that successful global health work includes a commitment to foundational ethical principles such as trust, honesty, open communication and transparency, sustainability, capacity building, and appreciation for multiple perspectives - principles that surpass the traditional considerations of clinical practice. From this perspective, successful interventions to reduce neonatal and perinatal mortality must be strategically focused on building in-country capacity and sustainability. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
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23. Bioenergetics modelling of grass carp: Estimated individual consumption and population impacts in Great Lakes wetlands.
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van der Lee, Adam S., Johnson, Timothy B., and Koops, Marten A.
- Abstract
Grass carp ( Ctenopharyngodon idella ), native to eastern Asia, have established populations throughout the Mississippi River basin and are now reproducing naturally in the Great Lakes basin. As a large herbivorous fish, there is concern that an established grass carp population in the Great Lakes may threaten nearshore vegetated areas and wetlands. We parameterized a bioenergetics model for grass carp from the primary literature to quantify individual consumption levels and estimate the impacts of an established population on macrophytes in representative areas of Lakes Erie and Ontario. Individual life time consumption was estimated under average, cool and warm temperature conditions. Under average temperature conditions, a population of grass carp could consume up to 27.6 kg of vegetation per kg of fish per year, depending on energy density of the vegetation. When consumption was estimated for populations of various grass carp biomass densities, most simulated scenarios resulted in < 50% of vegetation remaining in an invaded wetland after one year, with the majority of consumption from pre-adult stages. Direct impacts will likely exceed these effects due to losses to vegetation production potential from grass carp feeding early in the growing season and grass carp foraging activity resulting in plant damage or uprooting. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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24. A randomized clinical trial of a culturally responsive intervention for African American women with asthma.
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Patel, Minal R., Song, Peter X.K., Sanders, Georgiana, Nelson, Belinda, Kaltsas, Elena, Thomas, Lara J., Janevic, Mary R., Hafeez, Kausar, Wang, Wen, Wilkin, Margaret, Johnson, Timothy R., and Brown, Randall W.
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- 2017
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25. Estimates of lake trout (Salvelinus namaycush) diet in Lake Ontario using two and three isotope mixing models.
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Colborne, Scott F., Rush, Scott A., Paterson, Gordon, Johnson, Timothy B., Lantry, Brian F., and Fisk, Aaron T.
- Abstract
Recent development of multi-dimensional stable isotope models for estimating both foraging patterns and niches have presented the analytical tools to further assess the food webs of freshwater populations. One approach to refine predictions from these analyses is to include a third isotope to the more common two-isotope carbon and nitrogen mixing models to increase the power to resolve different prey sources. We compared predictions made with two-isotope carbon and nitrogen mixing models and three-isotope models that also included sulphur ( δ 34 S) for the diets of Lake Ontario lake trout ( Salvelinus namaycush ). We determined the isotopic compositions of lake trout and potential prey fishes sampled from Lake Ontario and then used quantitative estimates of resource use generated by two- and three-isotope Bayesian mixing models (SIAR) to infer feeding patterns of lake trout. Both two- and three-isotope models indicated that alewife ( Alosa pseudoharengus ) and round goby ( Neogobius melanostomus ) were the primary prey items, but the three-isotope models were more consistent with recent measures of prey fish abundances and lake trout diets. The lake trout sampled directly from the hatcheries had isotopic compositions derived from the hatchery food which were distinctively different from those derived from the natural prey sources. Those hatchery signals were retained for months after release, raising the possibility to distinguish hatchery-reared yearlings and similarly sized naturally reproduced lake trout based on isotopic compositions. Addition of a third-isotope resulted in mixing model results that confirmed round goby have become an important component of lake trout diet and may be overtaking alewife as a prey resource. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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26. Research needs to better understand Lake Ontario ecosystem function: A workshop summary.
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Stewart, Thomas J., Rudstam, Lars, Watkins, James, Johnson, Timothy B., Weidel, Brian, and Koops, Marten A.
- Abstract
Lake Ontario investigators discussed and interpreted published and unpublished information during two workshops to assess our current understanding of Lake Ontario ecosystem function and to identify research needs to guide future research and monitoring activities. The purpose of this commentary is to summarize key investigative themes and hypotheses that emerged from the workshops. The outcomes of the workshop discussions are organized under four themes: spatial linkages and interactions, drivers of primary production, trophic transfer, and human interactions. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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27. Intubations in elderly patients have decreased from 1999 through 2014-Results of a multi-center cohort study.
- Author
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Johnson, Timothy, Richman, Peter, Allegra, John R., Eskin, Barnet, and Seger, James
- Abstract
Background: Advances in pharmacologic therapy, non-invasive positive pressure ventilation (NIPPV) and advanced directives may have decreased the intubations of dyspneic elderly (≥65years old) patients in the emergency department (ED).Objective: To determine if the percentage of elderly ED patients intubated has decreased in recent years.Methods: Design: Retrospective multihospital cohort.Setting: Consecutive ED patients in nine NJ hospitals (1/1/1999 to 9/30/2014).Protocol: We identified patients intubated in the ED by CPT codes.Data Analysis: We calculated the annual percentage of patients ≥65 intubated and the percentage intubated by diagnosis along with 95% confidence intervals (CIs).Results: Of the 5,693,380 total patients in the database there were 1,065,371 visits for patients≥65. Their average age was 80±8years; 54% were female. Of these, 6297 were intubated (0.59%). From 1999 to 2014 the percent intubated decreased from 0.73% to 0.52%, a relative decrease of 29% (95% CI: 17%, 38%). The specific diagnoses with >500 intubations were congestive heart failure (CHF), pneumonia and cardiac arrest, accounting for 37% of the total. Of these three, CHF was the only diagnosis with a statistically significant change from 1999 to 2014: a relative decrease of 70% (95% CI: 53%, 81%). If all diagnoses without CHF are analyzed the overall relative decrease is 14% (95% CI: 3%, 24%).Conclusion: Intubation rates for patients≥65 decreased from 1999 through 2014, particularly in CHF patients. We speculate that these findings reflect wider implementation of NIPPV, other therapeutic modalities and advanced directives. [ABSTRACT FROM AUTHOR]- Published
- 2018
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28. Evaluation of Lake Ontario salmonid niche space overlap using stable isotopes.
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Yuille, Michael J., Fisk, Aaron T., Stewart, Tom, and Johnson, Timothy B.
- Abstract
The Lake Ontario ecosystem has undergone substantial ecological change over the past five decades. In this time, an economically important sport fishery developed around non-native salmon and trout species (i.e., Chinook and coho salmon ( Oncorhynchus tshawytscha and Oncorhynchus kisutch ) and rainbow trout ( Oncorhynchus mykiss )). While trying to maintain this economically important recreational fishery, fishery managers are also trying to restore native species to the ecosystem (i.e., lake trout ( Salvelinus namaycush ) and Atlantic salmon ( Salmo salar )). We describe the trophic niche space of five ecologically and socioeconomically important Lake Ontario salmonid species (Chinook and coho salmon and rainbow, brown ( Salmo trutta ) and lake trout) using stable isotopes of carbon and nitrogen ( 13 C and 15 N, respectively). Using a modified standard ellipse analysis, we found a high degree of stable isotope niche space overlap in Lake Ontario salmonid species. Lake trout had the largest trophic niche space and the smallest proportion of overlap relative to the other four salmonid species (14%–28%), whereas coho salmon had the smallest stable isotope niche space and exhibited the highest degree of overlap with the other species (66%–99%). This study identifies and quantifies dietary resource sharing between Lake Ontario salmonids and highlights the importance of other prey fish species to the restoration and sustainability of Lake Ontario salmonid fish stocks. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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29. Influence of habitat heterogeneity on the foraging ecology of first feeding yellow perch larvae, Perea flavescens, in western Lake Erie.
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Marin Jarrin, Jose R., Pangle, Kevin L., Reichert, Julie M., Johnson, Timothy B., Tyson, Jeff, and Ludsin, Stuart A.
- Abstract
The diet of first-feeding fish larvae can influence their future growth and survival. The foraging ecology of yellow perch (YP) larvae was studied in western Lake Erie, a region characterized by habitat heterogeneity associated with the Maumee River Plume (MRP) and a high prevalence of invasive species. To determine the influence of the MRP on YP diet, water physical characteristics, zooplankton prey community, and larval YP diet and foraging selectivity were compared between MRP and non-MRP waters, 2006-2008. Water temperature was higher, while water clarity was lower in the MRP when compared to non-MRP waters. The zooplankton prey community (groups constituting >1% ofYP prey items) did not differ between MRP and non-MRP waters, being composed of small cladocerans, cyclopoid and calanoid copepods and non-native dreissenid mussel veligers. Ration increased with YP total length (TL), with no differences found between MRP and non-MRP waters. Diet composition also varied with larval YP length, with the smallest larvae preying more heavily on dreissenid veligers than larger fish, and no differences between MRP and non-MRP waters. Most sizes of larvae positively selected for cyclopoid copepods in MRP and non-MRP waters, while selection for other prey was neutral or negative. Our study reveals a similar zooplankton community and larval foraging ecology between MRP and non-MRP waters during spring season, despite habitat physical differences, and points to mechanisms unassociated with larval foraging (i.e., predation) as a reason for higher recruitment of YP residing inside versus outside of the MRP as larvae. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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30. Parametric response mapping monitors temporal changes on lung CT scans in the subpopulations and intermediate outcome measures in COPD Study (SPIROMICS).
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Boes, Jennifer L., Hoff, Benjamin A., Bule, Maria, Johnson, Timothy D., Rehemtulla, Alnawaz, Chamberlain, Ryan, Hoffman, Eric A., Kazerooni, Ella A., Martinez, Fernando J., Han, Meilan K., Ross, Brian D., and Galbán, Craig J.
- Abstract
Rationale and Objectives: The longitudinal relationship between regional air trapping and emphysema remains unexplored. We have sought to demonstrate the utility of parametric response mapping (PRM), a computed tomography (CT)-based biomarker, for monitoring regional disease progression in chronic obstructive pulmonary disease (COPD) patients, linking expiratory- and inspiratory-based CT metrics over time.Materials and Methods: Inspiratory and expiratory lung CT scans were acquired from 89 COPD subjects with varying Global Initiative for Chronic Obstructive Lung Disease (GOLD) status at 30 days (n = 13) or 1 year (n = 76) from baseline as part of the Subpopulations and Intermediate Outcome Measures in COPD Study (SPIROMICS) clinical trial. PRMs of CT data were used to quantify the relative volumes of normal parenchyma (PRM(Normal)), emphysema (PRM(Emph)), and functional small airways disease (PRM(fSAD)). PRM measurement variability was assessed using the 30-day interval data. Changes in PRM metrics over a 1-year period were correlated to pulmonary function (forced expiratory volume at 1 second [FEV1]). A theoretical model that simulates PRM changes from COPD was compared to experimental findings.Results: PRM metrics varied by ∼6.5% of total lung volume for PRM(Normal) and PRM(fSAD) and 1% for PRM(Emph) when testing 30-day repeatability. Over a 1-year interval, only PRM(Emph) in severe COPD subjects produced significant change (19%-21%). However, 11 of 76 subjects showed changes in PRM(fSAD) greater than variations observed from analysis of 30-day data. Mathematical model simulations agreed with experimental PRM results, suggesting fSAD is a transitional phase from normal parenchyma to emphysema.Conclusions: PRM of lung CT scans in COPD patients provides an opportunity to more precisely characterize underlying disease phenotypes, with the potential to monitor disease status and therapy response. [ABSTRACT FROM AUTHOR]- Published
- 2015
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31. Geochemical Monitoring Considerations for the FutureGen 2.0 Project.
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Amonette, James E., Johnson, Timothy A., Spencer, Clayton F., Zhong, Lirong, Szecsody, James E., and Vermeul, Vince R.
- Abstract
Geochemical monitoring is an essential component of a suite of monitoring technologies designed to evaluate CO 2 mass balance and detect possible loss of containment at the FutureGen 2.0 geologic sequestration site near Jacksonville, IL. This presentation gives an overview of the potential geochemical approaches and tracer technologies that were considered, and describes the evaluation process by which the most cost-effective and robust of these were selected for implementation. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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32. Recycling Suture Limbs from Knotless Suture Anchors for Arthroscopic Shoulder Stabilization.
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Johnson, Timothy S., DiPompeo, Christine M., Ismaeli, Zahra C., Porter, Polly A., Johnson, David C., and Nicholson, Shannon L.
- Abstract
Recurrent shoulder instability often leads to labral abnormality that requires surgical intervention that may require fixation with suture anchors. The proposed surgical technique allows the surgeon to achieve 2 points of fixation around the labrum and/or capsule with a single suture secured to the glenoid with a knotless anchor. Instead of cutting and discarding the residual suture limbs after anchor insertion, this technique uses the residual suture limbs of the knotless anchor for a second suture pass. This technique (1) creates a more cost- and time-efficient surgical procedure than using multiple single-loaded anchors or double-loaded anchors, (2) decreases the known risk of glenoid fracture from the stress riser at the implant tips of multi-anchor repairs by reducing the number of anchors required for stabilization, (3) decreases the surgical time compared with the use of double-loaded anchors through simpler suture management and less knot tying, (4) allows for the secure reapproximation of the labrum to the glenoid while offering a convenient option for capsulorrhaphy without the need to insert another anchor, and (5) yields more points of soft-tissue fixation with fewer anchors drilled into the glenoid. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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33. A space-time point process model for analyzing and predicting case patterns of diarrheal disease in northwestern Ecuador.
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Ahn, Jaeil, Johnson, Timothy D., Bhavnani, Darlene, Eisenberg, Joseph N.S., and Mukherjee, Bhramar
- Abstract
Highlights: [•] We model case-patterns under a serial case–control study of diarrheal disease. [•] Two-stage space-time model attempts to understand the role of spatially and temporally referenced covariates. [•] Prediction of the number of cases at unsampled communities at a future time. [•] The log Gaussian Cox process (LGCP) is used to model spatial clustering of point patterns. [•] More remote communities have fewer diarrheal cases after adjusting for population differences. [Copyright &y& Elsevier]
- Published
- 2014
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34. Relationships among primary tumor size, number of involved nodes, and survival for 8044 cases of Merkel cell carcinoma.
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Iyer, Jayasri G, Storer, Barry E, Paulson, Kelly G, Lemos, Bianca, Phillips, Jerri Linn, Bichakjian, Christopher K, Zeitouni, Nathalie, Gershenwald, Jeffrey E, Sondak, Vernon, Otley, Clark C, Yu, Siegrid S, Johnson, Timothy M, Liegeois, Nanette J, Byrd, David, Sober, Arthur, and Nghiem, Paul
- Abstract
Background: The effects of primary tumor size on nodal involvement and of number of involved nodes on survival have not, to our knowledge, been examined in a national database of Merkel cell carcinoma (MCC).Objective: We sought to analyze a retrospective cohort of patients with MCC from the largest US national database to assess the relationships between these clinical parameters and survival.Methods: A total of 8044 MCC cases in the National Cancer Data Base were analyzed.Results: There was a 14% risk of regional nodal involvement for 0.5-cm tumors that increased to 25% for 1.7-cm (median-sized) tumors and to more than 36% for tumors 6 cm or larger. The number of involved nodes was strongly predictive of survival (0 nodes, 76% 5-year relative survival; 1 node, 50%; 2 nodes, 47%; 3-5 nodes, 42%; and ≥6 nodes, 24%; P < .0001 for trend). Younger and/or male patients were more likely to undergo pathological nodal evaluation.Limitations: The National Cancer Data Base does not capture disease-specific survival. Hence, relative survival was calculated by comparing overall survival with age- and sex-matched US population data.Conclusion: Pathologic nodal evaluation should be considered even for patients with small primary MCC tumors. The number of involved nodes is strongly predictive of survival and may help improve prognostic accuracy and management. [ABSTRACT FROM AUTHOR]- Published
- 2014
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35. Response to putative round goby (Neogobius melanostomus) pheromones by centrarchid and percid fish species in the Laurentian Great Lakes.
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Ochs, Cory L., Laframboise, Alyson J., Green, Warren W., Basilious, Alfred, Johnson, Timothy B., and Zielinski, Barbara S.
- Abstract
Abstract: Pheromone trapping is an increasingly viable strategy to reduce invasive fish populations, largely due to the pheromones'' function of evoking behavioral responses among conspecifics. Prior to attempting such population control techniques, the pheromones must be identified and their possible influences on non-target species addressed. The round goby (Neogobius melanostomus) is a species invasive to the Great Lakes region, and negatively impacts the ecosystem by interfering with local fish populations. At least two 5β-reduced 3α-hydroxyl steroids released by reproductive N. melanostomus (11-O-ETIO and 11-O-ETIO-3s) evoke olfactory sensory responses from the olfactory epithelium of conspecifics, and water conditioned by reproductive males (containing these steroids) attracts female round gobies. In this study, we examined whether these putative pheromones, along with simultaneously-released 11-O-ETIO-17s, stimulate olfactory sensory responses from alternative fish species sharing the same ecosystem as N. melanostomus in the Great Lakes region. Rock bass (Ambloplites rupestris), bluegill sunfish (Lepomis macrochirus), pumpkinseed sunfish (Lepomis gibbosus), smallmouth bass (Micropterus dolomieu), and yellow perch (Perca flavescens) were the targets of an electro-olfactogram experiment designed to record responses to odors. When compared to round goby responses from previous studies, amino acids and the bile acid consistently elicited electro-olfactogram responses across all species, but only round gobies showed a response to the putative pheromones. This study supports the concept of conducting a pheromone trapping trial in the field without adversely affecting the olfactory responses of non-target fish in the area. [Copyright &y& Elsevier]
- Published
- 2013
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36. Hemimysis anomala in Lake Ontario food webs: Stable isotope analysis of nearshore communities.
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Yuille, Michael J., Johnson, Timothy B., Arnott, Shelley E., and Campbell, Linda M.
- Abstract
Abstract: Hemimysis anomala, a littoral freshwater mysid native to the Ponto-Caspian region, is the newest invader to the Laurentian Great Lakes basin. Discovered in 2006, they have since been found in all of the Great Lakes (except Lake Superior) and have the potential to offset the dietary energy sink caused by invasive dreissenid mussels (Dreissena bugensis and D. polymorpha) in the littoral zone. We evaluated nearshore food web structure at four sites along Lake Ontario''s north shore spanning a gradient of Hemimysis density to determine: 1) if dominant nearshore food web pathways change seasonally, and 2) whether fish are exhibiting a dietary shift towards consumption of Hemimysis. No Hemimysis were found in any of the 431 fish (alewife Alosa pseudoharengus, round goby Neogobius melanostomus, and yellow perch Perca flavescens) stomachs analysed. We used stable isotopes of carbon (
13 C) and nitrogen (15 N) collected from invertebrates and fish to characterise trophic linkages and fish dietary preference. Yellow perch and round goby exhibited significantly higher Δδ15 N at Bronte (high Hemimysis density) compared to Cobourg, Waupoos and the Bay of Quinte. Δδ13 C of alewife is more enriched at Bronte and is comparable to the Δδ13 C of Hemimysis. Our results suggest that Hemimysis are being incorporated into diets of round gobies, alewife and small yellow perch and their reliance on Hemimysis as a dietary component increases with Hemimysis density. As Hemimysis populations continue to establish and stabilize, fish may incorporate this species into their diets at a higher rate. [Copyright &y& Elsevier]- Published
- 2012
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37. Round goby predation on Hemimysis anomala.
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Fitzsimons, John D., Bowen, Kelly, Brousseau, Christine, Dalton, Alex, MacVeigh, Brydon, Johnson, Timothy B., and Yuille, Mike
- Abstract
Abstract: The invasive Ponto-Caspian mysid Hemimysis anomala (hereafter Hemimysis) was first observed in south-eastern Lake Ontario in May 2006. In Lake Ontario, Hemimysis is most abundant at nearshore habitats characterised by cobble–rubble substrate, which it shares with the round goby Neogobius melanostomus (hereafter goby). To better understand the interaction if any between gobies and Hemimysis, gobies were collected throughout the summer and fall periods at three shallow (<3m) nearshore locations representing eastern, central, and western Lake Ontario where Hemimysis are relatively abundant. Goby stomach contents were examined for evidence of Hemimysis and other prey. In addition, gobies were collected at two locations in southwestern Lake Ontario in shallow- (3m) and deep- (11m) water nearshore habitat where stomach contents were also used to characterise diet. Despite higher Hemimysis abundance nearshore, Hemimysis were not consumed by any gobies collected from shallow nearshore locations, and only found in three of 23 gobies collected at the deep site. Goby abundance and consumption of Hemimysis by gobies at the deep site were unrelated to Hemimysis abundance in traps. At all locations, gobies fed on soft-bodied invertebrates and dreissenids although dreissenids were the dominant prey among large (>74mm) gobies. We suspect that the ability of Hemimysis to avoid predation by gobies is the result of a combination of anti-predator behaviours such as an evasive startle response, reduced activity and depth dependent segregation in interstitial spaces during the day, and a feeding mode used by gobies that is poorly suited for an evasive species like Hemimysis. [Copyright &y& Elsevier]
- Published
- 2012
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38. Distribution, abundance and production of Hemimysis anomala in Lake Ontario.
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Taraborelli, Ana Carolina, Jakobi, Nina, Johnson, Timothy B., Bowen, Kelly, and Boscarino, Brent T.
- Abstract
Abstract: Hemimysis anomala is one of the latest macroinvertebrates to invade the Laurentian Great Lakes. Since first reported in 2006, Hemimysis have been confirmed in several locations within the Great Lakes basin. However, little is known about the seasonal and spatial variation in demographics and dynamics of Hemimysis populations. We used a standardised pier-based methodology to describe the distribution of Hemimysis at 29 locations around the shoreline of Lake Ontario in 2009. Samples were collected in spring, summer, and fall at most locations, and bi-weekly at one site (Bronte Creek) over a 12-month period in 2009. For each site, we estimated abundance by sex and size. The more temporally intensive sampling at Bronte Creek enabled us to estimate production. Hemimysis were found at 83% of the sites visited, with densities generally highest in the northwest and lower at the other sites. Production estimates (2.67–14.09mg dry weight·m
−2 ·d−1 ) were higher than that of other common zooplankton species in the Great Lakes. We provide important life history parameters that will help ecologists better understand the potential impacts of Hemimysis on Great Lakes ecosystems. [Copyright &y& Elsevier]- Published
- 2012
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39. Dermatoscopic vascular patterns in cutaneous Merkel cell carcinoma.
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Harting, Mandy S., Ludgate, Mathew W., Fullen, Douglas R., Johnson, Timothy M., and Bichakjian, Christopher K.
- Abstract
Background: Merkel cell carcinoma (MCC) is one of the most aggressive primary cutaneous malignancies. The clinical diagnosis of MCC is often delayed. Although the rarity of this skin cancer partially explains the low clinical suspicion by physicians, the absence of characteristic clinical features contributes to the delay in diagnosis. Dermatoscopy has proven a useful diagnostic tool in other cutaneous malignancies; however, the dermatoscopic features of cutaneous MCC are unknown. Objective: We performed dermatoscopy on 10 primary cutaneous MCC to describe the dermatoscopic features and correlate these findings with the histopathologic parameters. Methods: Consecutive patients with cutaneous MCC were identified and their tumors were evaluated under dermatoscopy. An 8-point MCC histopathology profile was recorded for each primary tumor in an attempt to correlate individual parameters with dermatoscopic features. Results: All 10 tumors showed an irregular vascular pattern under dermatoscopy and demonstrated milky-red areas/globules and numerous linear irregular vessels. No correlation was noted between dermatoscopic and histopathologic features. Limitations: The patients were from a single institution and tumors evaluated by a single dermatoscopic reviewer. Because of the rarity of this tumor, a small number of tumors were evaluated (10). Conclusion: MCC exhibits a variety of dermatoscopic vascular patterns, most commonly milky-red areas/globules, polymorphous vessels, and linear-irregular vessels. Although we found no specific dermatoscopic pattern for MCC in our series, the polymorphous vascular pattern was atypical and suggestive of a malignant process. Further studies should be done to investigate the potential correlation between dermatoscopic features and histopathologic parameters. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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40. Leukocyte transcriptome from chickens infected with avian pathogenic Escherichia coli identifies pathways associated with resistance.
- Author
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Sandford, Erin E., Orr, Megan, Shelby, Mandy, Li, Xianyao, Zhou, Huaijun, Johnson, Timothy J., Kariyawasam, Subhashinie, Liu, Peng, Nolan, Lisa K., and Lamont, Susan J.
- Subjects
LEUCOCYTES ,PATHOGENIC bacteria ,BIRD infections ,ESCHERICHIA coli diseases ,CHICKEN diseases ,MORTALITY ,GENE expression - Abstract
Abstract: Avian pathogenic Escherichia coli (APEC) causes colibacillosis, which is responsible for morbidity and mortality in chickens. Gene expression patterns have previously been demonstrated to differ between chicken populations that are resistant vs. susceptible to bacterial infection, but little is currently known about gene expression response to APEC. Increased understanding of gene expression patterns associated with resistance will facilitate genetic selection to increase resistance to APEC. Male broiler chicks were vaccinated at 2 weeks of age and challenged with APEC at 4 weeks of age. Peripheral blood leukocytes were collected at 1 and 5 day post-infection. Lesions on the liver, pericardium, and air sacs were used to assign a mild or severe pathology status to non-vaccinated, challenged chicks. Ten treatment groups were therefore generated with a priori factors of vaccination, challenge, day post-infection, and the a posteriori factor of pathology status. Global transcriptomic response was evaluated using the Agilent 44K chicken microarray. APEC infection resulted in more up-regulation than down-regulation of differentially expressed genes. Immune response and metabolic processes were enriched with differentially expressed genes. Although vaccination significantly reduced lesions in challenged bird, there was no detectable effect of vaccination on gene expression. This study investigated the transcriptomic differences in host responses associated with mild vs. severe pathology, in addition to the effects of vaccination and challenge, thus revealing genes and networks associated with response to APEC and providing a foundation for future studies on, and genetic selection for, genetic resistance to APEC. [Copyright &y& Elsevier]
- Published
- 2012
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41. Seasonal variation in mercury and food web biomagnification in Lake Ontario, Canada.
- Author
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Zhang, Liang, Campbell, Linda M., and Johnson, Timothy B.
- Subjects
MERCURY ,SPATIO-temporal variation ,FOOD chains ,BIOCONCENTRATION - Abstract
Seasonal variation in mercury (Hg) concentrations and food web structure was assessed for eastern Lake Ontario. Hg concentrations, measured in 6 species of invertebrates and 8 species of fishes, tended to be highest in the spring and lowest in the summer for most biota. Yellow perch (Perca flavescens) exhibited significant ontogenetic shifts in diet and Hg, although such patterns were not evident for other species. Food web structure, as indicated by stable isotope values (δ
15 N, δ13 C) was not static. Log-transformed Hg data were strongly and consistently correlated with δ15 N values for the whole food web in each of the three seasons (slopes, 0.17–0.24) and across the entire year (slope, 0.2). While significantly different between seasons, the regression slope values are still consistent with published global Hg biomagnification rates. Our results indicate that the assessment of Hg trends in Great Lakes must take into account seasonal patterns and time of sampling. [Copyright &y& Elsevier]- Published
- 2012
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42. Closed-form shear flow solution for box–girder bridges under torsion
- Author
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Dowell, Robert K. and Johnson, Timothy P.
- Subjects
- *
SHEAR flow , *BOX girder bridges , *TORSION , *STIFFNESS (Mechanics) , *STRENGTH of materials , *THICKNESS measurement , *ELASTICITY - Abstract
Abstract: To provide desired stiffness and strength in torsion, bridge superstructures are often constructed with a cross-section consisting of multiple cells which have thin walls relative to their overall dimensions and resist Saint–Venant torsion through shear flow (force per unit length) that develops around the cell walls. For a single thin-walled cell subject to torsion, shear flow is constant along each of its walls while shear stresses vary around the section based upon changes in wall thickness. When the cross-section contains multiple cells they all contribute resistance to applied torsion and for elastic continuity each cell must twist the same amount. With these considerations, equilibrium and compatibility conditions allow simultaneous equations to be formed and solved to determine the shear flow for each cell. A second approach is a relaxation method that distributes incremental shear flows back and forth between cells, reducing errors with each distribution cycle, until the final shear flows for all cells approximate the correct values. A major advantage to this method is that it does not require setting up and solving simultaneous equations, favoring situations where hand calculation is desired. In this paper, a closed-form approach is introduced to determine, exactly, both the torsional constant and all shear flows for multi-cell cross-sections under torsion; no simultaneous equations are required and there is no need to distribute shear flows back and forth between cells. Simple closed-form equations are derived which give shear flows for cross-sections with any number of cells of arbitrary shape. [Copyright &y& Elsevier]
- Published
- 2012
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- View/download PDF
43. Shear and bending flexibility in closed-form moment solutions for continuous beams and bridge structures
- Author
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Dowell, Robert K. and Johnson, Timothy P.
- Subjects
- *
CONTINUOUS bridges , *SHEAR (Mechanics) , *STRUCTURAL engineering , *BENDING (Metalwork) , *STIFFNESS (Engineering) , *SIMULTANEOUS equations , *FLEXURE - Abstract
Abstract: Shear deformations can affect final member-end-moments for statically indeterminate continuous beams and frame structures, though for typical civil engineering structures their effect is small and moments can be based on flexural deformations only. When a member is deep relative to span length, however, shear deformations should be considered in the analysis. This can be included in the stiffness method and in a modified form of moment distribution where the carry-over factor is less than one-half due to the added flexibility from shear. In a prior paper the first author presented a new approach for solving statically indeterminate beams and bridge frames, with final end moments given in closed-form expressions. The advantages of this new approach are that no simultaneous equations are required as in the stiffness method, moments are not distributed back and forth as in moment distribution, and manual calculations may be used which give exact results for as many spans as desired. While only flexural deformations were considered in the original paper, this paper presents a closed-form approach that has been modified to include shear deformations. Final expressions are given for continuous beams and bridge frames, providing exact member-end-moments that match results from the stiffness method when shear deformations are included in the analysis. [Copyright &y& Elsevier]
- Published
- 2011
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44. Guidelines of care for the management of primary cutaneous melanoma. American Academy of Dermatology.
- Author
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Bichakjian CK, Halpern AC, Johnson TM, Foote Hood A, Grichnik JM, Swetter SM, Tsao H, Barbosa VH, Chuang TY, Duvic M, Ho VC, Sober AJ, Beutner KR, Bhushan R, Smith Begolka W, Bichakjian, Christopher K, Halpern, Allan C, Johnson, Timothy M, Foote Hood, Antoinette, and Grichnik, James M
- Abstract
The incidence of primary cutaneous melanoma has been increasing dramatically for several decades. Melanoma accounts for the majority of skin cancer-related deaths, but treatment is nearly always curative with early detection of disease. In this update of the guidelines of care, we will discuss the treatment of patients with primary cutaneous melanoma. We will discuss biopsy techniques of a lesion clinically suspicious for melanoma and offer recommendations for the histopathologic interpretation of cutaneous melanoma. We will offer recommendations for the use of laboratory and imaging tests in the initial workup of patients with newly diagnosed melanoma and for follow-up of asymptomatic patients. With regard to treatment of primary cutaneous melanoma, we will provide recommendations for surgical margins and briefly discuss nonsurgical treatments. Finally, we will discuss the value and limitations of sentinel lymph node biopsy and offer recommendations for its use in patients with primary cutaneous melanoma. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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45. Polymethylene-interrupted fatty acids: Biomarkers for native and exotic mussels in the Laurentian Great Lakes.
- Author
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Mezek, Tadej, Sverko, Ed, Rudy, Martina D., Zaruk, Donna, Capretta, Alfredo, Hebert, Craig E., Fisk, Aaron T., McGoldrick, Daryl J., Newton, Teresa J., Sutton, Trent M., Koops, Marten A., Muir, Andrew M., Johnson, Timothy B., Ebener, Mark P., and Arts, Michael T.
- Abstract
Abstract: Freshwater organisms synthesize a wide variety of fatty acids (FAs); however, the ability to synthesize and/or subsequently modify a particular FA is not universal, making it possible to use certain FAs as biomarkers. Herein we document the occurrence of unusual FAs (polymethylene-interrupted fatty acids; PMI-FAs) in select freshwater organisms in the Laurentian Great Lakes. We did not detect PMI-FAs in: (a) natural seston from Lake Erie and Hamilton Harbor (Lake Ontario), (b) various species of laboratory-cultured algae including a green alga (Scenedesmus obliquus), two cyanobacteria (Aphanizomenon flos-aquae and Synechococystis sp.), two diatoms (Asterionella formosa, Diatoma elongatum) and a chrysophyte (Dinobryon cylindricum) or, (c) zooplankton (Daphnia spp., calanoid or cyclopoid copepods) from Lake Ontario, suggesting that PMI-FAs are not substantively incorporated into consumers at the phytoplankton–zooplankton interface. However, these unusual FAs comprised 4–6% of total fatty acids (on a dry tissue weight basis) of native fat mucket (Lampsilis siliquoidea) and plain pocketbook (L. cardium) mussels and in invasive zebra (Dreissena polymorpha) and quagga (D. bugensis) mussels. We were able to clearly partition Great Lakes'' mussels into three separate groups (zebra, quagga, and native mussels) based solely on their PMI-FA profiles. We also provide evidence for the trophic transfer of PMI-FAs from mussels to various fishes in Lakes Ontario and Michigan, further underlining the potential usefulness of PMI-FAs for tracking the dietary contribution of mollusks in food web and contaminant-fate studies. [Copyright &y& Elsevier]
- Published
- 2011
- Full Text
- View/download PDF
46. A new American Joint Committee on Cancer staging system for cutaneous squamous cell carcinoma: Creation and rationale for inclusion of tumor (T) characteristics.
- Author
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Farasat, Sharifeh, Yu, Siegrid S., Neel, Victor A., Nehal, Kishwer S., Lardaro, Thomas, Mihm, Martin C., Byrd, David R., Balch, Charles M., Califano, Joseph A., Chuang, Alice Y., Sharfman, William H., Shah, Jatin P., Nghiem, Paul, Otley, Clark C., Tufaro, Anthony P., Johnson, Timothy M., Sober, Arthur J., and Liégeois, Nanette J.
- Abstract
Background: The incidence of cutaneous squamous cell carcinoma (cSCC) is increasing. Although most patients achieve complete remission with surgical treatment, those with advanced disease have a poor prognosis. The American Joint Committee on Cancer (AJCC) is responsible for the staging criteria for all cancers. For the past 20 years, the AJCC cancer staging manual has grouped all nonmelanoma skin cancers, including cSCC, together for the purposes of staging. However, based on new evidence, the AJCC has determined that cSCC should have a separate staging system in the 7th edition AJCC staging manual. Objective: We sought to present the rationale for and characteristics of the new AJCC staging system specific to cSCC tumor characteristics (T). Methods: The Nonmelanoma Skin Cancer Task Force of AJCC reviewed relevant data and reached expert consensus in creating the 7th edition AJCC staging system for cSCC. Emphasis was placed on prospectively accumulated data and multivariate analyses. Concordance with head and neck cancer staging system was also achieved. Results: A new AJCC cSCC T classification is presented. The T classification is determined by tumor diameter, invasion into cranial bone, and high-risk features, including anatomic location, tumor thickness and level, differentiation, and perineural invasion. Limitations: The data available for analysis are still suboptimal, with limited prospective outcomes trials and few multivariate analyses. Conclusions: The new AJCC staging system for cSCC incorporates tumor-specific (T) staging features and will encourage coordinated, consistent collection of data that will be the basis of improved prognostic systems in the future. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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47. Accuracy of Intra-Articular Glenohumeral Injections: The Anterosuperior Technique With Arthroscopic Documentation.
- Author
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Johnson, Timothy S., Mesfin, Addisu, Farmer, Kevin W., McGuigan, Lawrence A., Alamo, Ines G., Jones, Lynne C., and Johnson, David C.
- Abstract
Purpose: Our objective was to assess the accuracy rate of needle placement with the anterosuperior technique of glenohumeral joint injection that uses familiar palpable superficial landmarks as a guide instead of diagnostic imaging. Methods: Between April 2007 and October 2007 at our institution, 42 patients met the study inclusion criteria of being aged 18 years or older and undergoing shoulder arthroscopy. For the injection (performed by 1 surgeon), anesthetized patients were placed in the beach-chair position with the arm in adduction and internal rotation. The surgeon was allowed to redirect the needle only once without withdrawing the needle from the entry site. After injection, arthroscopic confirmation of needle position in the joint and the presence of backflow from the posterior portal cannula were used to determine accuracy and the relation of the needle to adjacent anatomy. Results: Of the 42 injections, 38 needles were inserted accurately into the glenohumeral joint (91% accuracy rate), most through the rotator interval (21) or the long head of the biceps tendon (9). Four needles were placed inaccurately into the anterior synovium and subacromial space. Adhesive capsulitis was the diagnosis in 3 of those 4 shoulders but in only 5 of the 38 shoulders in the group with accurate placement (P < .05). Body mass index was not statistically different between the accurate and inaccurate injection groups (P > .05). Conclusions: Anterosuperior glenohumeral joint injection without image guidance provides an accuracy rate of 91%. The anterosuperior technique for glenohumeral injections yields an accuracy rate higher than that of the standard anterior techniques and comparable to that of posterior injection. Level of Evidence: Level IV, diagnostic study. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
48. Round goby (Neogobius melanostomus) population structure, biomass, prey consumption and mortality from predation in the Bay of Quinte, Lake Ontario.
- Author
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Taraborelli, Ana Carolina, Fox, Michael G., Johnson, Timothy B., and Schaner, Ted
- Abstract
Abstract: We compared round goby (Neogobius melanostomus) population structure and biomass, estimated the quantity of prey consumed by round goby and assessed predation on round goby in two areas of the Bay of Quinte (upper and lower bay) that were invaded by this species two years apart. A bioenergetics approach was used to estimate round goby consumption and to illustrate the influence of changes in the round goby biomass, from May to October in both areas of the bay. Mean round goby biomass was 5tonnes/km
2 for the upper bay and 11.2tonnes/km2 for the lower bay. Round goby populations were dominated by age-0 to age-2 individuals; older individuals were rare although they constituted a greater portion of total biomass in the earlier invaded lower bay than the upper bay. Estimated round goby consumption was 78.4tonnes/km2 for the upper bay and 127.1tonnes/km2 for the lower bay; dreissenids were the most important prey followed by chironomids, zooplankton and amphipods. Diet analysis showed that round gobies were consumed by all predator species analyzed, and constituted a high percentage of stomach content biomass in yellow perch (Perca flavescens), largemouth bass (Micropterus salmoides) and northern pike (Esox lucius). Age structure differences between the upper and lower bay are consistent with those expected between expanding and stable populations. [ABSTRACT FROM AUTHOR]- Published
- 2010
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- View/download PDF
49. Pathologic nodal evaluation improves prognostic accuracy in Merkel cell carcinoma: Analysis of 5823 cases as the basis of the first consensus staging system.
- Author
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Lemos, Bianca D., Storer, Barry E., Iyer, Jayasri G., Phillips, Jerri Linn, Bichakjian, Christopher K., Fang, L. Christine, Johnson, Timothy M., Liegeois-Kwon, Nanette J., Otley, Clark C., Paulson, Kelly G., Ross, Merrick I., Yu, Siegrid S., Zeitouni, Nathalie C., Byrd, David R., Sondak, Vernon K., Gershenwald, Jeffrey E., Sober, Arthur J., and Nghiem, Paul
- Abstract
Background: The management of Merkel cell carcinoma (MCC) has been complicated by a lack of detailed prognostic data and by the presence of conflicting staging systems. Objective: We sought to determine the prognostic significance of tumor size, clinical versus pathologic nodal evaluation, and extent of disease at presentation and thereby derive the first consensus staging/prognostic system for MCC. Methods: A total of 5823 prospectively enrolled MCC cases from the National Cancer Data Base had follow-up data (median 64 months) and were used for prognostic analyses. Results: At 5 years, overall survival was 40% and relative survival (compared with age- and sex-matched population data) was 54%. Among all MCC cases, 66% presented with local, 27% with nodal, and 7% with distant metastatic disease. For cases presenting with local disease only, smaller tumor size was associated with better survival (stage I, ≤2 cm, 66% relative survival at 5 years; stage II, >2 cm, 51%; P < .0001). Patients with clinically local-only disease and pathologically proven negative nodes had better outcome (76% at 5 years) than those who only underwent clinical nodal evaluation (59%, P < .0001). Limitations: The National Cancer Data Base does not capture disease-specific survival. Overall survival for patients with MCC was therefore used to calculate relative survival based on matched population data. Conclusion: Although the majority (68%) of patients with MCC in this nationwide cohort did not undergo pathologic nodal evaluation, this procedure may be indicated in many cases as it improves prognostic accuracy and has important treatment implications for those found to have microscopic nodal involvement. [ABSTRACT FROM AUTHOR]
- Published
- 2010
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50. Affinity Peptide for Targeted Detection of Dysplasia in Barrett's Esophagus.
- Author
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Li, Meng, Anastassiades, Constantinos P., Joshi, Bishnu, Komarck, Chris M., Piraka, Cyrus, Elmunzer, Badih J., Turgeon, Danielle K., Johnson, Timothy D., Appelman, Henry, Beer, David G., and Wang, Thomas D.
- Subjects
DYSPLASIA ,BARRETT'S esophagus ,PEPTIDES ,MOLECULAR probes ,ENZYME-linked immunosorbent assay ,FLUORESCENCE microscopy ,FLOW cytometry ,EARLY diagnosis ,DIAGNOSIS - Abstract
Background & Aims: Dysplasia is a premalignant condition in Barrett''s esophagus that is difficult to detect on endoscopy because of its flat architecture and patchy distribution. Peptides are promising for use as novel molecular probes that identify cell surface targets unique to disease and can be fluorescence-labeled for detection. We aim to select and validate an affinity peptide that binds to esophageal dysplasia for future clinical studies. Methods: Peptide selection was performed using phage display by removing nonspecific binders using Q-hTERT (intestinal metaplasia) cells and achieving specific binding against OE33 (esophageal adenocarcinoma) cells. Selective binding was confirmed on bound phage counts, enzyme-linked immunosorbent assay (ELISA), flow cytometry, competitive inhibition, and fluorescence microscopy. On stereomicroscopy, specific peptide binding to dysplasia on endoscopically resected specimens was assessed by rigorous registration of fluorescence intensity to histology in 1-mm intervals. Results: The peptide sequence SNFYMPL was selected and showed preferential binding to target cells. Reduced binding was observed on competition with unlabeled peptide in a dose-dependent manner, an affinity of K
d = 164 nmol/L was measured, and peptide binding to the surface of OE33 cells was validated on fluorescence microscopy. On esophageal specimens (n = 12), the fluorescence intensity (mean ± SEM) in 1-mm intervals classified histologically as squamous (n = 145), intestinal metaplasia (n = 83), dysplasia (n = 61), and gastric mucosa (n = 69) was 46.5±1.6, 62.3±5.8, 100.0±9.0, and 42.4 ± 3.0 arb units, respectively. Conclusions: The peptide sequence SNFYMPL binds specifically to dysplasia in Barrett''s esophagus and can be fluorescence labeled to target premalignant mucosa on imaging. [Copyright &y& Elsevier]- Published
- 2010
- Full Text
- View/download PDF
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