35 results on '"Dixon LR"'
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2. Prototypes in education and clinical practice. The University of California, San Diego Nurse-Midwifery Bridge Program: an opportunity to learn intrapartum nursing skills.
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Hunter LP, Dixon LR, and Lops VR
- Published
- 1997
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3. Identification and quantification of pigments in plant leaves using thin layer chromatography-Raman spectroscopy (TLC-Raman).
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Payne TD, Dixon LR, Schmidt FC, Blakeslee JJ, Bennett AE, and Schultz ZD
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- Chromatography, Thin Layer methods, Pigments, Biological analysis, Pigments, Biological chemistry, Plant Leaves chemistry, Spectrum Analysis, Raman methods, Carotenoids analysis, Carotenoids chemistry, Solanum lycopersicum chemistry, Solanum lycopersicum metabolism
- Abstract
Carotenoids are yellow, orange, and red pigments commonly found in plants. In leaves, these molecules are essential for photosynthesis, but they also play a major role in plant growth and development. Efficiently monitoring concentrations of specific carotenoids in plant tissues could help to explain plant responses to environmental stressors, infection and disease, fertilization, and other conditions. Previously, Raman methods have been used to demonstrate a correlation between plant fitness and the carotenoid content of leaves. Due to solvatochromatic effects and structural similarities within the carotenoid family, current Raman spectroscopy techniques struggle to assign signals to specific carotenoids with certainty, complicating the determination of amounts of individual carotenoids present in a sample. In this work, we use thin layer chromatography-Raman spectroscopy, or TLC-Raman, to identify and quantify carotenoids extracted from tomato leaves. These quick and accurate methods could be applied to study the relationship between pigment content and a number of factors affecting plant health.
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- 2024
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4. Experiential exposure as the key to recruiting medical students into pathology.
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Holloman AM, Berg MP, Bryant B, Dixon LR, George MR, Karp JK, Knollmann-Ritschel BE, Prieto VG, Timmons CF, Childs JM, Lofgreen A, Johnson K, and McCloskey CB
- Abstract
Medical student interest and pursuit of a career in pathology have been steadily declining since 2015. We conducted three separate surveys of medical students to better understand these trends. In our first survey, we focused on assessing U.S. allopathic medical students understanding and perceptions of pathology. We later surveyed U.S. osteopathic medical students as a companion to the allopathic medical student survey, in which many similarities were discovered with some key differences. In our final survey, we specifically looked at curriculum differences between the U.S. allopathic medical schools that graduate the most students who enter pathology training programs (Group 1) versus those schools that graduate the fewest future pathologists (Group 2) to determine if the curriculum had an impact on medical student matriculation into pathology. Together, through these surveys, we were able to identify several remarkable recurring trends, presenting areas of targetable action. Here, we summarize themes from the three studies as well as a review of pertinent literature to offer best practices for exposing and engaging medical students to pathology and possibly recruiting students to consider pathology as a career., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
- Published
- 2023
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5. How influential are medical school curriculum and other medical school characteristics in students' selecting pathology as a specialty?
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McCloskey CB, Brissette M, Childs JM, Lofgreen A, Johnson K, George MR, Holloman AM, Bryant B, Berg MP, Dixon LR, Karp JK, Knollmann-Ritschel BEC, Prieto VG, Timmons CF, and Hoffman RD
- Abstract
There has been a significant decline in the number of United States allopathic medical students matching to pathology residency programs. Data acquired from the American Association of Medical Colleges (AAMC) show sustained variation in the medical school production of students who go on to pathology residency. When divided into groups based on the medical school's historical volume of graduates entering pathology, the schools in groups labeled Group 1 and Group 2 produced significantly higher and lower proportions of pathology residents, respectively. This study aimed to identify what medical school curriculum elements and other medical school characteristics might explain the differences observed in the AAMC data. The Dean or another undergraduate medical education contact from the Group 1 and Group 2 schools was invited to participate in an interview. Pathology Program Directors and Pathology Department Chairs were also included in communications. Thirty interviews were completed with equal numbers from each group. Interview questions probed pathology experiences, existence, and structure of a pathology interest group, options for post-sophomore fellowships, recent curriculum changes, and the extent of mentoring programs. Surprisingly, the curriculum does not appear to be a predictor of a medical school's production of students who enter pathology residency. A significantly greater percentage of Group 1 schools are public institutions compared to Group 2 schools. Other factors that may increase the number of students who go into pathology include mentoring, active learning versus observation, and post-sophomore fellowships or other opportunities to work in the capacity of a new pathology resident., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© 2023 The Authors.)
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- 2023
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6. Grazing and topography control nutrient pools in low Arctic soils of Southwest Greenland.
- Author
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van Soest MAJ, Anderson NJ, Bol R, Dixon LR, and Haygarth PM
- Abstract
Soil nutrient pools in the dry low Arctic are likely to be released under climatic change and this bioavailability has the potential to increase both terrestrial and aquatic productions. As well as the direct effect of warming, external disturbances such as nutrient deposition and grazing can also drive ecosystem change. This study in the low Arctic Kangerlussuaq area of southwest Greenland compared soil nutrient pools in terms of both topographic position on a catena and by soil depth in two small catchments with contrasting muskox abundance. We tested the hypotheses that there were differences between soil carbon (C), nitrogen (N) and phosphorus (P) across a soil catena (ridge - slope - valley) and by soil depth (litter - 0-5 cm - 25-30 cm) for the two sites (SS17b, muskox present, versus - SS85, no muskox). Total C and N concentrations of soils were on average lower at SS17b compared to SS85. Moreover, the soil N concentration increased downslope in the catena with higher amounts in the valleys compared to the slopes and ridges. Soil P concentration (0.70 g P kg
-1 ) was similar between catchments; however, litter P content was substantially different. The difference in soil nutrients between the two catchments was most likely due to the presence of muskox at SS17b, and hence grazing associated processes (defecation, altered microbiology and nutrient cycling). This study emphasises the heterogeneity of arctic landscapes and need for ecosystem specific research., Highlights: Soil nutrient pools in two low-arctic catchments in Greenland were compared.Grazing and dung inputs by muskox affect soil nutrient pools in Greenland.Soil P stores in Kangerlussuaq are similar to intensively managed farmland in Europe.The heterogeneity of arctic landscapes and need for ecosystem-specific research are emphasised., (© 2022 The Authors. European Journal of Soil Science published by John Wiley & Sons Ltd on behalf of British Society of Soil Science.)- Published
- 2022
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7. Factors influencing US osteopathic medical students to choose pathology as a specialty.
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George MR, Johnson KA, Berg MP, Bryant BH, Childs JM, Dixon LR, Holloman A, Karp JK, Knollmann-Ritschel B, Lofgreen A, Prieto VG, Timmons CF, and McCloskey CB
- Abstract
The decline in the number of US allopathic (Medical Doctor or M.D.) medical students matching to pathology residency has been a topic of much discussion at national pathology professional society meetings and in recent publications. A recent survey of fourth-year allopathic medicals students was conducted to better understand the rationale behind students' interest or lack thereof in pathology as a specialty. This study utilizes a similar survey tool gauging osteopathic (Doctor of Osteopathy or D.O.) student knowledge and interest in pathology, and offers insight into a possible growth market for the specialty. Similar to allopathic students, osteopathic students noted that clinical or research opportunities in pathology during medical school, autopsy observation/participation, and participation in pathology interest groups correlated with a greater likelihood of selecting pathology as a specialty. However, some key differences in osteopathic medical school curricular elements including microscope use, gross pathology specimen demonstrations, case-based learning by pathologists, exposure to pathology during other rotations, awareness of a pathology interest group, as well as an overall understanding of the everyday work of a pathologist were noted. Experiential exposure to pathology, and direct mentorship from pathologists may present an opportunity for pathology professional organizations, and pathology residency programs to partner with osteopathic medical schools to increase interest in the field, and aid in pipeline development., (© 2022 Published by Elsevier Inc. on behalf of Association of Pathology Chairs.)
- Published
- 2022
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8. Positive Job Search Experience for New Pathologists Seeking First Employment Between 2017 and 2019.
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Shyu I, Johnson KA, Gratzinger D, Brissette MD, Childs JM, Dixon LR, George MR, McCloskey CB, Prieto VG, Rojiani AM, Timmons CF, and Hoffman RD
- Subjects
- Adult, Female, Humans, Male, Surveys and Questionnaires, Employment statistics & numerical data, Pathologists
- Abstract
Context.—: An aging population calls for an adequate response in the workforce of medical professionals. The field of pathology has seen a downward trend in numbers of graduating US allopathic medical students choosing the specialty. Concerns about the job market after residency and fellowship graduation may be a contributing factor., Objective.—: To provide an update on the trends emerging from a survey of pathology graduates' job search experience for their first nonfellowship position., Design.—: Data from an annual job search survey sent by the College of American Pathologists Graduate Medical Education Committee between 2017 and 2019 to College of American Pathologists junior members and fellows in practice 3 years or less actively looking for a nonfellowship position was analyzed. Various indicators of the job search experience were compared year to year and with the previously published 2012 to 2016 benchmark data., Results.—: Analysis revealed positive trends between the 2017 to 2019 data and the 2012 to 2016 benchmark data, including participants' perceiving more ease in finding a position, improved availability of jobs in their subspecialty choice, and higher ratings of satisfaction with the position accepted, as well as a greater proportion of respondents finding a position within 6 months of initiating their job search., Conclusions.—: The job market for pathology residents and fellows looking for their first nonfellowship position has improved with respect to multiple indicators, such as ease of finding a position, length of job search, and satisfaction with the position accepted when comparing 2017 to 2019 data with the 2012 to 2016 benchmark data., Competing Interests: The views expressed are those of the authors and do not reflect the official policy of the Department of the Army/Navy/Air Force, Department of Defense, or the U.S. Government. The identification of specific products or scientific instrumentation does not constitute endorsement or implied endorsement on the part of the author, Department of Defense, or any component agency.
- Published
- 2021
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9. The Impact of the Coronavirus Disease 2019 (COVID-19) Pandemic on the 2019-2020 Job Search for Newly Trained Pathologists.
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George MR, Johnson KA, Childs JM, Dixon LR, Gratzinger DA, Hoffman RD, Holloman A, Karp JK, Knollmann-Ritschel BEC, Lofgreen A, Prieto VG, Timmons CF, and McCloskey CB
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- COVID-19 epidemiology, COVID-19 virology, Career Choice, Humans, Pandemics, Pathologists standards, Personnel Selection standards, Personnel Selection statistics & numerical data, Professional Competence standards, SARS-CoV-2 physiology, Surveys and Questionnaires statistics & numerical data, COVID-19 prevention & control, Job Application, Pathologists statistics & numerical data, SARS-CoV-2 isolation & purification
- Published
- 2021
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10. Will I Need to Move to Get My First Job?: Geographic Relocation and Other Trends in the Pathology Job Market.
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George MR, Johnson KA, Gratzinger DA, Brissette MD, McCloskey CB, Conran RM, Dixon LR, Roberts CA, Rojiani AM, Shyu I, Timmons CF Jr, and Hoffman RD
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- Career Mobility, Employment statistics & numerical data, Humans, Surveys and Questionnaires, Pathologists supply & distribution, Pathology, Clinical trends
- Abstract
Context.—: There is an ongoing perception that the pathology job market is poor, which may be discouraging medical students from pursuing the specialty. Academic pathologists believe that jobs are available but relocation may be necessary., Objective.—: To identify trends regarding the geographic relocation of pathologists taking their first job after training., Design.—: The College of American Pathologists (CAP) Graduate Medical Education Committee has sent an annual job search survey from 2012-2016 to CAP junior members and fellows in practice for 3 years or less and seeking their first job. Data were analyzed across demographics and geographic domains consisting of the following: stayed at same institution/city, relocated within the same region, or relocated to a different region. Standard statistical methods were used., Results.—: Of 501 respondents, 421 reported completing combined anatomic pathology (AP)/clinical pathology (CP) training, while 80 reported AP- or CP-only training. Of the 421 AP/CP respondents, 109 (26%) stayed at the same institution or city, while of the 80 AP- or CP-only respondents, 36 (45%) stayed at the same institution or city. One hundred ninety-nine respondents completed surgical pathology fellowships with 124 (62%) general/oncologic surgical pathology and 75 (38%) subspecialty surgical pathology trainees. Job seekers who completed general surgical pathology/surgical oncologic pathology fellowship accounted for 34 of 52 (65%) of those remaining at the same institution or city, while those with subspecialty training accounted for 40 of 77 (52%) of those relocating to a different region. Relocation did not demonstrate any significant trends in regard to other demographics studied., Conclusions.—: The pathology job market appears stable with no precedent for geographic hardship.
- Published
- 2020
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11. Gender Parity in Gainful Employment and Other Gender Trends in the Job Market for Recent Pathology Graduates.
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Shyu I, Johnson KA, George MR, Gratzinger D, Brissette MD, Childs JM, Conran RM, Dixon LR, McCloskey CB, Prieto VG, Roberts CA, Rojiani AM, Timmons CF Jr, and Hoffman RD
- Subjects
- Career Mobility, Employment statistics & numerical data, Female, Humans, Male, Surveys and Questionnaires, Pathologists, Pathology, Clinical statistics & numerical data, Sexism statistics & numerical data
- Abstract
Context.—: Gender-based barriers to equal salary, career advancement, and leadership still exist in medicine. Herein we provide the first report of data comparing the experiences of men and women seeking their first nonfellowship position in pathology., Objective.—: To identify gender trends regarding pathologists taking their first job after training and the relationship to various demographic factors, job search satisfaction, and outcome., Design.—: Aggregate data from the College of American Pathologists Graduate Medical Education Committee Job Market surveys (2015-2018) were analyzed across multiple domains including residency focus, number and subspecialty of fellowships completed, and extent to which expectations were met in regard to work duties, geographic preference, benefits, and salary. These data were examined in the context of assessing gender-based differences., Results.—: Comparable results were identified in all measured outcomes according to gender. There were no differences between gender and medical school type, relocation, residency training focus, number of fellowships completed, overall satisfaction with position accepted, salary, or extent to which the position met expectations. Similarly, there were also no discrepancies between gender and the geographic region in which positions were accepted, practice setting, practice subspecialty, partnership track, length of job search, or difficulty finding a position., Conclusions.—: Analysis from 4 years of job market survey data shows equivalent results between men and women looking for their first nonfellowship position in pathology. There were no significant differences with regard to difficulty finding a position, overall satisfaction with the position accepted, salary, benefits, or access to partnership track.
- Published
- 2020
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12. Entry of Graduates of US Pathology Residency Programs Into the Workforce: Cohort Data Between 2008 and 2016 Remain Positive and Stable.
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Timmons CF, Black-Schaffer WS, Naritoku WY, Powell SZ, Johnson KA, Brissette MD, Childs JM, Conran RM, Dixon LR, George MR, Gratzinger D, McCloskey CB, Prieto VG, Roberts CA, Rojiani AM, Shyu I, and Hoffman RD
- Abstract
The pathologist workforce in the United States is a topic of interest to the health-care community as a whole and to institutions responsible for the training of new pathologists in particular. Although a pathologist shortage has been projected, there has been a pervasive belief by medical students and their advisors that there are "no jobs in pathology." In 2013 and again in 2017, the Program Directors Section of the Association of Pathology Chairs conducted surveys asking pathology residency directors to report the employment status of each of their residents graduating in the previous 5 years. The 2013 Program Directors Section survey indicated that 92% of those graduating in 2010 had obtained employment within 3 years, and 94% of residents graduating in 2008 obtained employment within 5 years. The 2017 survey indicated that 96% of those graduating in 2014 had obtained employment in 3 years, and 97% of residents graduating in 2012 obtained positions within 5 years. These findings are consistent with residents doing 1 or 2 years of fellowship before obtaining employment. Stratification of the data by regions of the country or by the size of the residency programs does not show large differences. The data also indicate a high percentage of employment for graduates of pathology residency programs and a stable job market over the years covered by the surveys., Competing Interests: Declaration of Conflicting Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2020.)
- Published
- 2020
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13. Development of Professionalism in Graduate Medical Education: A Case-Based Educational Approach From the College of American Pathologists' Graduate Medical Education Committee.
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Conran RM, Powell SZ, Domen RE, McCloskey CB, Brissette MD, Cohen DA, Dixon LR, George MR, Gratzinger DA, Post MD, Roberts CA, Rojiani AM, Timmons CF Jr, Johnson K, and Hoffman RD
- Abstract
Professionalism and physician well-being are important topics in academic medicine. Lapses in professional judgment may lead to disciplinary action and put patient's health at risk. Within medical education, students and trainees are exposed to professionalism in the institution's formal curriculum and hidden curriculum. Development of professionalism starts early in medical school. Trainees entering graduate medical education already have developed professional behavior. As a learned behavior, development of professional behavior is modifiable. In addition to role modeling by faculty, other modalities are needed. Use of case vignettes based on real-life issues encountered in trainee and faculty behavior can serve as a basis for continued development of professionalism in trainees. Based on the experience of program directors and pathology educators, case vignettes were developed in the domains of service, research, and education and subdivided into the areas of duty, integrity, and respect. General and specific questions pertaining to each case were generated to reinforce model behavior and overcome professionalism issues encountered in the hidden curriculum. To address physician burnout, cases were generated to provide trainees with the skills to deal with burnout and promote well-being., Competing Interests: Declaration of Conflicting Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
- Published
- 2018
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14. Xenobiotic effects on intestinal stem cell proliferation in adult honey bee (Apis mellifera L) workers.
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Forkpah C, Dixon LR, Fahrbach SE, and Rueppell O
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- Animals, Bromodeoxyuridine metabolism, Cell Nucleus drug effects, Cell Nucleus metabolism, Cell Proliferation drug effects, Hierarchy, Social, Honey, Stem Cells drug effects, Stem Cells metabolism, Bees cytology, Intestines cytology, Stem Cells cytology, Xenobiotics pharmacology
- Abstract
The causes of the current global decline in honey bee health are unknown. One major group of hypotheses invokes the pesticides and other xenobiotics to which this important pollinator species is often exposed. Most studies have focused on mortality or behavioral deficiencies in exposed honey bees while neglecting other biological functions and target organs. The midgut epithelium of honey bees presents an important interface between the insect and its environment. It is maintained by proliferation of intestinal stem cells throughout the adult life of honey bees. We used caged honey bees to test multiple xenobiotics for effects on the replicative activity of the intestinal stem cells under laboratory conditions. Most of the tested compounds did not alter the replicative activity of intestinal stem cells. However, colchicine, methoxyfenozide, tetracycline, and a combination of coumaphos and tau-fluvalinate significantly affected proliferation rate. All substances except methoxyfenozide decreased proliferation rate. Thus, the results indicate that some xenobiotics frequently used in apiculture and known to accumulate in honey bee hives may have hitherto unknown physiological effects. The nutritional status and the susceptibility to pathogens of honey bees could be compromised by the impacts of xenobiotics on the maintenance of the midgut epithelium. This study contributes to a growing body of evidence that more comprehensive testing of xenobiotics may be required before novel or existing compounds can be considered safe for honey bees and other non-target species.
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- 2014
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15. Pleiotropy of segregating genetic variants that affect honey bee worker life expectancy.
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Dixon LR, McQuage MR, Lonon EJ, Buehler D, Seck O, and Rueppell O
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- Aging genetics, Animals, Bees physiology, Behavior, Animal physiology, Gene Frequency, Genetic Variation physiology, Genotype, Microsatellite Repeats genetics, Pollen, Polymorphism, Single Nucleotide, Quantitative Trait Loci, Bees genetics, Genetic Pleiotropy physiology, Life Expectancy
- Abstract
In contrast to many other complex traits, the natural genetic architecture of life expectancy has not been intensely studied, particularly in non-model organisms, such as the honey bee (Apis mellifera L.). Multiple factors that determine honey bee worker lifespan have been identified and genetic analyses have been performed on some of those traits. Several of the traits are included in a suite of correlated traits that form the pollen hoarding syndrome, which was named after the behavior to store surplus pollen in the nest and is tied to social evolution. Here, seven quantitative trait loci that had previously been identified for their effects on different aspects of the pollen hoarding syndrome were studied for their genetic influence on the survival of adult honey bee workers. To gain a more comprehensive understanding of the genetic architecture of worker longevity, a panel of 280 additional SNP markers distributed across the genome was also tested. Allelic distributions were compared between young and old bees in two backcross populations of the bi-directionally selected high- and low-pollen hoarding strain. Our results suggest a pleiotropic effect of at least one of the behavioral quantitative trait loci on worker longevity and one significant and several other putative genetic effects in other genomic regions. At least one locus showed evidence for strong antagonistic pleiotropy and several others suggested genetic factors that influence pre-emergence survival of worker honey bees. Thus, the predicted association between worker lifespan and the pollen hoarding syndrome was supported at the genetic level and the magnitude of the identified effects also strengthened the view that naturally segregating genetic variation can have major effects on age-specific survival probability in the wild., (Copyright © 2012 Elsevier Inc. All rights reserved.)
- Published
- 2012
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16. Randomized, controlled trial of standard, large-capacity versus jumbo biopsy forceps for polypectomy of small, sessile, colorectal polyps.
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Draganov PV, Chang MN, Alkhasawneh A, Dixon LR, Lieb J, Moshiree B, Polyak S, Sultan S, Collins D, Suman A, Valentine JF, Wagh MS, Habashi SL, and Forsmark CE
- Subjects
- Aged, Chi-Square Distribution, Colonic Polyps pathology, Colonic Polyps surgery, Female, Humans, Male, Middle Aged, Rectum pathology, Rectum surgery, Regression Analysis, Time Factors, Intestinal Polyps pathology, Intestinal Polyps surgery, Surgical Instruments
- Abstract
Background: Polypectomy with cold biopsy forceps is a frequently used technique for removal of small, sessile, colorectal polyps. Jumbo forceps may lead to more effective polypectomy because of the larger size of the forceps cup., Objective: To evaluate the efficiency of cold jumbo biopsy forceps compared with standard forceps for polypectomy of small, sessile, colorectal polyps., Design: Randomized, controlled trial., Setting: Outpatient endoscopy center., Patients: This study involved 140 patients found to have at least one eligible polyp defined as a sessile polyp measuring ≤6 mm., Intervention: Polypectomy with cold biopsy forceps., Main Outcome Measurements: Complete visual polyp eradication with one forceps bite., Results: In 140 patients, a total of 305 eligible polyps were detected (151 removed with jumbo forceps and 154 with standard forceps). Complete visual eradication of the polyp with one forceps bite was achieved in 78.8% of the jumbo forceps group and 50.7% of the standard forceps group (P < .0001). Biopsies from the polypectomy sites of adenomatous polyps thought to be visually completely eradicated with one bite showed a trend toward a higher complete histologic eradication rate with the jumbo forceps (82.4%) compared with the standard forceps (77.4%), but the difference did not reach statistical significance (P = .62). The withdrawal time for visual inspection of the colon and time to perform polypectomies were significantly shorter in the jumbo forceps group (mean 21.43 vs 18.23 minutes; P = .02)., Limitations: Lack of blinding to the type of forceps used., Conclusion: The jumbo biopsy forceps is superior to the standard forceps in removing small, sessile polyps. (, Clinical Trial Registration Number: NCT00855790.)., (Copyright © 2012 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.)
- Published
- 2012
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17. Labial salivary gland biopsy in the investigation of neonatal hemochromatosis.
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Magliocca KR, Lewis EL, Bhattacharyya I, Cohen DM, and Dixon LR
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- Biopsy, Carnitine therapeutic use, Cholagogues and Choleretics therapeutic use, Female, Hemochromatosis blood, Hemochromatosis drug therapy, Humans, Infant, Newborn, Infant, Premature, Iron analysis, Liver Failure blood, Liver Regeneration, Mouth Mucosa chemistry, Mouth Mucosa pathology, Salivary Glands, Minor chemistry, Ursodeoxycholic Acid therapeutic use, Vitamin K therapeutic use, Vitamins therapeutic use, Hemochromatosis pathology, Immunoglobulins, Intravenous therapeutic use, Lip pathology, Liver Failure pathology, Salivary Glands, Minor pathology
- Published
- 2011
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18. Autoimmune esophagitis: IgG4-related tumors of the esophagus.
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Lopes J, Hochwald SN, Lancia N, Dixon LR, and Ben-David K
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- Autoimmune Diseases immunology, Autoimmune Diseases surgery, Biopsy, Fine-Needle, Esophagectomy, Esophagitis immunology, Esophagitis surgery, Humans, Immunoglobulin G immunology, Male, Young Adult, Autoimmune Diseases pathology, Esophagitis pathology, Esophagus pathology, Plasma Cells pathology
- Abstract
We present a case of a 23-year-old gentleman who presented with dysphagia, weight loss, and recurrent esophageal strictures requiring multiple dilatations. An endoscopic ultrasound with esophagogastroduodenoscopy revealed a mass present in the distal esophagus. Fine needle aspiration suggested that the mass in the lower esophagus resembled a gastrointestinal stromal tumor. After surgical resection, final pathologic analysis revealed that the tumor was comprised of benign-appearing fibroinflammatory cells with an increase and predominance of IgG4-positive plasma cells. The microscopic appearance was consistent with a benign condition as a result of an IgG4-related process. He did not, however, have any other symptoms indicative of systemic autoimmune disease or connective tissue disorders. We present the pre-operative imaging, operative management, pathologic diagnosis, and literature review of this rare condition and the first known report of autoimmune esophagitis as part of the IgG4 spectrum of diseases.
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- 2010
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19. The role of hydrostatic pressure on developmental stages of Pomatoceros lamarcki (Polychaeta: Serpulidae) exposed to water accommodated fractions of crude oil and positive genotoxins at simulated depths of 1000-3000 m.
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Vevers WF, Dixon DR, and Dixon LR
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- Animals, Cell Division drug effects, Environmental Exposure, Hydrostatic Pressure, Polychaeta cytology, Polychaeta drug effects, Environmental Monitoring, Mutagens toxicity, Petroleum toxicity, Polychaeta growth & development, Water Pollutants, Chemical toxicity
- Abstract
The effect of high hydrostatic pressures on the ecotoxicological profile of pollutants is an unexplored research area. Using Pomatoceros lamarcki as a surrogate organism for this eco-barotoxicological study, it was found that in a 48 h larval bioassay with water accommodated fractions (WAF) of crude oil of up to 15.1 mg L(-1) (total hydrocarbon content) and hydrostatic pressures up to 300 bar (3000 m), an additive response was found (p < 0.001) rather than any synergism (p = 0.881). Comprehensive cytogenetic analysis of 6-h (15 degrees C) embryos exposed to WAF (0.19 mg L(-1)) at 100 bar showed no effects on mitotic fidelity or cell division rate over the 1 bar treatment. However, embryo's treated with the clastogen mitomycin-c at 100 bar exhibited a significant increase in mitotic aberrations over 1 bar treated as was the case with hypo/hypersaline treatments (p < 0.05). Conversely, an increase in hydrostatic pressure actually reduced the effects of spindle inhibition by the aneugen colchicine (p < 0.05)., (Copyright 2009 Elsevier Ltd. All rights reserved.)
- Published
- 2010
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20. Pancreatic heterotopia masquerading as duodenal carcinoid.
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Liu H, Dixon LR, and George TJ
- Published
- 2009
21. Pancreatic adenocarcinoma patients with localised chronic severe pancreatitis show an increased number of single beta cells, without alterations in fractional insulin area.
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Campbell-Thompson M, Dixon LR, Wasserfall C, Monroe M, McGuigan JM, Schatz D, Crawford JM, and Atkinson MA
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- Adult, Aged, Aged, 80 and over, Autopsy, Cell Nucleus pathology, Female, Humans, Immunohistochemistry, Ki-67 Antigen analysis, Male, Middle Aged, Reference Values, Young Adult, Adenocarcinoma pathology, Insulin analysis, Insulin-Secreting Cells pathology, Pancreatic Neoplasms pathology, Pancreatitis, Chronic pathology
- Abstract
Aims/hypothesis: Recent histological analysis of pancreases obtained from patients with long-standing type 1 diabetes identified chronic islet inflammation and limited evidence suggestive of beta cell replication. Studies in rodent models also suggest that beta cell replication can be induced by certain inflammatory cytokines and by gastrin. We therefore tested the hypothesis that beta cell replication is observed in non-autoimmune human pancreatic disorders in which localised inflammation or elevated gastrin levels are present., Methods: Resected operative pancreatic specimens were obtained from patients diagnosed with primary adenocarcinoma (with or without chronic severe pancreatitis) or gastrinoma. Additional pancreatic tissue was obtained from autopsy control patients. Immunohistochemistry was used to assess fractional insulin area, beta cell number and replication rate and differentiation factors relevant to beta cell development., Results: Fractional insulin area was similar among groups. Patients with pancreatic adenocarcinoma and localised chronic severe pancreatitis displayed significant increases in the number of single beta cells, as well as increased beta cell replication rate and levels of neurogenic differentiation 1 in islets. Patients with gastrinoma demonstrated significant increases in the number of single beta cells, but the beta cell replication rate and islet differentiation factor levels were similar to those in the control group., Conclusions/interpretation: These findings indicate that chronic severe pancreatic inflammation can be associated with significant effects on beta cell number or replication rate, depending on the distribution of the cells. This information may prove useful for attempts seeking to design therapies aimed at inducing beta cell replication as a means of reversing diabetes.
- Published
- 2009
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22. Autoimmune pancreatitis and concurrent small lymphocytic lymphoma: not just a coincidence?
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Kim T, Grobmyer SR, Dixon LR, Allan RW, and Hochwald SN
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- Aged, Autoimmune Diseases surgery, Biopsy, Needle, Blood Chemical Analysis, Cholangiography, Follow-Up Studies, Humans, Immunohistochemistry, Jaundice diagnosis, Jaundice etiology, Leukemia, Lymphocytic, Chronic, B-Cell surgery, Male, Pancreatic Function Tests, Pancreaticoduodenectomy methods, Pancreatitis immunology, Pancreatitis surgery, Risk Assessment, Tomography, X-Ray Computed, Treatment Outcome, Autoimmune Diseases complications, Autoimmune Diseases diagnosis, Leukemia, Lymphocytic, Chronic, B-Cell complications, Leukemia, Lymphocytic, Chronic, B-Cell diagnosis, Pancreatitis complications, Pancreatitis pathology
- Abstract
Case: A 76-year-old gentleman presented with painless jaundice, weight loss, and anorexia. Computed tomography imaging revealed fullness of the pancreatic head and multiple enlarged retroperitoneal lymph nodes. Cholangiogram revealed a distal common bile duct stricture. Due to concerns of malignancy, the patient underwent operative exploration. Several enlarged lymph nodes in the aortocaval region and a firm hard mass in the pancreatic head were found. Frozen section from one of the lymph nodes was suspicious for low-grade lymphoma. A pancreaticoduodenectomy was performed. Histologic analysis of the pancreatic head revealed a lymphoplasmacytic infiltrate with stromal fibrosis consistent with autoimmune pancreatitis. The retroperitoneal lymph nodes were involved by small lymphocytic lymphoma., Discussion: Autoimmune pancreatitis is the most common benign diagnosis after pancreatic resection for presumed malignancy. It has a well-documented association with autoimmune conditions, such as Sjögren's syndrome, inflammatory bowel disease, and sclerosing cholangitis. Additionally, chronic lymphocytic leukemia-small lymphocytic lymphoma is often associated with autoimmune phenomena, most notably autoimmune hemolytic anemia. However, an association between autoimmune pancreatitis and small lymphocytic lymphoma has not been previously described. To our knowledge, this is the first reported case of a patient with concurrent autoimmune pancreatitis and small lymphocytic lymphoma.
- Published
- 2008
- Full Text
- View/download PDF
23. Isolated lymphoplasmacytic sclerosing pancreatitis involving the pancreatic tail.
- Author
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Kim T, Grobmyer SR, Dixon LR, and Hochwald SN
- Subjects
- Chronic Disease, Diagnosis, Differential, Female, Follow-Up Studies, Humans, Middle Aged, Pancreas diagnostic imaging, Pancreatitis diagnostic imaging, Pancreatitis surgery, Radiography, Sclerosis, Pancreas pathology, Pancreaticoduodenectomy methods, Pancreatitis pathology
- Abstract
We present an interesting case of a 62-year-old woman with a 3-month history of vague, left-sided abdominal pain. CT imaging revealed a hypodense lesion in the tail of the pancreas. The patient had no history of pancreatitis or autoimmune diseases. Laboratory testing revealed a normal CA19-9 (33 U/mL) and an elevated IgG4 (133 mg/dL). Due to concerns of pancreatic malignancy, she underwent operation. We found a dense, inflammatory mass in the tail of the pancreas, which was removed via an open distal pancreatectomy with splenectomy. Histologic analysis revealed a pancreas with sclerotic ducts and surrounding lymphoplasmacytic inflammation most consistent with lymphoplasmacytic sclerosing pancreatitis (LPSP). LPSP, also termed autoimmune pancreatitis, is a benign disease of the pancreas, which can mimic pancreatic adenocarcinoma. It is the most common benign finding diagnosed on pathology after pancreatic resection for presumed malignancy. LPSP most commonly involves the head and, more uncommonly, the tail of the pancreas. It can be successfully treated with steroids obviating the need for resection. IgG4 levels may assist in recognition of this disease. As our experience with utilization of IgG4 testing and knowledge of the systemic nature of LPSP increase, patients with this disease may be spared unnecessary resection.
- Published
- 2008
24. Elevation of serum IgG4 in Western patients with autoimmune sclerosing pancreatocholangitis: a word of caution.
- Author
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Hochwald SN, Hemming AW, Draganov P, Vogel SB, Dixon LR, and Grobmyer SR
- Subjects
- Adolescent, Aged, Autoimmune Diseases surgery, Cholangitis, Sclerosing surgery, Female, Humans, Male, Middle Aged, Pancreatitis surgery, Reference Values, Retrospective Studies, United States, Autoimmune Diseases blood, Cholangitis, Sclerosing blood, Immunoglobulin G blood, Pancreatitis blood
- Abstract
Background: Autoimmune pancreatocholangitis is characterized by sclerosing inflammation of the biliary tree or pancreatic duct and can mimic pancreaticobiliary malignancy. Serum immunoglobin (Ig) G4 values seem to be helpful in distinguishing autoimmune pancreatocholangitis from pancreatic malignancy in the Japanese population; however, its significance in the Western population has not been well studied., Methods: We report a retrospective analysis of 7 consecutive patients with autoimmune pancreatocholangitis and compare them to 23 patients with pancreatic malignancy. Clinical presentation, diagnostic tests, and preoperative IgG4 levels were reviewed in all patients. Presence of autoimmune pancreatocholangitis or pancreatic malignancy was determined by pathologic analysis in all patients and reviewed by a single pathologist., Results: In all patients, autoimmune pancreatocholangitis manifested in a similar fashion to pancreatic malignancy. Median IgG4 levels were far lower in pancreatic cancer patients with localized, resectable disease (24 mg/dL), locally advanced disease (24 mg/dL), and metastatic disease (28 mg/dL) as compared with patients with autoimmune pancreatocholangitis (142 mg/dL, P < .05). Only one patient with pancreatic cancer had an IgG4 level that was >100 mg/dL. In contrast, all patients with autoimmune pancreatitis or cholangitis had levels >100 mg/dL. However, in five of these seven patients, IgG4 levels were below the upper limits of normal., Conclusions: Autoimmune pancreatocholangitis mimics pancreatobiliary malignancy. Serum IgG4 values seem to be helpful in distinguishing autoimmune pancreatocholangitis from malignancy in the Western population. However, absolute values seem to be lower in the United States compared with Japan. The upper limit of normal as reported in laboratories in the United States may not be useful in identifying abnormally high IgG4 values. A new upper limit of normal may need to be defined because IgG subclass determinations are being used more frequently in Western patients with biliary obstruction.
- Published
- 2008
- Full Text
- View/download PDF
25. Contemporary results with ampullectomy for 29 "benign" neoplasms of the ampulla.
- Author
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Grobmyer SR, Stasik CN, Draganov P, Hemming AW, Dixon LR, Vogel SB, and Hochwald SN
- Subjects
- Adenoma pathology, Adult, Aged, Aged, 80 and over, Carcinoma pathology, Cohort Studies, Humans, Middle Aged, Neoplasm Invasiveness, Predictive Value of Tests, Retrospective Studies, Treatment Outcome, Adenoma surgery, Ampulla of Vater, Carcinoma surgery, Common Bile Duct Neoplasms pathology, Common Bile Duct Neoplasms surgery
- Abstract
Background: Ampullectomy may be an appropriate oncologic procedure in selected patients. Sparse data exist on procedure-related complications and the relationship between histologic analysis and outcomes., Study Design: We retrospectively reviewed our experience with ampullectomy in 29 patients with a preoperative benign histologic diagnosis over 15 years (1991 to 2006). Presenting signs, symptoms, and preoperative diagnostic studies were reviewed. Postoperative complications and followup for recurrence were recorded. The abilities of preoperative histologic biopsy, intraoperative frozen section, and final histologic analysis to guide management and predict outcomes were determined., Results: Median age was 63 years. Jaundice was present in 30% of patients. Median length of hospital stay was 9 days. Forty-five percent of patients had a complication, and there was one postoperative mortality (3%). Ampullary adenomatous neoplasms were present in 89% of patients. Preoperative biopsy had complete concordance with final pathology in 76% of patients. Preoperative biopsy and intraoperative frozen section failed to identify carcinoma in four patients. Pancreaticoduodenectomy was performed within 7 days in the postoperative period in three of these patients. After ampullectomy (median followup=16 months), recurrences were identified in two patients (8%) with benign tumors. No patients with high-grade dysplasia (n=4) have had recurrence., Conclusions: Preoperative biopsy and intraoperative frozen section analysis have limitations in the management of patients undergoing ampullectomy. High-grade dysplasia on preoperative biopsy is not an absolute contraindication to ampullectomy. Morbidity of ampullectomy is significant, but longterm outcomes of this procedure, in patients without invasive malignancy, are acceptable.
- Published
- 2008
- Full Text
- View/download PDF
26. Detection of endogenous biomolecules in Barrett's esophagus by Fourier transform infrared spectroscopy.
- Author
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Wang TD, Triadafilopoulos G, Crawford JM, Dixon LR, Bhandari T, Sahbaie P, Friedland S, Soetikno R, and Contag CH
- Subjects
- Barrett Esophagus classification, Biopsy, Cell Transformation, Neoplastic, Esophagus pathology, Gastric Mucosa pathology, Humans, Spectroscopy, Fourier Transform Infrared methods, Barrett Esophagus pathology
- Abstract
Fourier transform infrared (FTIR) spectroscopy provides a unique molecular fingerprint of tissue from endogenous sources of light absorption; however, specific molecular components of the overall FTIR signature of precancer have not been characterized. In attenuated total reflectance mode, infrared light penetrates only a few microns of the tissue surface, and the influence of water on the spectra can be minimized, allowing for the analyses of the molecular composition of tissues. Here, spectra were collected from 98 excised specimens of the distal esophagus, including 38 squamous, 38 intestinal metaplasia (Barrett's), and 22 gastric, obtained endoscopically from 32 patients. We show that DNA, protein, glycogen, and glycoprotein comprise the principal sources of infrared absorption in the 950- to 1,800-cm(-1) regime. The concentrations of these biomolecules can be quantified by using a partial least-squares fit and used to classify disease states with high sensitivity, specificity, and accuracy. Moreover, use of FTIR to detect premalignant (dysplastic) mucosa results in a sensitivity, specificity, positive predictive value, and total accuracy of 92%, 80%, 92%, and 89%, respectively, and leads to a better interobserver agreement between two gastrointestinal pathologists for dysplasia (kappa = 0.72) versus histology alone (kappa = 0.52). Here, we demonstrate that the concentration of specific biomolecules can be determined from the FTIR spectra collected in attenuated total reflectance mode and can be used for predicting the underlying histopathology, which will contribute to the early detection and rapid staging of many diseases.
- Published
- 2007
- Full Text
- View/download PDF
27. Early histologic changes in fibrosing cholestatic hepatitis C.
- Author
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Dixon LR and Crawford JM
- Subjects
- Adult, Aged, Female, Fibrosis, Graft Rejection pathology, Humans, Male, Middle Aged, Recurrence, Cholestasis, Intrahepatic pathology, Cholestasis, Intrahepatic surgery, Hepatitis C pathology, Hepatitis C surgery, Liver Transplantation
- Abstract
Recurrent hepatitis C (RHCV) after liver transplantation is almost universal, and occasional patients will have an aggressive course characterized histologically by pericellular/sinusoidal fibrosis and cholestasis, known as fibrosing cholestatic hepatitis (FCH). The early stages and evolution of this disease have not been well characterized. A total of 77 liver biopsies performed for indication (nonprotocol) were evaluated for necroinflammation, rejection, cholestasis, and fibrosis. Control groups were composed of protocol biopsies from HCV transplant patients (10 biopsies) as well as non-HCV transplant patients (6 biopsies). Scoring for necroinflammation, rejection, and fibrosis were compiled using standard criteria (hepatic activity index, Banff, Ishak, METAVIR). Pericellular fibrosis was staged with a novel "sinusoidal" system. A cholestasis scoring system was developed to quantitate parenchymal and portal features of cholestasis. Biopsies were categorized as rejection, RHCV, FCH, and stable based on histology and clinical information. FCH was found to have a higher fibrosis stage overall when compared to most diagnostic groups, regardless of the staging system used. Additionally, sinusoidal fibrosis was significantly higher in the FCH diagnosis group. Cholestasis was more prominent in biopsies of FCH in all comparisons. In conclusion, the presence of cholestasis and fibrosis with mild to moderate RHCV should raise the suspicion of FCH. When studying the evolution of these cases, the first abnormality to appear is RHCV and cholestasis, fibrosis develops soon after, and both continue to worsen until the point of allograft failure or patient death., ((c) 2006 AASLD.)
- Published
- 2007
- Full Text
- View/download PDF
28. Liver-occupying focal nodular hyperplasia and adenomatosis associated with intrahepatic portal vein agenesis requiring orthotopic liver transplantation.
- Author
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Fujita S, Mekeel KL, Fujikawa T, Kim RD, Foley DP, Hemming AW, Howard RJ, Reed AI, and Dixon LR
- Subjects
- Adenoma blood supply, Adenoma diagnostic imaging, Child, Female, Focal Nodular Hyperplasia diagnostic imaging, Humans, Liver Neoplasms blood supply, Liver Neoplasms diagnostic imaging, Tomography, X-Ray Computed, Adenoma surgery, Focal Nodular Hyperplasia surgery, Liver Neoplasms surgery, Liver Transplantation, Portal Vein abnormalities
- Published
- 2006
- Full Text
- View/download PDF
29. Hepatic mucormycosis in a renal transplant recipient.
- Author
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Mekeel KL, Hemming AW, Reed AI, Matsumoto T, Fujita S, Schain DC, Nelson DR, Dixon LR, and Fujikawa T
- Subjects
- Diabetes Mellitus, Type 2 surgery, Fatal Outcome, Female, Humans, Kidney Failure, Chronic surgery, Liver Diseases diagnostic imaging, Middle Aged, Shock, Septic, Tomography, X-Ray Computed, Kidney Transplantation adverse effects, Liver Diseases microbiology, Mucormycosis diagnostic imaging
- Published
- 2005
- Full Text
- View/download PDF
30. The effects of hydrostatic pressure change on DNA integrity in the hydrothermal-vent mussel Bathymodiolus azoricus: implications for future deep-sea mutagenicity studies.
- Author
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Dixon DR, Pruski AM, and Dixon LR
- Subjects
- Animals, Atlantic Ocean, Bivalvia genetics, Comet Assay, Environmental Exposure, Hydrogen Peroxide toxicity, Mutagens toxicity, Time Factors, Bivalvia physiology, DNA Damage, Hydrostatic Pressure adverse effects
- Abstract
Comet and agarose gel electrophoresis (AGE) assays were used to show that haemocytes (blood cells) and gill tissues of vent mussels, Bathymodiolus azoricus, are sensitive to hydrostatic pressure change, but can repair DNA damage induced by retrieval from 840 m to the sea surface. In contrast, animals collected from 1700 m survived for only a few days in the laboratory, which was reflected in their poor DNA quality. These findings support the hypothesis of a physiological barrier to survival around 1000-1500 m depth, which these results show affects both vent and non-vent species alike. Based on in vitro experimental exposures to hydrogen peroxide and MMC, vent mussels appear to have sensitivities to the environmental mutagens that are not significantly different from those of coastal mussels.
- Published
- 2004
- Full Text
- View/download PDF
31. Hemophilic pseudotumor: radiologic-pathologic correlation.
- Author
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Stafford JM, James TT, Allen AM, and Dixon LR
- Subjects
- Adult, Amputation, Surgical methods, Bone Diseases etiology, Bone Diseases surgery, Femur, Hemophilia A complications, Humans, Joint Diseases etiology, Joint Diseases surgery, Knee, Leg, Male, Muscle, Skeletal, Muscular Diseases etiology, Muscular Diseases surgery, Radiography, Thigh, Bone Diseases diagnostic imaging, Bone Diseases pathology, Hemophilia A diagnostic imaging, Joint Diseases diagnostic imaging, Joint Diseases pathology, Muscular Diseases diagnostic imaging, Muscular Diseases pathology
- Published
- 2003
- Full Text
- View/download PDF
32. Marine invertebrate eco-genotoxicology: a methodological overview.
- Author
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Dixon DR, Pruski AM, Dixon LR, and Jha AN
- Subjects
- Anaphase, Aneuploidy, Animals, Chromosome Aberrations, Comet Assay, DNA Damage, DNA Repair, Ecosystem, Environmental Monitoring, Humans, In Situ Hybridization, Fluorescence, Marine Biology, Micronucleus Tests, Mutagenicity Tests, Polyploidy, Sister Chromatid Exchange, Toxicology, Invertebrates genetics, Mutagens toxicity
- Abstract
The last 25 years have seen major advances in the field of mammalian genotoxicology, particularly with the advent of molecular methods, some of which have spilled over into the relatively new field of eco-genotoxicology, which aims to evaluate the impact of contaminants on the natural biota. Unlike mammalian genotoxicology, where the focus is centred on a limited number of model species, efforts in the marine field have generally lacked coordination and focus, with the result that progress has been somewhat slow and fragmented. However, it is recognized that at the DNA and chromosome levels, marine invertebrates express qualitatively similar types of induced damage to that found in higher organisms (e.g. point mutations, strand breaks and chromosomal aberrations). Given that many of these species (bivalve molluscs, crustaceans, polychaete worms, etc.) are linked directly or indirectly to the human food chain, this is an important reason why one should be concerned about their exposure to environmental mutagens and carcinogens, particularly as many of these organisms have the capacity to (i) transform these agents to biologically active metabolites and (ii) accumulate toxicants in their cells and tissues at concentrations several orders of magnitude above that found in the environment. This review covers the advantages and limitations of those cytogenetic and molecular assays that have been used to address the question of genotoxicity in the cells and early life stages of selected marine invertebrate species. It concludes with the recommendation for the adoption of standardized test procedures, leading to a tiered approach in future eco-genotoxicity testing.
- Published
- 2002
- Full Text
- View/download PDF
33. Numerical chromosomal aberrations in the early life-history stages of a marine tubeworm, Pomatoceros lamarckii (Polychaeta: Serpulidae).
- Author
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Wilson JT, Dixon DR, and Dixon LR
- Subjects
- Animals, Dose-Response Relationship, Drug, Female, In Situ Hybridization, Fluorescence, Larva drug effects, Larva genetics, Life Cycle Stages, Male, Mutagenicity Tests methods, Polychaeta drug effects, Polychaeta embryology, Chromosome Aberrations, Colchicine toxicity, Dibutyl Phthalate toxicity, Polychaeta genetics
- Abstract
The marine environment provides a sink for a host of toxic chemicals, directly or inadvertently, released as a result of human activity. Some of these chemicals have the potential to act as aneugens, substances that cause numerical chromosomal aberrations (NCAs). NCAs are one of the most important classes of genetic abnormality and are implicated in a variety of deleterious effects, including premature ageing, birth defects and cancer. Clearly, any increase in the incidence of these agents in the marine environment poses a risk to the indigenous biota and its predators, including man. In this paper, we describe our recent success with applying the fluorescence in situ hybridisation technique (FISH) to detect NCAs in the interphase cell nuclei of Pomatoceros lamarckii, a common rocky shore invertebrate. Given the lack of requirement for any detailed cytogenetic knowledge, the method holds considerable promise for laboratory and field studies in general, and should lend itself to automated screening protocols, where large numbers of cells can be screened rapidly, for example, using a flow cytometer. When exposed either under acute or chronic (viz. adult) exposure conditions, colchicine and di-butylphthalate (DBP) (a widely-used plasticiser), two recognised aneugens, induced significant increases in the levels of NCAs, in the dose range 1 x 10(-6)-5 x 10(-6) M, in both four to eight cell embryo stages and 24 h-old larvae. In keeping with the severely debilitating effects of this class of agent, an inverse correlation was observed between the induced levels of NCAs and larval fitness based on the results of a standard 48-h larval bioassay.
- Published
- 2002
- Full Text
- View/download PDF
34. The University of California, San Diego Nurse-Midwifery Bridge Program. An opportunity to learn intrapartum nursing skills.
- Author
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Hunter LP, Dixon LR, and Lops VR
- Subjects
- California, Curriculum, Humans, Organizational Innovation, Preceptorship, Program Evaluation, Education, Nursing, Graduate, Midwifery education
- Abstract
This article describes an innovative program developed by the University of California, San Diego Nurse-Midwifery Education Program to supplement the experiential background of prospective nurse-midwifery students. This preprogram enables RNs without previous labor and delivery (maternal/newborn) nursing experience to complete the bridge program and enter the UCSD student nurse-midwifery program on the same clinical level as other students and complete it within the standard time frame. The rationale for the program, its structural framework, and evaluation tools are presented. The authors hope that a description of the program will allow other institutions to replicate UCSD's success.
- Published
- 1997
- Full Text
- View/download PDF
35. Anemia in pregnancy.
- Author
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Lops VR, Hunter LP, and Dixon LR
- Subjects
- Anemia, Iron-Deficiency diagnosis, Anemia, Iron-Deficiency drug therapy, Anemia, Iron-Deficiency metabolism, Anemia, Sickle Cell diagnosis, Anemia, Sickle Cell etiology, Anemia, Sickle Cell therapy, Female, Folic Acid Deficiency diagnosis, Folic Acid Deficiency drug therapy, Folic Acid Deficiency metabolism, Humans, Pregnancy, Thalassemia diagnosis, Thalassemia drug therapy, Anemia diagnosis, Anemia metabolism, Anemia therapy, Pregnancy Complications, Hematologic diagnosis, Pregnancy Complications, Hematologic metabolism, Pregnancy Complications, Hematologic therapy
- Abstract
Anemia is the most common hematologic complication of pregnancy and is associated with increased rates of premature birth, low birth weight and perinatal mortality. Iron deficiency is the most common cause of anemia, and most pregnant women benefit from daily supplementation of 30 to 60 mg of elemental iron. Folic acid deficiency, the most common cause of megaloblastic anemia in pregnancy, is associated with open neural tube defects and other complications. It is recommended that daily supplementation with 4 mg of folic acid be started at least one month before conception and continued through the first trimester. Other less common causes of anemia include glucose-6-phosphate dehydrogenase deficiency, sickle cell trait and disease, and the thalassemias. The primary care provider should emphasize risk evaluation, dietary and preconceptual counseling, testing and appropriate treatment.
- Published
- 1995
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