130 results on '"Lawrence EC"'
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2. Die SPINK1 N34S Mutation ist nicht mit Typ 2 Diabetes Mellitus in den USA assoziiert
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Schneider, A, primary, Lawrence, EC, additional, Barmada, MM, additional, Norris, JM, additional, Hamman, RF, additional, Marshall, JA, additional, Ferrell, RE, additional, and Whitcomb, DC, additional
- Published
- 2015
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3. Diagnosis and Management of Lung Allograft Rejection
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Lawrence Ec
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Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,Lung ,business.industry ,medicine.medical_treatment ,respiratory system ,respiratory tract diseases ,Surgery ,Transplantation ,medicine.anatomical_structure ,Allograft rejection ,Medicine ,Lung transplantation ,business ,Intensive care medicine - Abstract
Improvements in our understanding of the mechanisms underlying the rejection coupled with the development of novel approaches to dealing with the rejection process have allowed successful lung and heart-lung transplantation. Nonetheless, successful lung transplantation is still limited by acute rejection. This article defines the rejection process and outlines current approaches to preventing and treating this major clinical problem.
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- 1990
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4. Surgical correction of gastroesophageal reflux in lung transplant patients is associated with decreased effector CD8 cells in lung lavages: a case series.
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Neujahr DC, Mohammed A, Ulukpo O, Force SD, Ramirez AM, Pelaez A, Lawrence EC, Larsen CP, Kirk AD, Neujahr, David C, Mohammed, Aminu, Ulukpo, Onome, Force, Seth D, Ramirez, Allan M, Pelaez, Andres, Lawrence, E Clinton, Larsen, Christian P, and Kirk, Allan D
- Abstract
Background: Lung transplantation is associated with a high incidence of gastroesophageal reflux disease (GERD). The presence of GERD is considered a risk factor for the subsequent development of obliterative bronchiolitis (OB), and surgical correction of GERD by gastric fundoplication (GF) may be associated with increased freedom from OB. The mechanisms underlying a protective effect from OB remain elusive. The objective of this study was to analyze the flow cytometric properties of BAL cells in patients who have undergone GF early after transplant.Methods: In a single-center lung transplant center, eight patients with GERD who were in the first transplant year underwent GF. Prior to and immediately following GF, BAL cells were analyzed by polychromatic flow cytometry. Spirometry was performed before and after GF.Results: GF was associated with a significant reduction in the frequency of BAL CD8 lymphocytes expressing the intracellular effector marker granzyme B, compared with the pre-GF levels. Twenty-six percent of CD8 cells were granzyme Bhi pre-GF compared with 12% of CD8 cells post-GF (range 8%-50% pre-GF, 2%-24% post-GF, P = .01). In contrast, GF was associated with a significant interval increase in the frequency of CD8 cells with an exhausted phenotype (granzyme Blo, CD127lo, PD1hi) from 12% of CD8 cells pre-GF to 24% post-GF (range 1.7%-24% pre-GF and 11%-47% post-GF, P = .05). No significant changes in spirometry were observed during the study interval.Conclusions: Surgical correction of GF is associated with a decreased frequency of potentially injurious effector CD8 cells in the BAL of lung transplant recipients. [ABSTRACT FROM AUTHOR]- Published
- 2010
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5. Extended valganciclovir prophylaxis to prevent cytomegalovirus after lung transplantation: a randomized, controlled trial.
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Palmer SM, Limaye AP, Banks M, Gallup D, Chapman J, Lawrence EC, Dunitz J, Milstone A, Reynolds J, Yung GL, Chan KM, Aris R, Garrity E, Valentine V, McCall J, Chow SC, Davis RD, Avery R, Palmer, Scott M, and Limaye, Ajit P
- Abstract
Background: Cytomegalovirus (CMV) is the most prevalent opportunistic infection after lung transplantation. Current strategies do not prevent CMV in most at-risk patients.Objective: To determine whether extending prophylaxis with oral valganciclovir from the standard 3 months to 12 months after lung transplantation is efficacious.Design: Randomized, clinical trial. Patients were randomly assigned by a central automated system to treatment or placebo. Patients and investigators were blinded to treatment status. (ClinicalTrials.gov registration number: NCT00227370)Setting: Multicenter trial involving 11 U.S. lung transplant centers.Patients: 136 lung transplant recipients who completed 3 months of valganciclovir prophylaxis.Intervention: 9 additional months of oral valganciclovir (n = 70) or placebo (n = 66).Measurements: The primary end point was freedom from CMV disease (syndrome or tissue-invasive) on an intention-to-treat basis 300 days after randomization. Secondary end points were CMV disease severity, CMV infection, acute rejection, opportunistic infections, ganciclovir resistance, and safety.Results: CMV disease occurred in 32% of the short-course group versus 4% of the extended-course group (P < 0.001). Significant reductions were observed with CMV infection (64% vs. 10%; P < 0.001) and disease severity (110 000 vs. 3200 copies/mL, P = 0.009) with extended treatment. Rates of acute rejection, opportunistic infections, adverse events, CMV UL97 ganciclovir-resistance mutations, and laboratory abnormalities were similar between groups. During the 6 months after study completion, a low incidence of CMV disease was observed in both groups.Limitation: Longer-term effects of extended prophylaxis were not assessed.Conclusion: In adult lung transplant recipients who have received 3 months of valganciclovir, extending prophylaxis by an additional 9 months significantly reduces CMV infection, disease, and disease severity without increased ganciclovir resistance or toxicity. A beneficial effect with regard to prevention of CMV disease seems to extend at least through 18 months after transplantation. [ABSTRACT FROM AUTHOR]- Published
- 2010
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6. The SPINK1 N34S mutation is not associated with Type 2 diabetes mellitus in a population of the USA.
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Schneider A, Lawrence EC, Barmada MM, Norris JM, Hamman RF, Marshall JA, Ferrell RE, and Whitcomb DC
- Abstract
AIMS: Mutations in the serine protease inhibitor (SPINK1) gene have been associated with all forms of chronic pancreatitis. Recently, an association of SPINK1 mutations with early-onset Type 2 diabetes mellitus has been reported in patients from Bangladesh. Therefore, we determined the frequency of SPINK1 N34S mutations in patients with Type 2 diabetes mellitus from the USA. METHODS: The study population of Hispanic and non-Hispanic white people consisted of 387 patients with Type 2 diabetes and familial clustering of the disease, 232 family members without diabetes, 259 patients with Type 2 diabetes without a family history, and 302 ethnically matched healthy controls as part of the San Luis Valley Diabetes Study. We performed linkage- and association-analysis in 82 multiplex families with Type 2 diabetes mellitus. RESULTS: No significant linkage or allele sharing was detected between Type 2 diabetes mellitus and the SPINK1 locus. The frequency of the N34S mutation was determined by fluorescence polarization and was similar between patients (n = 14/387 patients with familial clustering; n = 2/259 patients without family history) and controls (n = 5/232 family members without diabetes; n = 10/302 individuals). Variables such as ethnicity, age of diabetes onset and percentage of individuals with impaired glucose tolerance did not differ significantly between carriers and homozygous normal individuals. CONCLUSION: The SPINK1 N34S mutation appears not to predispose Hispanic or non-Hispanic white people from the USA to the development of Type 2 diabetes mellitus. [ABSTRACT FROM AUTHOR]
- Published
- 2005
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7. Heart rate variability is associated with polymorphic variation in the choline transporter gene.
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Neuman SA, Lawrence EC, Jennings JR, Ferrell RE, and Manuck SB
- Published
- 2005
8. In vitro cytotoxicity of chrysotile asbestos to human pulmonary alveolar macrophages is decreased by organosilane coating and surfactant
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M. V. Marshall, David L. Busbee, Lawrence Ec, Feuerbacher Dg, Myles L. Mace, A. C. Griffin, Morrison Dg, and Theodore L. McLemore
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Adult ,Male ,Pathology ,medicine.medical_specialty ,food.ingredient ,Asbestos, Serpentine ,Health, Toxicology and Mutagenesis ,In vitro cytotoxicity ,Pharmacology toxicology ,In Vitro Techniques ,Toxicology ,medicine.disease_cause ,Lecithin ,Asbestos ,Surface-Active Agents ,food ,Pulmonary surfactant ,Chrysotile ,medicine ,Humans ,Cytotoxic T cell ,Mutagenicity Tests ,Chemistry ,Macrophages ,technology, industry, and agriculture ,Cell Biology ,respiratory system ,V79 cells ,Molecular biology ,Pulmonary Alveoli ,Female - Abstract
Human pulmonary alveolar macrophages were used to quantitate the cytotoxic effect of surface-altered chrysotile asbestos. Little difference was observed in mortality between chrysotile asbestos that was surface-treated to a 42% extent by a hydrophobic organosilane or untreated chrysotile. Little or no effect on mortality was observed when human pulmonary alveolar macrophages were cultured with untreated chrysotile or acid-leached asbestos in the presence of 10 mM dipalmitoyl lecithin. However, when human pulmonary alveolar macrophages were cultured with a hydrophobically-treated (to a 42% or 95% extent) chrysotile asbestos in the presence of 10 mM dipalmitoyl lecithin, a statistically significant decrease in mortality was observed compared to untreated chrysotile. No mutagenic activity was observed when V79 cells were cultured with acid-leached, or 42% hydrophobically-treated chrysotile asbestos, even when human pulmonary alveolar macrophages were included as an activation source. The 95% hydrophobically-treated and acid-leached chrysotile also exhibited decreased binding of benzo[a]pyrene compared to untreated chrysotile asbestos.
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- 1986
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9. Evolution of a lymphoma with helper T cell characteristics in Sezary syndrome
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Lawrence, EC, Broder, S, Jaffe, ES, Braylan, RC, Dobbins, WO, Young, RC, and Waldmann, TA
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- 1978
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10. SIRT1-dependent myoprotective effects of resveratrol on muscle injury induced by compression
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Thomas eSin, Benjamin eYung, Shea eYip, Lawrence eChan, Cesar eWong, Eric eTam, and Parco M Siu
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Pressure Ulcer ,skeletal muscle ,resveratrol ,SIRT1 ,Compression injury ,Physiology ,QP1-981 - Abstract
Our current understanding on the molecular mechanisms by which sustained compression induces skeletal muscle injury is very limited. This study aimed to test the hypothesis that activation of SIRT1 by the natural antioxidant resveratrol could deactivate apoptotic and catabolic signalling in skeletal muscle exposed to moderate compression. Two cycles of 6-hour constant pressure at 100 mmHg was applied to the tibialis region of right, but not left hindlimbs of Sprague Dawley rats pre-treated with DMSO (vehicle control) or resveratrol with/without sirtinol. Skeletal muscle tissues lying underneath and spatially corresponding to the compressed sites were collected for analyses. Resveratrol prevented the compression-induced manifestations of pathohistological damages including elevations of the number of interstitial nuclei and area of interstitial space and ameliorated oxidative damages measured as 4-hydroxy-2-nonenal (4HNE) and nitrotyrosine in skeletal muscle. In parallel, resveratrol augmented the expression level and activity of SIRT1 and phosphorylation levels of Foxo3a and Akt while suppressed the increases in protein abundances of p53, Bax, MAFbx and ubiquitin, enzymatic activities of caspase 3 and 20S proteasome, and apoptotic DNA fragmentation in the compressed muscle. These favourable myoprotective effects of resveratrol were diminished upon pharmacological blockade of SIRT1 by using sirtinol. These novel data support the hypothesis that the anti-apoptotic and anti-catabolic effects of resveratrol on compression injury in skeletal muscle required the action of SIRT1.
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- 2015
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11. Alteration of in vitro immunoglobulin secretion by amosite asbestos
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Lawrence, EC, primary
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- 1983
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12. Antitumor activity and hydrogen peroxide release by macrophages elicited by trehalose diesters
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Lepoivre, M, primary, Tenu, JP, additional, Lemaire, G, additional, Petit, JF, additional, Lawrence, EC, additional, McClune, HW, additional, Wilson, RK, additional, Key, MM, additional, Dodson, RM, additional, and Hurst, GA, additional
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- 1983
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13. Nuclear Factor kappa B is required for the production of infectious human herpesvirus 8 virions
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Negin N Blattman, Michael eLagunoff, and Lawrence eCorey
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KSHV ,hf ,NFκB ,HHV8 ,MVEC ,BCBL-1 ,Microbiology ,QR1-502 - Abstract
Human herpesvirus 8 (HHV8) infection leads to potent activation of nuclear factor kappa B (NFB) in primary and transformed cells. We used recombinant HHV8 (rKSHV.219) expressing green fluorescent protein under the constitutive cellular promoter elongation factor 2 and red fluorescent protein under an early HHV8 lytic gene promoter T1.1, to monitor replication during infection of human foreskin fibroblasts (HF), noting changes in NFB activity. In primary HF, NFB levels do not affect HHV8 ability to establish infection or maintain latency. Furthermore, there was no effect on the percent of cells undergoing reactivation from latency, and there were similar numbers of released and cell associated HHV8 viral particles following reactivation in the presence of inhibitors. Reactivation of HHV8 in latently infected HF in the presence of NFB inhibitors resulted in production of viral particles that did not efficiently establish infection, due to deficiencies in binding and/or entry into normally permissive cells. Exogenous expression of glycoprotein M, an envelope protein involved in viral binding and entry was able to partially overcome the deficiency induced by NFB inhibitors. Our data indicate that in primary cells, NFB is not required for infection, establishment of latency, or entry into the lytic cycle, but is required for the expression of virion associated genes involved in the initial steps of virion infectivity. These studies suggest that strategies to inhibit NFB may prevent HHV8 spread and should be considered as a potential therapeutic target for preventing HHV8 associated diseases.
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- 2014
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14. Book reviews.
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Waters DB, Allen CW, and Lawrence EC
- Published
- 2008
15. A Guiding Model for Undergraduate Medical Education Well-Being Programs.
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Lawrence EC, Sheridan C, Hurtado A, Lee WW, Lizotte-Waniewski M, Rea M, and Zehle C
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- Humans, United States, Curriculum, Mental Health, Resilience, Psychological, Schools, Medical organization & administration, Education, Medical, Undergraduate methods, Education, Medical, Undergraduate organization & administration, Students, Medical psychology
- Abstract
Abstract: Most medical schools have instituted undergraduate medical education (UME) well-being programs in recent years in response to high rates of medical student distress, but there is currently significant variability in the structure of UME well-being programs and limited guidance on how to best structure such programs to achieve success. In this article, the authors, all leaders of medical student well-being programs at their home institutions and members of the Association of American Medical Colleges Group on Student Affairs Committee on Student Affairs Working Group on Medical Student Well-Being between 2019 and 2023 offer guidance to the national community on how best to structure a UME well-being program. They use the current literature and their professional experiences leading well-being efforts at 7 different institutions to review the case for addressing medical student well-being, propose a guiding model, and make recommendations for strategies to implement this model.The proposed guiding model emphasizes the importance of the learning environment and efficiency of learning to medical student well-being, as well as personal resilience. Based on this model, the authors recommend specific and tangible well-being strategies to implement systemic interventions to improve the learning environment, efficiency of learning, and personal resilience, including formalizing the well-being program; hiring qualified, dedicated, and empowered well-being leadership with clear responsibilities; acting as a central hub for resources and as a liaison with mental health care; and establishing robust program evaluation methods., (Copyright © 2024 the Association of American Medical Colleges.)
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- 2024
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16. Navigating Minority and Gender Discrimination, Substance Use Disorder, Financial Distress, and Workplace Politics: Lessons for Work-Life Wellness in Academic Medicine: Part 2 of 3.
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Ahmed R, Hartwell JL, Farley H, MacRae J, Rogers DA, Lawrence EC, Brazeau CM, Park EM, Cassidy A, Hartsock J, Holmes E, Schroeder K, and Barach P
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- 2023
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17. Occupational Health Risks of Practicing Medicine.
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Lawrence EC
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- Humans, Medicine, Occupational Health
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- 2021
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18. Requiring the Healer's Art Curriculum to Promote Professional Identity Formation Among Medical Students.
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Lawrence EC, Carvour ML, Camarata C, Andarsio E, and Rabow MW
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- Curriculum, Empathy, Humanism, Humans, Mexico, Education, Medical, Undergraduate, Students, Medical
- Abstract
The Healer's Art curriculum (HART) is one of the best-known educational strategies to support medical student professional identity formation. HART has been widely used as an elective curriculum. We evaluated students' experience with HART when the curriculum was required. All one hundred eleven members of the class of 2019 University of New Mexico School of Medicine students were required to enroll in HART. We surveyed the students before and after the course to assess its self-reported impact on key elements of professional identity formation such as empathy towards patients and peers, commitment to service, and burnout. A majority of students (n=53 of 92, 57.6%) reported positive effects of the course on their empathy towards other students. This finding was significantly associated with self-reported willingness to have elected the course had it not been required. One-half of respondents (n=46 of 92, 50.0%) reported positive effects on their empathy towards future patients. At least one-quarter to one-third of respondents reported positive influences on commitment to service, conceptions about being a physician, and self-perceived burnout. Students report benefits on their professional identity formation after participating in a required course on humanism. Empathy-building among peers is one valuable outcome of such curricula.
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- 2020
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19. Organizational strategies to reduce physician burnout and improve professional fulfillment.
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Olson K, Marchalik D, Farley H, Dean SM, Lawrence EC, Hamidi MS, Rowe S, McCool JM, O'Donovan CA, Micek MA, and Stewart MT
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- Humans, Organizational Culture, Burnout, Professional prevention & control, Humanism, Job Satisfaction, Motivation, Physicians psychology
- Abstract
Burnout is highly prevalent among physicians and has been associated with negative outcomes for physicians, patients, staff, and health-care organizations. Reducing physician burnout and increasing physician well-being is a priority. Systematic reviews suggest that organization-based interventions are more effective in reducing physician burnout than interventions targeted at individual physicians. This consensus review by leaders in the field across multiple institutions presents emerging trends and exemplary evidence-based strategies to improve professional fulfillment and reduce physician burnout using Stanford's tripartite model of physician professional fulfillment as an organizing framework: practice efficiency, culture, and personal resilience to support physician well-being. These strategies include leadership traits, latitude of control and autonomy, collegiality, diversity, teamwork, top-of-license workflows, electronic health record (EHR) usability, peer support, confidential mental health services, work-life integration and reducing barriers to practicing a healthy lifestyle. The review concludes with evidence-based recommendations on establishing an effective physician wellness program., (Copyright © 2019 Elsevier Inc. All rights reserved.)
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- 2019
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20. Dyadic connections in the context of group mentoring: A social network approach.
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Williams JL, Molloy Elreda L, Henderson LJ, Deutsch NL, and Lawrence EC
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- Adolescent, Adult, Female, Humans, Students, Universities, Young Adult, Group Processes, Interpersonal Relations, Mentoring, Social Networking
- Abstract
Aims: The aim of this study was to examine how relational ties among all participants in a group mentoring program related to connections within assigned mentor-mentee dyads., Methods: College student female mentors (n = 54) and middle school-aged female mentees ( n = 65) in eight mentoring groups completed social network surveys on multiple occasions, rating all groupmates on connection and effort to reach out., Results: Hierarchical linear models (participants nested in groups) revealed mentors who were rated as being highly connected to multiple mentees had stronger connections within their dyad. For mentees, high ratings on efforts to reach out to others related to the stronger dyadic connection. Mentees reported lower dyadic connection in groups with more segregation by role., Conclusion: Results suggest group dynamics matter for one-on-one mentoring relationships, but how they matter differs by role. Implications for the use of social network analysis to assess complex settings are discussed., (© 2019 Wiley Periodicals, Inc.)
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- 2019
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21. Analysis of the Omaha System Prototype Icons for Health Literacy: A Global Survey.
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Kang YJ, Monsen KA, Martinson BE, Stromme AE, Weirich EG, Schneider RN, Lawrence EC, Maki TA, Seebold C, and Martin KS
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- 2017
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22. Adaptation of Lean Six Sigma Methodologies for the Evaluation of Veterans Choice Program at 3 Urban Veterans Affairs Medical Centers.
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Ball SL, Stevenson LD, Ladebue AC, McCreight MS, Lawrence EC, Oestreich T, and Lambert-Kerzner AC
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- Program Evaluation, United States, United States Department of Veterans Affairs, Choice Behavior, Hospitals, Urban, Hospitals, Veterans standards, Quality Improvement, Total Quality Management methods
- Abstract
Objective: The Veterans Health Administration (VHA) is adapting to meet the changing needs of our Veterans. VHA leaders are promoting quality improvement strategies including Lean Six Sigma (LSS). This study used LSS tools to evaluate the Veterans Choice Program (VCP), a program that aims to improve access to health care services for eligible Veterans by expanding health care options to non-VHA providers., Research Design: LSS was utilized to assess the current process and efficiency patterns of the VCP at 3 VHA Medical Centers. LSS techniques were used to assess data obtained through semistructured interviews with Veterans, staff, and providers to describe and evaluate the VCP process by identifying wastes and defects., Results: The LSS methodology facilitated the process of targeting priorities for improvement and constructing suggestions to close identified gaps and inefficiencies. Identified key process wastes included inefficient exchange of clinical information between stakeholders in and outside of the VHA; poor dissemination of VCP programmatic information; shortages of VCP-participating providers; duplication of appointments; declines in care coordination; and lack of program adaptability to local processes. Recommendations for improvement were formulated using LSS., Conclusions: This evaluation illustrates how LSS can be utilized to assess a nationally mandated health care program. By focusing on stakeholder, staff, and Veteran perspectives, process defects in the VCP were identified and improvement recommendations were made. However, the current LSS language used is not intuitive in health care and similar applications of LSS may consider using new language and goals adapted specifically for health care.
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- 2017
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23. The culture of mentoring: Ethnocultural empathy and ethnic identity in mentoring for minority girls.
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Peifer JS, Lawrence EC, Williams JL, and Leyton-Armakan J
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- Adolescent, Adult, Child, Female, Humans, Interpersonal Relations, Interprofessional Relations, Students psychology, United States ethnology, Young Adult, Empathy physiology, Ethnicity psychology, Mentoring methods, Mentors psychology, Minority Groups education, Social Identification
- Abstract
Objectives: Many mentoring programs place minority group mentees with majority group mentors. These programs aim to promote beneficial outcomes for their diverse participants. The present study explores mentors of color and White mentors' ethnocultural empathy and ethnic identities in association with their minority group mentees' ethnic identities., Method: Our study examined 95 mentoring pairs of middle school girls of color and college student women from both majority and minority group cultural backgrounds., Results: A series of linear regressions revealed an association between mentors' ethnocultural empathy and EI exploration/commitment and minority group mentees' ethnic identity exploration, regardless of the mentors' majority group status., Conclusions: The results of this preliminary study suggest that mentors' cultural identity and empathy may be linked with mentees' willingness to explore their own ethnic identities. We discuss the implications for mentoring programs that seek to build participants' ethnic identities and ethnocultural empathy. (PsycINFO Database Record, ((c) 2016 APA, all rights reserved).)
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- 2016
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24. Latent transforming growth factor binding protein 4 regulates transforming growth factor beta receptor stability.
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Su CT, Huang JW, Chiang CK, Lawrence EC, Levine KL, Dabovic B, Jung C, Davis EC, Madan-Khetarpal S, and Urban Z
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- Animals, Case-Control Studies, Cells, Cultured, Disease Models, Animal, Down-Regulation, Endocytosis genetics, Female, Fibroblasts cytology, Fibroblasts metabolism, Humans, Immunoprecipitation, Latent TGF-beta Binding Proteins genetics, Male, Mice, Mice, Knockout, Mutation, Phosphorylation, Protein Serine-Threonine Kinases genetics, Receptor, Transforming Growth Factor-beta Type I, Receptor, Transforming Growth Factor-beta Type II, Receptors, Transforming Growth Factor beta genetics, Signal Transduction, Smad2 Protein genetics, Smad2 Protein metabolism, Cutis Laxa genetics, Latent TGF-beta Binding Proteins metabolism, Protein Serine-Threonine Kinases metabolism, Receptors, Transforming Growth Factor beta metabolism
- Abstract
Mutations in the gene for the latent transforming growth factor beta binding protein 4 (LTBP4) cause autosomal recessive cutis laxa type 1C. To understand the molecular disease mechanisms of this disease, we investigated the impact of LTBP4 loss on transforming growth factor beta (TGFβ) signaling. Despite elevated extracellular TGFβ activity, downstream signaling molecules of the TGFβ pathway, including pSMAD2 and pERK, were down-regulated in LTBP4 mutant human dermal fibroblasts. In addition, TGFβ receptors 1 and 2 (TGFBR1 and TGFBR2) were reduced at the protein but not at the ribonucleic acid level. Treatment with exogenous TGFβ1 led to an initially rapid increase in SMAD2 phosphorylation followed by a sustained depression of phosphorylation and receptor abundance. In mutant cells TGFBR1 was co-localized with lysosomes. Treatment with a TGFBR1 kinase inhibitor, endocytosis inhibitors or a lysosome inhibitor, normalized the levels of TGFBR1 and TGFBR2. Co-immunoprecipitation demonstrated a molecular interaction between LTBP4 and TGFBR2. Knockdown of LTBP4 reduced TGFβ receptor abundance and signaling in normal cells and supplementation of recombinant LTBP4 enhanced these measures in mutant cells. In a mouse model of Ltbp4 deficiency, reduced TGFβ signaling and receptor levels were normalized upon TGFBR1 kinase inhibitor treatment. Our results show that LTBP4 interacts with TGFBR2 and stabilizes TGFβ receptors by preventing their endocytosis and lysosomal degradation in a ligand-dependent and receptor kinase activity-dependent manner. These findings identify LTBP4 as a key molecule required for the stability of the TGFβ receptor complex, and a new mechanism by which the extracellular matrix regulates cytokine receptor signaling., (© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)
- Published
- 2015
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25. A novel elastin gene mutation in a Vietnamese patient with cutis laxa.
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Siefring ML, Lawrence EC, Nguyen TC, Lu D, Pham G, Lorenchick C, Levine KL, and Urban Z
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- Child, Preschool, Family Health, Female, Heterozygote, Humans, Parents, Vietnam, Asian People genetics, Cutis Laxa genetics, Cutis Laxa pathology, Elastin genetics, Point Mutation
- Abstract
We report a 3-year-old girl from Vietnam with severe congenital cutis laxa; no cardiovascular, pulmonary, neurologic, or visceral involvement; and no family history of cutis laxa. Mutational analysis of the elastin gene identified heterozygosity for a previously unreported de novo c.2184delT mutation in exon 30 not present in either parent., (© 2014 Wiley Periodicals, Inc.)
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- 2014
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26. Connexin 47 mutations increase risk for secondary lymphedema following breast cancer treatment.
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Finegold DN, Baty CJ, Knickelbein KZ, Perschke S, Noon SE, Campbell D, Karlsson JM, Huang D, Kimak MA, Lawrence EC, Feingold E, Meriney SD, Brufsky AM, and Ferrell RE
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- Adult, Aged, Aged, 80 and over, Base Sequence, Breast Neoplasms drug therapy, Breast Neoplasms pathology, Breast Neoplasms surgery, Case-Control Studies, Cell Line, Tumor, Female, Genetic Predisposition to Disease, HeLa Cells, Humans, Lymphedema drug therapy, Middle Aged, Risk Factors, Sequence Analysis, DNA, Young Adult, Breast Neoplasms genetics, Connexins genetics, Lymphedema genetics
- Abstract
Purpose: Secondary lymphedema is a frequent complication of breast cancer associated with surgery, chemotherapy, or radiation following breast cancer treatment. The potential contribution of genetic susceptibility to risk of developing secondary lymphedema following surgical trauma, radiation, and other tissue insults has not been studied., Experimental Design: To determine whether women with breast cancer and secondary lymphedema had mutations in candidate lymphedema genes, we undertook a case-control study of 188 women diagnosed with breast cancer recruited from the University of Pittsburgh Breast Cancer Program (http://www.upmccancercenter.com/breast/index.cfm) between 2000 and 2010. Candidate lymphedema genes, GJC2 (encoding connexin 47 [Cx47]), FOXC2, HGF, MET, and FLT4 (encoding VEGFR3), were sequenced for mutation. Bioinformatics analysis and in vitro functional assays were used to confirm significance of novel mutations., Results: Cx47 mutations were identified in individuals having secondary lymphedema following breast cancer treatment but not in breast cancer controls or normal women without breast cancer. These novel mutations are dysfunctional as assessed through in vitro assays and bioinformatics analysis and provide evidence that altered gap junction function leads to lymphedema., Conclusions: Our findings challenge the view that secondary lymphedema is solely due to mechanical trauma and support the hypothesis that genetic susceptibility is an important risk factor for secondary lymphedema. A priori recognition of genetic risk (i) raises the potential for early detection and intervention for a high-risk group and (ii) allows the possibility of altering surgical approach and/or chemo- and radiation therapy, or direct medical treatment of secondary lymphedema with novel connexin-modifying drugs., (©2012 AACR.)
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- 2012
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27. Cumulative exposure to gamma interferon-dependent chemokines CXCL9 and CXCL10 correlates with worse outcome after lung transplant.
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Neujahr DC, Perez SD, Mohammed A, Ulukpo O, Lawrence EC, Fernandez F, Pickens A, Force SD, Song M, Larsen CP, and Kirk AD
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- Adolescent, Adult, Aged, Bronchiolitis Obliterans metabolism, Bronchoalveolar Lavage Fluid chemistry, Disease Progression, Enzyme-Linked Immunosorbent Assay, Female, Follow-Up Studies, Humans, Male, Middle Aged, Postoperative Period, Prognosis, Prospective Studies, Young Adult, Bronchiolitis Obliterans surgery, Chemokine CXCL10 metabolism, Chemokine CXCL9 metabolism, Graft Rejection metabolism, Graft Survival, Interferon-gamma metabolism, Lung Transplantation
- Abstract
Outcomes following lung transplant are suboptimal owing to chronic allograft failure termed bronchiolitis obliterans syndrome (BOS). Prior work in both mice and humans has shown that interferon gamma (IFNG)-induced chemokines, including CXCL9 and CXCL10, are elevated in patients with established BOS. We hypothesized that patients who ultimately developed BOS would have elevations in these chemokines before losing lung function. We utilized a high throughput multiplex enzyme-linked immunosorbent assay (ELISA) to measure biomarkers in bronchoalveolar lavage fluid (BALF). We modeled cumulative exposure to seven biomarkers (CXCL9, CXCL10, RANTES, IL1-RA, IL-17, MCP1 and IL-13) by calculating the 1-year area under the curve (AUC) for each biomarker in the BALF of 40 lung transplant patients who had at least four samples obtained in the first year posttransplant. Cumulative elevations in CXCL9 and CXCL10 were associated with a significant risk of subsequent graft failure after transplant (HR 9.37 and 5.52, respectively; p < 0.01 for both). Further these chemokines were also elevated in patients before the onset of BOS. CXCL9 and CXCL10 elevations were seen between 3 and 9 months before graft failure. Our data show that persistent presence of CXCL9 and CXCL10 portents worsening lung allograft function; measuring these IFNG-induced chemokines might prospectively identify patients at risk for BOS., (© 2011 The American Society of Transplantation and the American Society of Transplant Surgeons.)
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- 2012
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28. Polymorphic variation in choline transporter gene (CHT1) is associated with early, subclinical measures of carotid atherosclerosis in humans.
- Author
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Neumann SA, Linder KJ, Muldoon MF, Sutton-Tyrrell K, Kline C, Shrader CJ, Lawrence EC, Ferrell RE, and Manuck SB
- Subjects
- Adult, Asymptomatic Diseases, Carotid Artery Diseases ethnology, Female, Gene Frequency, Genetic Predisposition to Disease, Humans, Logistic Models, Male, Middle Aged, Odds Ratio, Pennsylvania epidemiology, Phenotype, Predictive Value of Tests, Risk Assessment, Risk Factors, White People genetics, Carotid Artery Diseases diagnostic imaging, Carotid Artery Diseases genetics, Carotid Artery, Common diagnostic imaging, Carotid Intima-Media Thickness, Polymorphism, Genetic, Symporters genetics
- Abstract
Atherosclerosis is a heritable trait with little known about specific genetic influences on preclinical measures of plaque formation. Based on relations of parasympathetic-cholinergic function to atherosclerosis and to a choline transporter gene [CHT1 (G/T)] polymorphism, we investigated whether the same allelic variant predicts variation in carotid intima-media thickness (IMT) and plaque formation. Carotid IMT and plaque occurrence as well as genotyping for the CHT1 (G/T) variant were measured in a sample (N = 264) of generally healthy adults (age 30-55) of European ancestry. CHT1 GG homozygotes had greater IMT (P < 0.005) and plaque occurrence (P < 0.020) than T allele carriers. This is the first study showing polymorphic variation in the CHT1 gene to predict early, subclinical measures of carotid atherosclerosis which may aid in understanding cholinergic-vagal processes potentially underlying atherosclerotic risk.
- Published
- 2012
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29. Cumulative exposure to CD8+ granzyme Bhi T cells is associated with reduced lung function early after lung transplantation.
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Mohammed A, Ulukpo O, Lawrence EC, Fernandez F, Pickens A, Gal AA, Force SD, Easley KC, Larsen CP, Kirk AD, and Neujahr DC
- Subjects
- Area Under Curve, Biomarkers metabolism, Bronchoalveolar Lavage Fluid immunology, Bronchoscopy, CD8-Positive T-Lymphocytes immunology, Female, Forced Expiratory Volume, Georgia, Graft Rejection immunology, Graft Rejection physiopathology, Granzymes blood, Humans, Least-Squares Analysis, Lung immunology, Lung physiopathology, Lung Transplantation adverse effects, Male, Middle Aged, Spirometry, Time Factors, Treatment Outcome, CD8-Positive T-Lymphocytes enzymology, Graft Rejection enzymology, Granzymes metabolism, Lung enzymology, Lung Transplantation immunology
- Abstract
Outcomes following lung transplant remain suboptimal. This is attributable to variable posttransplant recovery of lung function, and inconsistent degrees of lung function loss after peak function is reached. Granzyme B is elevated in the blood and bronchoalveolar lavage (BAL) in acute rejection. We hypothesized that persistent exposure to T cells high in granzyme B would negatively correlate with lung function. We investigated cumulative exposure measured as the area-under-the-curve (AUC) of CD8+ T cell granzyme Bhi cells in the first year posttransplant in both BAL and blood in 24 transplant recipients. We assessed the correlation between cumulative 1-year exposure and FEV1 slope. There was a negative correlation between 1-year exposure and FEV1 slope within the first year (r=-0.63; P=.001). This relationship persisted even when adjusted for transplant type, gender, age, rejection, and indication for transplantation. In contrast, no relationship was seen with the 1-year AUC and lung function after 1 year posttransplant. In contrast to the BAL granzyme Bhi levels, granzyme Bhi levels from the blood showed no relationship with lung function. These findings suggest that CD8+ T-cell-driven factors are responsible for early improvements in lung function after transplantation., (Copyright © 2011 Elsevier Inc. All rights reserved.)
- Published
- 2011
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30. Gastroesophageal reflux disease is associated with an increased rate of acute rejection in lung transplant allografts.
- Author
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Shah N, Force SD, Mitchell PO, Lin E, Lawrence EC, Easley K, Qian J, Ramirez A, Neujahr DC, Gal A, Leeper K, and Pelaez A
- Subjects
- Acute Disease, Adult, Aged, Cytomegalovirus Infections epidemiology, Female, Gastric Fundus pathology, Gastroesophageal Reflux epidemiology, Humans, Immunosuppressive Agents therapeutic use, Lung Diseases classification, Lung Diseases surgery, Lung Transplantation immunology, Male, Middle Aged, Retrospective Studies, Transplantation, Homologous, Gastroesophageal Reflux etiology, Graft Rejection epidemiology, Lung Transplantation adverse effects
- Abstract
Purpose: Gastric fundoplication (GF) for gastroesophageal reflux disease (GERD) may protect against the progression of chronic rejection in lung transplant (LT) recipients. However, the association of GERD with acute rejection episodes (ARE) is uncertain. This study sought to identify if ARE were linked to GERD in LT patients., Methods: This single-center retrospective observational study, of patients transplanted from January 1, 2000, to January 31, 2009, correlated results of pH probe testing for GERD with ARE (≥International Society for Heart and Lung Transplantation A1 or B1). We compared the rates of ARE among patients with GERD (DeMeester Score > 14.7) versus without GERD as number of ARE per 1,000 patient-days after LT. Patients undergoing GF prior to LT were excluded., Results: The analysis included 60 LT subjects and 9,249 patient-days: 33 with GERD versus 27 without GERD. We observed 51 ARE among 60 LT recipients. The rate of ARE was highest among patients with GERD: 8.49 versus 2.58, an incidence density ratio (IDR) of 3.29 (P = .00016). Upon multivariate negative binomial regression modeling, only GERD was associated with ARE (IDR 2.15; P = .009). Furthermore, GERD was associated with multiple ARE (36.4% vs 0%; P < .0001) and earlier onset compared with patients without GERD: ARE proportion at 2 months was 0.55 versus 0.26 P = .004)., Conclusion: In LT recipients, GERD was associated with a higher rate, multiple events, and earlier onset of ARE. The efficacy of GF to reduce ARE among patients with GERD needs further evaluation., (2010 Elsevier Inc. All rights reserved.)
- Published
- 2010
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31. The relationship of marital status and clinical characteristics in middle-aged and older patients with schizophrenia and depressive symptoms.
- Author
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Nyer M, Kasckow J, Fellows I, Lawrence EC, Golshan S, Solorzano E, and Zisook S
- Subjects
- Adult, Age Factors, Aged, Depressive Disorder psychology, Female, Humans, Male, Middle Aged, Personality Inventory, Psychiatric Status Rating Scales, Psychotic Disorders psychology, Quality of Life, Single Person psychology, Social Adjustment, Socioeconomic Factors, Statistics as Topic, Suicidal Ideation, United States, Depressive Disorder diagnosis, Depressive Disorder epidemiology, Marital Status, Psychotic Disorders diagnosis, Psychotic Disorders epidemiology, Schizophrenia diagnosis, Schizophrenia epidemiology, Schizophrenic Psychology
- Abstract
Background: This study examines the relationship of marital status to depression, positive and negative symptoms, quality of life, and suicidal ideation among 211 patients with schizophrenia-spectrum disorders and subsyndromal depressive symptoms. We hypothesized that single participants would have more severe symptomatology than married and cohabitating participants., Methods: Outpatients, age 40 or older, were diagnosed with schizophrenia or schizoaffective disorders using the MINI Structured Clinical Interview for DSM-IV Axis 1 Disorders. Participants exhibited a score of >8 on the Hamilton Rating Scale for Depression but did not meet criteria for a major depressive episode., Results: Participants who were married or cohabitating had a later age of onset of first psychotic episode or hospitalization than those who were single (age, 29.35 vs 24.21). Married participants rated their quality of life higher than those who were single (mean Quality of Life Scale scores, 72.28 vs 53.87) and had less suicidal ideation than those who were divorced, widowed, or separated (7.4% vs 29.2%)., Conclusions: In middle-aged and older individuals with schizophrenia or schizoaffective disorder and depressive symptoms, marriage appeared to enhance quality of life and protect against suicidal ideation. Efforts that focus on providing additional support for those who are experiencing divorce or separation could prove to be lifesaving for these individuals.
- Published
- 2010
32. GJC2 missense mutations cause human lymphedema.
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Ferrell RE, Baty CJ, Kimak MA, Karlsson JM, Lawrence EC, Franke-Snyder M, Meriney SD, Feingold E, and Finegold DN
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Amino Acid Sequence, Base Sequence, Child, Child, Preschool, Female, Humans, Male, Middle Aged, Models, Molecular, Molecular Sequence Data, Pedigree, Sequence Alignment, Connexins genetics, Lymphedema genetics, Mutation, Missense
- Abstract
Lymphedema is the clinical manifestation of defects in lymphatic structure or function. Mutations identified in genes regulating lymphatic development result in inherited lymphedema. No mutations have yet been identified in genes mediating lymphatic function that result in inherited lymphedema. Survey microarray studies comparing lymphatic and blood endothelial cells identified expression of several connexins in lymphatic endothelial cells. Additionally, gap junctions are implicated in maintaining lymphatic flow. By sequencing GJA1, GJA4, and GJC2 in a group of families with dominantly inherited lymphedema, we identified six probands with unique missense mutations in GJC2 (encoding connexin [Cx] 47). Two larger families cosegregate lymphedema and GJC2 mutation (LOD score = 6.5). We hypothesize that missense mutations in GJC2 alter gap junction function and disrupt lymphatic flow. Until now, GJC2 mutations were only thought to cause dysmyelination, with primary expression of Cx47 limited to the central nervous system. The identification of GJC2 mutations as a cause of primary lymphedema raises the possibility of novel gap-junction-modifying agents as potential therapy for some forms of lymphedema., (Copyright 2010 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.)
- Published
- 2010
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33. Receptor for advanced glycation end products in donor lungs is associated with primary graft dysfunction after lung transplantation.
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Pelaez A, Force SD, Gal AA, Neujahr DC, Ramirez AM, Naik PM, Quintero DA, Pileggi AV, Easley KA, Echeverry R, Lawrence EC, Guidot DM, and Mitchell PO
- Subjects
- Biopsy, Humans, Receptor for Advanced Glycation End Products, Graft Rejection, Lung Transplantation, Receptors, Immunologic metabolism, Tissue Donors
- Abstract
Development of primary graft dysfunction (PGD) is associated with poor outcomes after transplantation. We hypothesized that Receptor for Advanced Glycation End-products (RAGE) levels in donor lungs is associated with the development of PGD. Furthermore, we hypothesized that RAGE levels would be increased with PGD in recipients after transplantation. We measured RAGE in bronchoalveolar lavage fluid (BALf) from 25 donors and 34 recipients. RAGE was also detected in biopsies (transbronchial biopsy) from recipients with and without PGD. RAGE levels were significantly higher in donor lungs that subsequently developed sustained PGD versus transplanted lungs that did not display PGD. Donor RAGE level was a predictor of recipient PGD (odds ratio = 1.768 per 0.25 ng/mL increase in donor RAGE level). In addition, RAGE levels remained high for 14 days in those recipients that developed severe graft dysfunction. Recipients may be at higher risk for developing PGD if they receive transplanted organs that have higher levels of soluble RAGE prior to explantation. Moreover, the clinical and pathologic abnormalities associated with PGD posttransplantation are associated with increased RAGE expression. These findings also raise the possibility that targeting the RAGE signaling pathway could be a novel strategy for treatment and/or prevention of PGD.
- Published
- 2010
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34. Dynamics of human regulatory T cells in lung lavages of lung transplant recipients.
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Neujahr DC, Cardona AC, Ulukpo O, Rigby M, Pelaez A, Ramirez A, Gal AA, Force SD, Lawrence EC, Kirk AD, and Larsen CP
- Subjects
- Acute Disease, Adolescent, Adult, Aged, Bronchoalveolar Lavage Fluid cytology, Bronchoalveolar Lavage Fluid immunology, Female, Forkhead Transcription Factors metabolism, Graft Rejection immunology, Graft Rejection metabolism, Graft Rejection pathology, Humans, Longitudinal Studies, Lung immunology, Lung pathology, Lung Transplantation pathology, Lung Transplantation physiology, Male, Middle Aged, T-Lymphocytes, Regulatory metabolism, Young Adult, Lung Transplantation immunology, T-Lymphocytes, Regulatory immunology
- Abstract
Background: Despite advances in the field of lung transplantation, the median survival after lung transplant remains below 5 years. Early rejection is a risk factor for the development of chronic rejection. In animal models of transplant tolerance, regulatory T cells (Tregs) can prevent the establishment of rejection., Methods: This study was designed to explore the dynamics of Tregs focally and systemically in lung transplant recipients. Sequential surveillance bronchoscopy results were available in 51 patients with at least four sequential samples recovered from each patient at defined times posttransplant. In 36 individuals, a complete year of follow-up data for BAL was analyzed. In 33 of these individuals had a complete year of follow-up data for peripheral blood monocyte cell specimens were also analyzed. Lung lavage cells were recovered from each bronchoscopy and corresponding blood draw and subjected to polychromatic flow cytometry. The percentage of CD4 lymphocytes, which expressed the intracellular transcription factor FoxP3 was recorded at each point. At each time point, lung biopsy specimens were scored for rejection., Results: Lung Treg frequency was significantly more variable than blood Treg frequency. Treg frequency in the lung was increased in the aftermath of acute rejection. In contrast, lung Treg frequency declined sequentially in patients demonstrating continued quiescence. Mean BAL Treg level integrated over the first transplant year correlated inversely with the degree of acute cellular rejection. In contrast, blood Treg levels demonstrated no correlation with lung pathology., Conclusions: Lung Tregs increase in the setting of acute cellular rejection, whereas declining levels of BAL Tregs correlates with immunologic quiescence.
- Published
- 2009
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35. Portopulmonary hypertension: imatinib as a novel treatment and the Emory experience with this condition.
- Author
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Tapper EB, Knowles D, Heffron T, Lawrence EC, and Csete M
- Subjects
- Antihypertensive Agents therapeutic use, Benzamides, Bosentan, Epoprostenol therapeutic use, Female, Humans, Hypertension, Portal drug therapy, Hypertension, Pulmonary drug therapy, Imatinib Mesylate, Liver Failure complications, Middle Aged, Piperazines therapeutic use, Protein Kinase Inhibitors therapeutic use, Pyrimidines therapeutic use, Sulfonamides therapeutic use, Treatment Outcome, Hypertension, Portal etiology, Hypertension, Pulmonary etiology, Liver Transplantation adverse effects
- Abstract
Portopulmonary hypertension (PoPH) is a common and feared complication of end-stage liver disease, and imposes increased risk of perioperative morbidity in the liver transplant patient. Herein, we present the first successful use of Imatinib in the perioperative management of a patient who was not responding to conventional treatments as well as our institution's experience with this devastating complication. Of patients evaluated for transplant, 4.1% were identified with PoPH, half of which were listed, and one quarter of which were transplanted. Patients with PoPH were twice as likely to be transplanted than all other candidates (48% vs 25%), though less likely to survive their first year (69% vs 86.4%).
- Published
- 2009
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36. Efficacy of oral ribavirin in lung transplant patients with respiratory syncytial virus lower respiratory tract infection.
- Author
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Pelaez A, Lyon GM, Force SD, Ramirez AM, Neujahr DC, Foster M, Naik PM, Gal AA, Mitchell PO, and Lawrence EC
- Subjects
- Administration, Oral, Adrenal Cortex Hormones administration & dosage, Adrenal Cortex Hormones therapeutic use, Adult, Aged, Antiviral Agents administration & dosage, Antiviral Agents therapeutic use, Bronchoalveolar Lavage Fluid, Female, Follow-Up Studies, Forced Expiratory Volume, Humans, Infusions, Intravenous, Lung Transplantation physiology, Male, Methylprednisolone Hemisuccinate administration & dosage, Methylprednisolone Hemisuccinate therapeutic use, Middle Aged, Postoperative Complications drug therapy, Pulmonary Disease, Chronic Obstructive surgery, Respiratory Syncytial Viruses, Ribavirin administration & dosage, Sarcoidosis surgery, Time Factors, Lung Transplantation adverse effects, Postoperative Complications virology, Respiratory Syncytial Virus Infections drug therapy, Ribavirin therapeutic use
- Abstract
Background: Respiratory syncytial virus (RSV) can cause severe lower respiratory tract infection (LRI) and is a risk factor for the development of bronchiolitis obliterans syndrome (BOS) after lung transplantation (LTx). Currently, the most widely used therapy for RSV is inhaled ribavirin. However, this therapy is costly and cumbersome. We investigated the utility of using oral ribavirin for the treatment of RSV infection after LTx., Methods: RSV was identified in nasopharyngeal swabs (NPS) or bronchoalveolar lavage (BAL) using direct fluorescent antibody (DFA) in 5 symptomatic LTx patients diagnosed with LRI. Data were collected from December 2005 and August 2007 and included: age; gender; type of LTx; underlying disease; date of RSV; pulmonary function prior to, during and up to 565 days post-RSV infection; need for mechanical ventilation; concurrent infections; and radiographic features. Patients received oral ribavirin for 10 days with solumedrol (10 to 15 mg/kg/day intravenously) for 3 days, until repeat NPS were negative., Results: Five patients had their RSV-LRI diagnosis made at a median of 300 days post-LTx. Mean forced expiratory volume in 1 second (FEV(1)) fell 21% (p < 0.012) during infection. After treatment, FEV(1) returned to baseline and was maintained at follow-up of 565 days. There were no complications and no deaths with oral therapy. A 10-day course of oral ribavirin cost $700 compared with $14,000 for nebulized ribavirin at 6 g/day., Conclusions: Treatment of RSV after LTx with oral ribavirin and corticosteroids is well tolerated, effective and less costly than inhaled ribavirin. Further studies are needed to directly compare the long-term efficacy of oral vs nebulized therapy for RSV.
- Published
- 2009
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37. Dapsone-induced hemolytic anemia in lung allograft recipients.
- Author
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Naik PM, Lyon GM 3rd, Ramirez A, Lawrence EC, Neujahr DC, Force S, and Pelaez A
- Subjects
- Anemia, Hemolytic epidemiology, Anti-Infective Agents adverse effects, Creatinine blood, Female, Hemoglobins metabolism, Humans, L-Lactate Dehydrogenase blood, Lung Diseases surgery, Male, Pulmonary Disease, Chronic Obstructive surgery, Regression Analysis, Retrospective Studies, Transplantation, Homologous, Anemia, Hemolytic chemically induced, Dapsone adverse effects, Lung Transplantation adverse effects, Postoperative Complications chemically induced
- Abstract
Background: Lung transplant (LT) recipients often receive dapsone for Pneumocystis jirovecii pneumonia (PCP) prophylaxis. However, the prevalence of dapsone-induced hematologic toxicity in LT recipients is unknown. We report a high prevalence of hemolytic anemia (HA) associated with dapsone use in LT patients when compared with other patients described in the literature who have been prescribed dapsone prophylaxis., Methods: We performed a retrospective chart review on all LT recipients who received dapsone prophylaxis between 2004 and 2006. Demographics, ideal body weight (IBW), severity of anemia, transfusion requirements, laboratory evidence of hemolysis, serum creatinine and glucose-6-phosphate deyhdrogenase (G6PD) enzyme levels were collected., Results: Forty-three patients received dapsone. Ten (22.7%) patients had HA, despite normal G6PD levels. The mean drop in hemoglobin from baseline was 2.7 g/dl (95% confidence interval [CI] 1.9 to 3.5, p < 0.0001). Of those patients with HA, 6 had elevated serum creatinine from baseline. The odds ratio for hemolysis was 4.75 for each 1.0-mg/dl increase in creatinine (95% CI 1.07 to 21.03, p = 0.04). Mean IBW for the HA group was 58.4 kg. A dapsone dose of 100 mg/day orally resulted in a mean dose of 1.7 mg/kg., Conclusions: The prevalence of dapsone-induced HA in LT recipients is 5-fold higher than the reported rate in the population of human immunodeficiency virus (HIV) patients. Individuals with renal failure or low body weight and for whom dose exceeds 1.5 mg/kg may be at increased risk for dapsone-induced HA. Although current CDC guidelines do not recommend adjusting dose by IBW or renal function, we suggest that consideration should be given to these dosing strategies.
- Published
- 2008
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38. Lung transplantation for COPD: one lung, two lungs, or none?
- Author
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Lawrence EC
- Subjects
- Humans, Middle Aged, Pulmonary Disease, Chronic Obstructive mortality, Registries, Smoking adverse effects, Smoking Prevention, Survival Rate, Lung Transplantation methods, Pulmonary Disease, Chronic Obstructive surgery
- Published
- 2008
- Full Text
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39. Bilateral lung transplant with pulmonary thromboendarterectomy for Eisenmenger's syndrome.
- Author
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Force SD, Kogon B, Pelaez A, Neujahr DC, Ramirez AM, Miller DL, and Lawrence EC
- Subjects
- Adult, Aneurysm complications, Eisenmenger Complex complications, Female, Humans, Thrombosis complications, Aneurysm surgery, Eisenmenger Complex surgery, Endarterectomy, Lung Transplantation methods, Pulmonary Artery surgery, Thrombosis surgery
- Abstract
Patients with secondary pulmonary hypertension frequently present for evaluation for lung transplantation. In some of these patients, Eisenmenger's syndrome has developed from chronic left to right intracardiac shunts. A smaller group of these patients will also have associated pulmonary artery aneurysms. There is a paucity of literature discussing this topic, however, and currents reports have suggested the need to replace the abnormal pulmonary artery. This paper discusses a patient in whom Eisenmenger's syndrome developed from an atrial septal defect, and resultant pulmonary artery aneurysms and mural thrombi, who underwent successful bilateral lung transplantation with thromboendarterectomy and atrial septal defect closure.
- Published
- 2008
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40. Candidate gene analysis in primary lymphedema.
- Author
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Ferrell RE, Kimak MA, Lawrence EC, and Finegold DN
- Subjects
- DNA Mutational Analysis, Exons, Gene Frequency, Genetic Testing, Humans, Introns, Lymphedema genetics, Mutation
- Abstract
Background: Primary lymphedema, the accumulation of protein-rich fluid in the interstitial space, is the clinical manifestation of mutations involved in lymphatic development and function. Mutations in three genes, VEGFR3, FOXC2, and SOX18, cause primary lymphedema. However, mutations in these three genes only account for a fraction of primary lymphedema. To identify other genes mutated in primary lymphedema, we resequenced twenty-five biologically plausible candidate genes for lymphedema in a large collection of primary lymphedema families., Methods and Results: Candidate genes were selected on the basis of gene expression in lymphatic endothelial cells, differential antigenic expression in lymphatics, and mouse studies of lymphatic development. The gene sequence was downloaded from GenBank and sequence primers designed to amplify 1 Kb of the 5' sequence, exons and flanking intron-exon boundaries, and 500 bp of the UTR of each gene. No common causative mutations were observed among the 25 genes screened. Single mutations were observed in elastin microfibril interfacer (EMILIN1), lymphocyte cytosolic protein 2 (LCP2), fatty acid binding protein 4 (FABP4), protein tyrosine kinase SYK (SYK), neuropilin-2 (NRP2), SpSRY-box 17 (SOX17), vascular cell adhesion molecule 1 (VCAM1), ROR orphan receptor C (RORC), and vascular endothelial growth factor B (VEGFB). Among these, the mutations in EMILIN1, RORC, LCP2, SYK, and VEGFB failed to segregate with lymphedema. The mutations in FABP4 (2), NRP2, SOX17, and VACM1 are consistent with being causative mutations, but occur in families too small to convincingly confirm cosegregation of mutation and phenotype., Conclusion: We excluded mutation in 21 biological candidate genes as a common cause of primary lymphedema. Mutations in FABP4, NRP2, SOX17 and VCAM1 are consistent with causality and follow up of these four genes are warranted. The evidence for FABP4 harboring lymphedema mutations is discussed.
- Published
- 2008
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41. HGF and MET mutations in primary and secondary lymphedema.
- Author
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Finegold DN, Schacht V, Kimak MA, Lawrence EC, Foeldi E, Karlsson JM, Baty CJ, and Ferrell RE
- Subjects
- Exons, Humans, Lymphangiectasis etiology, Lymphedema etiology, Proto-Oncogene Proteins c-met, Hepatocyte Growth Factor genetics, Lymphangiectasis genetics, Lymphedema genetics, Mutation, Proto-Oncogene Proteins genetics, Receptors, Growth Factor genetics
- Abstract
Background: Lymphedema is the abnormal accumulation of protein-rich fluid in the interstitial space. Primary lymphedema is a rare genetic condition with both autosomal dominant and autosomal recessive modes of inheritance. Three genes, FLT4 (VEGFR3), FOXC2, and SOX18 cause varying forms of primary lymphedema. In industrialized countries, secondary lymphedema is usually associated with cancer therapy and/or trauma. Recent observations suggested that hepatocyte growth factor/high affinity hepatocyte growth factor receptor (HGF/MET) were new candidate lymphedema genes., Methods and Results: The coding exons and flanking regions of HGF and MET were directly sequenced in 145 lymphedema probands, 59 unrelated women with secondary lymphedema following treatment for breast cancer, 21 individual patients with lymphedema and intestinal lymphangiectasia, and at least 159 unrelated ethnic matched control individuals. Mutations leading to truncation or missense changes in evolutionarily conserved residues of HGF and MET were identified. These mutations were not polymorphic in control individuals., Conclusions: The identification of HGF/MET mutations in primary lymphedema, lymphedema/lymphangiectasia, and breast cancer-associated secondary lymphedema suggests that the HGF/MET pathway is causal or alters susceptibility for a broad range of lymphedema phenotypes. The HGF/MET pathway provides a new target for the prevention and/or treatment of lymphedema.
- Published
- 2008
- Full Text
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42. Sequence variation in human succinate dehydrogenase genes: evidence for long-term balancing selection on SDHA.
- Author
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Baysal BE, Lawrence EC, and Ferrell RE
- Subjects
- Animals, Base Sequence, Gene Frequency, Haplotypes, Humans, Molecular Sequence Data, Pan troglodytes genetics, Protein Subunits genetics, Racial Groups genetics, Sequence Homology, Nucleic Acid, Time Factors, Electron Transport Complex II genetics, Polymorphism, Single Nucleotide, Selection, Genetic, Succinate Dehydrogenase genetics
- Abstract
Background: Balancing selection operating for long evolutionary periods at a locus is characterized by the maintenance of distinct alleles because of a heterozygote or rare-allele advantage. The loci under balancing selection are distinguished by their unusually high polymorphism levels. In this report, we provide statistical and comparative genetic evidence suggesting that the SDHA gene is under long-term balancing selection. SDHA encodes the major catalytical subunit (flavoprotein, Fp) of the succinate dehydrogenase enzyme complex (SDH; mitochondrial complex II). The inhibition of Fp by homozygous SDHA mutations or by 3-nitropropionic acid poisoning causes central nervous system pathologies. In contrast, heterozygous mutations in SDHB, SDHC, and SDHD, the other SDH subunit genes, cause hereditary paraganglioma (PGL) tumors, which show constitutive activation of pathways induced by oxygen deprivation (hypoxia)., Results: We sequenced the four SDH subunit genes (10.8 kb) in 24 African American and 24 European American samples. We also sequenced the SDHA gene (2.8 kb) in 18 chimpanzees. Increased nucleotide diversity distinguished the human SDHA gene from its chimpanzee ortholog and from the PGL genes. Sequence analysis uncovered two common SDHA missense variants and refuted the previous suggestions that these variants originate from different genetic loci. Two highly dissimilar SDHA haplotype clusters were present in intermediate frequencies in both racial groups. The SDHA variation pattern showed statistically significant deviations from neutrality by the Tajima, Fu and Li, Hudson-Kreitman-Aguadé, and Depaulis haplotype number tests. Empirically, the elevated values of the nucleotide diversity (% pi = 0.231) and the Tajima statistics (D = 1.954) in the SDHA gene were comparable with the most outstanding cases for balancing selection in the African American population., Conclusion: The SDHA gene has a strong signature of balancing selection. The SDHA variants that have increased in frequency during human evolution might, by influencing the regulation of cellular oxygen homeostasis, confer protection against certain environmental toxins or pathogens that are prevalent in Africa.
- Published
- 2007
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43. Sitaxsentan treatment for patients with pulmonary arterial hypertension discontinuing bosentan.
- Author
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Benza RL, Mehta S, Keogh A, Lawrence EC, Oudiz RJ, and Barst RJ
- Subjects
- Adolescent, Adult, Aged, Bosentan, Child, Double-Blind Method, Female, Follow-Up Studies, Humans, Male, Middle Aged, Treatment Outcome, Antihypertensive Agents therapeutic use, Endothelin Receptor Antagonists, Hypertension, Pulmonary drug therapy, Isoxazoles therapeutic use, Sulfonamides therapeutic use, Thiophenes therapeutic use
- Abstract
Background: Bosentan, an oral ET(A)/ET(B) receptor antagonist, is approved for the treatment of pulmonary arterial hypertension (PAH). However, some patients discontinue bosentan because of hepatotoxicity or inadequate efficacy. Sitaxsentan, an oral, ET(A)-selective endothelin antagonist currently under investigation, may be an alternative treatment option. In this study we evaluate the safety and efficacy of sitaxsentan in patients discontinuing bosentan., Methods: Forty-eight patients with idiopathic PAH or PAH associated with connective-tissue disease or congenital heart disease were randomized (double-blind) to a single daily dose of either 50 mg or 100 mg sitaxsentan. Thirty-five of the 48 patients discontinued bosentan because of inadequate efficacy, as judged by the investigator, and 13 discontinued bosentan for safety concerns. Study end-points included change in 6-minute walk distance (6MWD), change in World Health Organization (WHO) functional class, time to clinical worsening, and change in Borg dyspnea score (Borg) from baseline to Week 12., Results: With 100 mg sitaxsentan, 5 of 15 patients (33%) who discontinued bosentan because inadequate efficacy improved, demonstrating a >15% increase in 6MWD, vs 2 of 20 patients (10%) treated with 50 mg sitaxsentan. Fifteen percent and 20% of these patients had a >15% decrease in 6MWD in the 50- and 100-mg groups, respectively. Similar results were seen for the Borg and WHO functional class. Of the 12 patients discontinuing bosentan because of hepatotoxicity, 1 developed elevated liver enzymes at 13 weeks of sitaxsentan therapy. Overall, sitaxsentan was well tolerated., Conclusions: Sitaxsentan may represent a safe and efficacious alternative endothelin receptor antagonist for patients discontinuing bosentan.
- Published
- 2007
- Full Text
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44. Technique of right single-lung transplantation for idiopathic pulmonary fibrosis using cross-field ventilation.
- Author
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Force SD, Pelaez A, Neujahr DC, Ramirez AM, Whitley W, Miller DL, and Lawrence EC
- Subjects
- Humans, Intubation, Intratracheal, Male, Middle Aged, Lung Transplantation methods, Pulmonary Fibrosis surgery, Respiration, Artificial methods
- Published
- 2007
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45. Human adaptive evolution at Myostatin (GDF8), a regulator of muscle growth.
- Author
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Saunders MA, Good JM, Lawrence EC, Ferrell RE, Li WH, and Nachman MW
- Subjects
- Animals, Black People genetics, Gene Frequency, Genetic Variation, Haplotypes genetics, Humans, Mammals genetics, Myostatin, Polymorphism, Single Nucleotide, Selection, Genetic, White People genetics, Adaptation, Physiological, Evolution, Molecular, Muscle Development physiology, Transforming Growth Factor beta physiology
- Abstract
Myostatin (GDF8) is a negative regulator of muscle growth in mammals, and loss-of-function mutations are associated with increased skeletal-muscle mass in mice, cattle, and humans. Here, we show that positive natural selection has acted on human nucleotide variation at GDF8, since the observed ratio of nonsynonymous:synonymous changes among humans is significantly greater than expected under the neutral model and is strikingly different from patterns observed across mammalian orders. Furthermore, extended haplotypes around GDF8 suggest that two amino acid variants have been subject to recent positive selection. Both mutations are rare among non-Africans yet are at frequencies of up to 31% in sub-Saharan Africans. These signatures of selection at the molecular level suggest that human variation at GDF8 is associated with functional differences.
- Published
- 2006
- Full Text
- View/download PDF
46. Outcomes of delayed chest closure after bilateral lung transplantation.
- Author
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Force SD, Miller DL, Pelaez A, Ramirez AM, Vega D, Barden B, and Lawrence EC
- Subjects
- Blood Loss, Surgical, Bone Wires, Cardiomyopathies, Cardiopulmonary Bypass, Edema, Female, Humans, Hypertension, Pulmonary, Intraoperative Complications, Male, Middle Aged, Occlusive Dressings, Postoperative Period, Pulmonary Edema, Reperfusion Injury, Retrospective Studies, Sternum surgery, Suture Techniques, Time Factors, Treatment Outcome, Lung Transplantation methods, Thoracotomy methods
- Abstract
Background: Delayed chest closure (DCC) may be used after bilateral lung transplantation when significant bleeding/coagulopathy or severe pulmonary edema exists. Primary chest closure (PCC) in these patients can lead to heart and lung compression causing cardiopulmonary instability. The purpose of this study is to describe factors associated with DCC and evaluate outcomes after DCC., Methods: We performed a retrospective review of all patients undergoing bilateral lung transplantation between September 2003 and March 2005. Statistical significance was determined by two-tailed t test or Fisher's exact test., Results: Twenty-eight bilateral lung transplantations were performed. Indication for transplant was chronic obstructive pulmonary disease (13), pulmonary fibrosis (5), cystic fibrosis (5), sarcoidosis (3), and pulmonary hypertension (1). Seven patients (25%) required DCC. Mean time to DCC was 5.3 days. Six patients (86%) with DCC required tracheostomy versus 4 patients (20%) with PCC (p = 0.003). Mean days to discharge was 44 in the DCC group and 21 in the PCC group (p = 0.03). Thirty-day survival was 100% in the DCC group and 95% in the PCC group (p = 1.0). There were no wound infections in either group, and 1 patient in the PCC group had sternal nonunion. Delayed chest closure was associated with cardiopulmonary bypass use (p = 0.006), cardiopulmonary bypass time longer than mean cardiopulmonary bypass time (mean, 224 minutes; p = 0.04), PaO2/FiO2 less than mean + 1 SD (value = 4.63, p = 0.0002), evidence of moderate/severe reperfusion injury on chest radiograph (p = 0.0002), and PaO2/FiO2 less than mean plus moderate/severe reperfusion injury on chest radiograph (p = 0.002)., Conclusions: Cardiopulmonary bypass use, prolonged cardiopulmonary bypass time, and significant reperfusion injury, as determined by chest radiograph and a low PaO2/FiO2 ratio were all associated with an increased incidence of DCC in our bilateral lung transplantation patients. These patients had no wound infections or sternal complications, and although they had longer hospital stays than PCC patients, DCC did not affect operative survival. Delayed chest closure can be employed safely, when necessary, after bilateral lung transplantation with outcomes similar to patients with PCC.
- Published
- 2006
- Full Text
- View/download PDF
47. Treatment of pulmonary arterial hypertension with the selective endothelin-A receptor antagonist sitaxsentan.
- Author
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Barst RJ, Langleben D, Badesch D, Frost A, Lawrence EC, Shapiro S, Naeije R, and Galie N
- Subjects
- Adolescent, Adult, Aged, Bosentan, Disease Progression, Dose-Response Relationship, Drug, Double-Blind Method, Dyspnea drug therapy, Dyspnea etiology, Exercise Test, Exercise Tolerance, Female, Health Status Indicators, Hemodynamics, Humans, Hypertension, Pulmonary complications, Hypertension, Pulmonary physiopathology, Male, Middle Aged, Risk Assessment, Sulfonamides therapeutic use, Treatment Outcome, Antihypertensive Agents therapeutic use, Endothelin A Receptor Antagonists, Hypertension, Pulmonary drug therapy, Isoxazoles therapeutic use, Thiophenes therapeutic use
- Abstract
Objectives: We sought to determine the optimal dose of the selective endothelin A (ET(A)) receptor antagonist sitaxsentan for the treatment of pulmonary arterial hypertension (PAH); for observation only, an open-label (OL) bosentan arm was included., Background: Endothelin is a mediator of PAH. In a preliminary PAH study, the selective ET(A) receptor antagonist sitaxsentan improved six-min walk (6MW) distance, World Health Organization (WHO) functional class (FC), and hemodynamics., Methods: In this double-blind, placebo-controlled 18-week study, 247 PAH patients (idiopathic, or associated with connective tissue disease or congenital heart disease) were randomized; 245 patients were treated: placebo (n = 62), sitaxsentan 50 mg (n = 62) or 100 mg (n = 61), or OL (6MW tests, Borg dyspnea scores, and WHO FC assessments third-party blind) bosentan (n = 60). The primary end point was change in 6MW distance from baseline to week 18. Secondary end points included change in WHO FC, time to clinical worsening, and change in Borg dyspnea score., Results: At week 18, patients treated with sitaxsentan 100 mg had an increased 6MW distance compared with the placebo group (31.4 m, p = 0.03), and an improved WHO FC (p = 0.04). The placebo-subtracted treatment effect for sitaxsentan 50 mg was 24.2 m (p = 0.07) and for OL bosentan, 29.5 m (p = 0.05). The incidence of elevated hepatic transaminases (>3x the upper limit of normal) was 6% for placebo, 5% for sitaxsentan 50 mg, 3% for sitaxsentan 100 mg, and 11% for bosentan., Conclusions: Treatment with the selective ET(A) receptor antagonist sitaxsentan, orally once daily at a dose of 100 mg, improves exercise capacity and WHO FC in PAH patients, with a low incidence of hepatic toxicity.
- Published
- 2006
- Full Text
- View/download PDF
48. Effects of aerosol vs IV UT-15 on prostaglandin H2 analog-induced pulmonary hypertension in sheep.
- Author
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Sandifer BL, Brigham KL, Lawrence EC, and Parker RE
- Subjects
- Aerosols, Animals, Epoprostenol administration & dosage, Hypertension, Pulmonary chemically induced, Injections, Intravenous, Sheep, Epoprostenol analogs & derivatives, Hypertension, Pulmonary drug therapy, Prostaglandin H2 analogs & derivatives
- Published
- 2005
- Full Text
- View/download PDF
49. Potent effects of aerosol compared with intravenous treprostinil on the pulmonary circulation.
- Author
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Sandifer BL, Brigham KL, Lawrence EC, Mottola D, Cuppels C, and Parker RE
- Subjects
- Acute Disease, Administration, Inhalation, Aerosols administration & dosage, Animals, Antihypertensive Agents administration & dosage, Disease Models, Animal, Epoprostenol administration & dosage, Female, Injections, Intravenous, Male, Sheep, Treatment Outcome, Blood Pressure drug effects, Epoprostenol analogs & derivatives, Hypertension, Pulmonary drug therapy, Hypertension, Pulmonary physiopathology, Pulmonary Circulation drug effects, Recovery of Function drug effects, Vasodilation drug effects
- Abstract
Inhaled vasodilator therapy for pulmonary hypertension may decrease the systemic side effects commonly observed with systemic administration. Inhaled medications only reach ventilated areas of the lung, so local vasodilation may improve ventilation-perfusion matching and oxygenation. We compared the effects of intravenous vs. aerosolized treprostinil on pulmonary and systemic hemodynamics in an unanesthetized sheep model of sustained acute pulmonary hypertension. Acute, stable pulmonary hypertension was induced in instrumented unanesthetized sheep by infusing a PGH(2) analog, U-44069. The sheep were then administered identical doses of treprostinil either intravenously or by aerosol. Systemic and pulmonary hemodynamics were recorded during each administration. Both intravenous and aerosol delivery of treprostinil reduced pulmonary vascular resistance and pulmonary arterial pressure, but the effect was significantly greater with aerosol delivery (P < 0.05). Aerosol delivery of treprostinil had minimal effects on systemic hemodynamics, whereas intravenous delivery increased heart rate and cardiac output and decreased left atrial pressure and systemic blood pressure. Aerosol delivery of the prostacyclin analog treprostinil has a greater vasodilatory effect in the lung with minimal alterations in systemic hemodynamics compared with intravenous delivery of the drug. We speculate that this may result from treprostinil stimulated production of vasodilatory mediators from pulmonary epithelium.
- Published
- 2005
- Full Text
- View/download PDF
50. Heart rate variability is associated with polymorphic variation in the choline transporter gene.
- Author
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Neumann SA, Lawrence EC, Jennings JR, Ferrell RE, and Manuck SB
- Subjects
- Acetylcholine physiology, Adult, Female, Heart Rate genetics, Humans, Male, Middle Aged, Models, Genetic, Parasympathetic Nervous System physiology, Synaptic Transmission physiology, White People legislation & jurisprudence, Electrocardiography statistics & numerical data, Genetic Variation, Heart Rate physiology, Membrane Transport Proteins genetics, Polymorphism, Single Nucleotide genetics
- Abstract
Objective: The objective of this study was to determine whether interindividual variation in parasympathetic (cholinergic) and sympathetic (adrenergic) regulation of heart rate (as estimated by frequency components of heart rate variability [HRV]) may be accounted for, in part, by genetic variation in the choline transporter, a component of acetylcholine neurotransmission., Methods: Resting HRV estimates of high- (HF) and low-frequency (LF) power and LF/HF ratio were determined from electrocardiogram recordings collected continuously over 5 minutes in 413 white individuals of European ancestry (49% men; aged 30-54 years [mean, 44 years]). Subjects were genotyped for a single nucleotide polymorphism (SNP) located in the 3' untranslated region of the choline transporter gene (CHT1). Frequencies of the alternate CHT1 alleles, labeled G and T, were 76% and 24%., Results: Compared with GG homozygotes, participants having any T allele had greater HF power (p <.02), lower LF power (p <.02), and lower LF/HF ratios (p <.005). Relative to men, women had lower LF power (p <.001) and lower LF/HF ratios (p <.005)., Conclusions: These findings show that polymorphic variation in the CHT1 gene is associated significantly with interindividual variability in HRV indices related to parasympathetic (cholinergic) activity.
- Published
- 2005
- Full Text
- View/download PDF
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