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Featured researches published by Megan Beems.


Human Resources for Health | 2009

Agreement between physicians and non-physician clinicians in starting antiretroviral therapy in rural Uganda

Ashwin Vasan; Nathan Kenya-Mugisha; Kwonjune J. Seung; Marion Achieng; Patrick Banura; Frank Lule; Megan Beems; Jim Todd; Elizabeth Madraa

BackgroundThe scarcity of physicians in sub-Saharan Africa – particularly in rural clinics staffed only by non-physician health workers – is constraining access to HIV treatment, as only they are legally allowed to start antiretroviral therapy in the HIV-positive patient. Here we present a pilot study from Uganda assessing agreement between non-physician clinicians (nurses and clinical officers) and physicians in their decisions as to whether to start therapy.MethodsWe conducted the study at 12 government antiretroviral therapy sites in three regions of Uganda, all of which had staff trained in delivery of antiretroviral therapy using the WHO Integrated Management of Adult and Adolescent Illness guidelines for chronic HIV care. We collected seven key variables to measure patient assessment and the decision as to whether to start antiretroviral therapy, the primary variable of interest being the Final Antiretroviral Therapy Recommendation. Patients saw either a clinical officer or nurse first, and then were screened identically by a blinded physician during the same clinic visit. We measured inter-rater agreement between the decisions of the non-physician health workers and physicians in the antiretroviral therapy assessment variables using simple and weighted Kappa analysis.ResultsTwo hundred fifty-four patients were seen by a nurse and physician, while 267 were seen by a clinical officer and physician. The majority (> 50%) in each arm of the study were in World Health Organization Clinical Stages I and II and therefore not currently eligible for antiretroviral therapy according to national antiretroviral therapy guidelines. Nurses and clinical officers both showed moderate to almost perfect agreement with physicians in their Final Antiretroviral Therapy Recommendation (unweighted κ = 0.59 and κ = 0.91, respectively). Agreement was also substantial for nurses versus physicians for assigning World Health Organization Clinical Stage (weighted κ = 0.65), but moderate for clinical officers versus physicians (κ = 0.44).ConclusionBoth nurses and clinical officers demonstrated strong agreement with physicians in deciding whether to initiate antiretroviral therapy in the HIV patient. This could lead to immediate benefits with respect to antiretroviral therapy scale-up and decentralization to rural areas in Uganda, as non-physician clinicians – particularly clinical officers – demonstrated the capacity to make correct clinical decisions to start antiretroviral therapy. These preliminary data warrant more detailed and multicountry investigation into decision-making of non-physician clinicians in the management of HIV disease with antiretroviral therapy, and should lead policy-makers to more carefully explore task-shifting as a shorter-term response to addressing the human resource crisis in HIV care and treatment.


Progress in Lipid Research | 2010

Biosynthesis and bioavailability of long-chain polyunsaturated fatty acids in non-alcoholic fatty liver disease

Juan Guillermo Gormaz; Ramón Rodrigo; Luis A. Videla; Megan Beems

Non-alcoholic fatty liver disease (NAFLD) has a high occurrence in most countries. Recent studies estimate its prevalence to be near 30% in United States, Italian and Japanese general adult populations. NAFLD commonly presents along with obesity and insulin resistance (IR), pathologies that share with NAFLD metabolic and inflammatory components. These conditions, particularly NAFLD, are associated with alterations in the bioavailability of long-chain polyunsaturated fatty acids (LCPUFAs). In the human population, the bioavailability of LCPUFAs depends both on endogenous biosynthesis and diet amount of preformed LCPUFAs. However, the lower liver LCPUFAs product/precursor ratio namely (20:5n-3+22:6n-3)/18:3n-3, 20:4n-6/18:2n-6 present in common Western diets, makes critical an adequate pathway activity to ensure minimum bioavailability of LCPUFAs in most Western populations. The key step of this biosynthesis involves Δ5 and Δ6-desaturases, whose activities are altered in NAFLD. During the disease, the presence of molecular activators of these two enzymes does not correlate with the scarce LCPUFAS biosynthesis observed. The key to this apparent contradiction, or at least part of it, could be explained on the basis of the possible sensitivity of the desaturases to oxidative stress; a metabolic condition strongly linked to inflammatory pathologies such as NAFLD, obesity and IR and that, according to latest research, not only would be consequence but also possibly a cause of these diseases. The present review is focused on the relationship between NAFLD and the bioavailability of LCPUFAs, with special reference to the role that oxidative stress could play in the modulation of the liver fatty acid desaturase activity.


BMC Pregnancy and Childbirth | 2009

Optimism/pessimism and health-related quality of life during pregnancy across three continents: a matched cohort study in China, Ghana, and the United States

Cheryl A. Moyer; Huixia Yang; Yao Kwawukume; Anu Gupta; YuChun Zhu; Isaac O. Koranteng; Yasmin Elsayed; Yumei Wei; Jonathan B. Greene; Cecilia L. Calhoun; Geraldine Ekpo; Megan Beems; Megan Ryan; Richard Adanu; Frank W.J. Anderson

BackgroundLittle is known about how optimism/pessimism and health-related quality of life compare across cultures.MethodsThree samples of pregnant women in their final trimester were recruited from China, Ghana, and the United States (U.S.). Participants completed a survey that included the Life Orientation Test - Revised (LOT-R, an optimism/pessimism measure), the Short Form 12 (SF-12, a quality of life measure), and questions addressing health and demographic factors. A three-country set was created for analysis by matching women on age, gestational age at enrollment, and number of previous pregnancies. Anovas with post-hoc pairwise comparisons were used to compare results across the cohorts. Multivariate regression analysis was used to create a model to identify those variables most strongly associated with optimism/pessimism.ResultsLOT-R scores varied significantly across cultures in these samples, with Ghanaian pregnant women being the most optimistic and least pessimistic and Chinese pregnant women being the least optimistic overall and the least pessimistic in subscale analysis. Four key variables predicted approximately 20% of the variance in overall optimism scores: country of origin (p = .006), working for money (p = .05); level of education (p = .002), and ever being treated for emotional issues with medication (p < .001). Quality of life scores also varied by country in these samples, with the most pronounced difference occurring in the vitality measure. U.S. pregnant women reported far lower vitality scores than both Chinese and Ghanaian pregnant women in our sample.ConclusionThis research raises important questions regarding what it is about country of origin that so strongly influences optimism/pessimism among pregnant women. Further research is warranted exploring underlying conceptualization of optimism/pessimism and health related quality of life across countries.


Journal of Biological Chemistry | 2012

Sequence variation in promoter of Ica1 gene, which encodes protein implicated in type 1 diabetes, causes transcription factor autoimmune regulator (AIRE) to increase its binding and down-regulate expression

Samantha M. Bonner; Susan Pietropaolo; Yong Fan; Yigang Chang; Praveen Sethupathy; Michael P. Morran; Megan Beems; Nick Giannoukakis; Giuliana Trucco; Michael Palumbo; Michele Solimena; Alberto Pugliese; Constantin Polychronakos; Massimo Trucco; Massimo Pietropaolo

Background: Immunologic tolerance to tissue-restricted self-antigens primarily takes place in the thymus. Results: Sequence variation within the Ica1 promoter is associated with increased autoimmune regulator (AIRE) binding and transcription repression of ICA69 in medullary thymic epithelial cells. Conclusion: AIRE is a transcription repressor within the NOD mouse Ica1 promoter. Significance: A newly identified role for AIRE as a transcription repressor in medullary thymic epithelial cells. ICA69 (islet cell autoantigen 69 kDa) is a protein implicated in type 1 diabetes mellitus in both the non-obese diabetic (NOD) mouse model and humans. ICA69 is encoded by the Ica1 gene on mouse chromosome 6 A1-A2. We previously reported reduced ICA69 expression in the thymus of NOD mice compared with thymus of several non-diabetic mouse strains. We propose that reduced thymic ICA69 expression could result from variations in transcriptional regulation of the gene and that polymorphisms within the Ica1 core promoter may partially determine this transcriptional variability. We characterized the functional promoter of Ica1 in NOD mice and compared it with the corresponding portions of Ica1 in non-diabetic C57BL/6 mice. Luciferase reporter constructs demonstrated that the NOD Ica1 promoter region exhibited markedly reduced luciferase expression in transiently transfected medullary thymus epithelial (mTEC+) and B-cell (M12)-derived cell lines. However, in a non-diabetic strain, C57BL/6, the Ica1 promoter region was transcriptionally active when transiently transfected into the same cell lines. We concomitantly identified five single nucleotide polymorphisms within the NOD Ica1 promoter. One of these single nucleotide polymorphisms increases the binding affinity for the transcription factor AIRE (autoimmune regulator), which is highly expressed in thymic epithelial cells, where it is known to play a key role regulating self-antigen expression. We conclude that polymorphisms within the NOD Ica1 core promoter may determine AIRE-mediated down-regulation of ICA69 expression in medullary thymic epithelial cells, thus providing a novel mechanistic explanation for the loss of immunologic tolerance to this self-antigen in autoimmunity.


Journal of Surgical Oncology | 2018

Nomogram predicting the risk of recurrence after curative-intent resection of primary non-metastatic gastrointestinal neuroendocrine tumors: An analysis of the U.S. Neuroendocrine Tumor Study Group

Katiuscha Merath; Fabio Bagante; Eliza W. Beal; Alexandra G. Lopez-Aguiar; George A. Poultsides; Eleftherios Makris; Flavio G. Rocha; Zaheer S. Kanji; Sharon M. Weber; Alexander V. Fisher; Ryan C. Fields; Bradley Krasnick; Kamran Idrees; Paula Marincola Smith; Cliff Cho; Megan Beems; Carl Schmidt; Mary Dillhoff; Shishir K. Maithel; Timothy M. Pawlik

The risk of recurrence after resection of non‐metastatic gastro‐entero‐pancreatic neuroendocrine tumors (GEP‐NET) is poorly defined. We developed/validated a nomogram to predict risk of recurrence after curative‐intent resection.


Surgery | 2018

Influence of carcinoid syndrome on the clinical characteristics and outcomes of patients with gastroenteropancreatic neuroendocrine tumors undergoing operative resection

Charles W. Kimbrough; Eliza W. Beal; Mary Dillhoff; Carl Schmidt; Timothy M. Pawlik; Alexandra G. Lopez-Aguiar; George A. Poultsides; Eleftherios Makris; Flavio G. Rocha; Angelena Crown; Daniel E. Abbott; Alexander V. Fisher; Ryan C. Fields; Bradley Krasnick; Kamran Idrees; Paula Marincola-Smith; Clifford S. Cho; Megan Beems; Shishir K. Maithel; Jordan M. Cloyd

Background: The incidence, clinical characteristics, and long‐term outcomes of patients with gastroenteropancreatic neuroendrocrine tumors and carcinoid syndrome undergoing operative resection have not been well characterized. Methods: Patients undergoing resection of primary or metastatic gastroenteropancreatic neuroendrocrine tumors between 2000 and 2016 were identified from an 8‐institution collaborative database. Clinicopathologic and postoperative characteristics as well as overall survival and disease‐free survival were compared among patients with and without carcinoid syndrome. Results: Among 2,182 patients who underwent resection, 139 (6.4%) had preoperative carcinoid syndrome. Patients with carcinoid syndrome were more likely to have midgut primary tumors (44.6% vs 21.4%, P < .001), lymph node metastasis (63.4% vs 44.3%, P < .001), and metastatic disease (62.8% vs 26.7%, P < .001). There was no difference in tumor differentiation, grade, or Ki67 status. Perioperative carcinoid crisis was rare (1.6% vs 0%, P < .01), and the presence of preoperative carcinoid syndrome was not associated with postoperative morbidity (38.8% vs 45.5%, P = .129). Substantial symptom improvement was reported in 59.5% of patients who underwent curative‐intent resection, but occurred in only 22.7% who underwent debulking. Despite an association on univariate analysis (P = .04), carcinoid syndrome was not independently associated with disease‐free survival after controlling for confounding factors (hazard ratio 0.97, 95% confidence interval 0.64–1.45). Preoperative carcinoid syndrome was not associated with overall survival on univariate or multivariate analysis. Conclusion: Among patients undergoing operative resection of gastroenteropancreatic neuroendrocrine tumors, the prevalence of preoperative carcinoid syndrome was low. Although operative intervention with resection or especially debulking in patients with carcinoid syndrome was disappointing and often failed to improve symptoms, after controlling for markers of tumor burden, carcinoid syndrome was not independently associated with worse disease‐free survival or overall survival.


Surgery | 2018

Margin status and long-term prognosis of primary pancreatic neuroendocrine tumor after curative resection: Results from the US Neuroendocrine Tumor Study Group

Xu-Feng Zhang; Zheng Wu; Jordan M. Cloyd; Alexandra G. Lopez-Aguiar; George A. Poultsides; Eleftherios Makris; Flavio Rocha; Zaheer S. Kanji; Sharon M. Weber; Alexander V. Fisher; Ryan C. Fields; Bradley Krasnick; Kamran Idrees; Paula Marincola Smith; C.S. Cho; Megan Beems; Carl Schmidt; Mary Dillhoff; Shishir K. Maithel; Timothy M. Pawlik

Background: The impact of margin status on resection of primary pancreatic neuroendocrine tumors has been poorly defined. The objectives of the present study were to determine the impact of margin status on long‐term survival of patients with pancreatic neuroendocrine tumors after curative resection and evaluate the impact of reresection to obtain a microscopically negative margin. Methods: Patients who underwent curative‐intent resection for pancreatic neuroendocrine tumors between 2000 and 2016 were identified at 8 hepatobiliary centers. Overall and recurrence‐free survival were analyzed relative to surgical margin status using univariable and multivariable analyses. Results: Among 1,020 patients, 866 (84.9%) had an R0 (>1 mm margin) resection, whereas 154 (15.1%) had an R1 (≤1 mm margin) resection. R1 resection was associated with a worse recurrence‐free survival (10‐year recurrence‐free survival, R1 47.3% vs R0 62.8%, hazard ratio 1.8, 95% confidence interval 1.2–2.7, P = .002); residual tumor at either the transection margin (R1t) or the mobilization margin (R1m) was associated with increased recurrence versus R0 (R1t versus R0: hazard ratio 1.8, 95% confidence interval 1.0–3.0, P = .033; R1m versus R0: hazard ratio 1.3, 95% confidence interval 1.0–1.7, P = .060). In contrast, margin status was not associated with overall survival (10‐year overall survival, R1 71.1% vs R0 71.8%, P = .392). Intraoperatively, 539 (53.6%) patients had frozen section evaluation of the surgical margin; 49 (9.1%) patients had a positive margin on frozen section analysis; 38 of the 49 patients (77.6%) had reresection, and a final R0 (secondary R0) margin was achieved in 30 patients (78.9%). Extending resection to achieve an R0 status remained associated with worse overall survival (hazard ratio 3.1, 95% confidence interval 1.6–6.2, P = .001) and recurrence‐free survival (hazard ratio 2.6, 95% confidence interval 1.4–5.0, P = .004) compared with primary R0 resection. On multivariable analyses, tumor‐specific factors, such as cellular differentiation, perineural invasion, Ki‐67 index, and major vascular invasion, rather than surgical margin, were associated with long‐term outcomes. Conclusion: Margin status was not associated with long‐term survival. The reresection of an initially positive surgical margin to achieve a negative margin did not improve the outcome of patients with pancreatic neuroendocrine tumors. Parenchymal‐sparing pancreatic procedures for pancreatic neuroendocrine tumors may be appropriate when feasible.


Journal of Gastrointestinal Surgery | 2018

Surgery Provides Long-Term Survival in Patients with Metastatic Neuroendocrine Tumors Undergoing Resection for Non-Hormonal Symptoms

Jeffery Chakedis; Eliza W. Beal; Alexandra G. Lopez-Aguiar; George A. Poultsides; Eleftherios Makris; Flavio G. Rocha; Zaheer S. Kanji; Sharon M. Weber; Alexander V. Fisher; Ryan C. Fields; Bradley Krasnick; Kamran Idrees; Paula Marincola-Smith; Clifford S. Cho; Megan Beems; Timothy M. Pawlik; Shishir K. Maithel; Carl Schmidt; Mary Dillhoff


Journal of Clinical Oncology | 2018

Defining the number of lymph nodes needed to accurately stage small bowel neuroendocrine tumors: An 8-institution study from the US neuroendocrine tumor study group.

Mohammad Zaidi; Alexandra G. Lopez-Aguiar; Mary Dillhoff; Eliza W. Beal; George A. Poultsides; Eleftherios Makris; Flavio G. Rocha; Angelena Crown; Kamran Idrees; Paula Marincola Smith; Hari Nathan; Megan Beems; Daniel E. Abbott; James R. Barrett; Ryan C. Fields; Jesse T. Davidson; Kenneth Cardona; Shishir K. Maithel


Journal of Clinical Oncology | 2018

Defining the role of lymphadenectomy for pancreatic neuroendocrine tumors: An eight institution study of 695 patients from the U.S. Neuroendocrine Tumor Study Group.

Alexandra G. Lopez-Aguiar; Mohammad Zaidi; Mary Dillhoff; Eliza W. Beal; George A. Poultsides; Eleftherios Makris; Flavio G. Rocha; Zaheer S. Kanji; Kamran Idrees; Paula Marincola Smith; Clifford S. Cho; Megan Beems; Sharon M. Weber; Alexandra V. Fisher; Ryan C. Fields; Bradley Krasnick; Kenneth Cardona; Shishir K. Maithel

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Mary Dillhoff

The Ohio State University Wexner Medical Center

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Ryan C. Fields

Washington University in St. Louis

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Flavio G. Rocha

Brigham and Women's Hospital

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Kamran Idrees

Vanderbilt University Medical Center

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Eliza W. Beal

The Ohio State University Wexner Medical Center

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Bradley Krasnick

Washington University in St. Louis

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