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Kaplow K, Ruck JM, Levan ML, Thomas AG, Stewart D, Massie AB, Sung HC, Pisano SF, Sidoti C, Segev DL, Sinacore J, Waterman AD. National Attitudes Toward Living Kidney Donation in the United States: Results of a Public Opinion Survey. Kidney Med 2024; 6:100788. [PMID: 38435064 PMCID: PMC10906424 DOI: 10.1016/j.xkme.2023.100788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/05/2024] Open
Abstract
Rationale & Objective Understanding national attitudes about living kidney donation will enable us to identify and address existing disincentives to living kidney donation. We performed a national survey to describe living kidney donation perceptions, perceived factors that affect the willingness to donate, and analyzed differences by demographic subgroups. Study Design The survey items captured living kidney donation awareness, living kidney donation knowledge, willingness to donate, and barriers and facilitators to living kidney donation. Setting & Population We surveyed 802 US adults (aged 25-65 years) in June 2021, randomly selected from an online platform with diverse representation. Analytical Approach We developed summed, scaled indices to assess the association between the living kidney donation knowledge (9 items) and the willingness to donate (8 items) to self-reported demographic characteristics and other variables of interest using analysis of variance. All other associations for categorical questions were calculated using Pearson's χ2 and Fisher exact tests. We inductively evaluated free-text responses to identify additional barriers and facilitators to living kidney donation. Results Most (86.6%) of the respondents reported that they might or would definitely consider donating a kidney while they were still living. Barriers to living kidney donation included concerns about the risk of the surgery, paying for medical expenses, and potential health effects. Facilitators to living kidney donation included having information on the donation surgery's safety, knowing that the donor would not have to pay for medical expenses related to the donation, and hearing living kidney donation success stories. Awareness of the ability to participate in kidney-paired donation was associated with a higher willingness to donate. Limitations Potential for selection bias resulting from the use of survey panels and varied incentive amounts, and measurement error related to respondents' attention level. Conclusions Most people would consider becoming a living kidney donor. Increased rates of living kidney donation may be possible with investment in culturally competent educational interventions that address risks associated with donating, policies that reduce financial disincentives, and communication campaigns that raise awareness of kidney-paired donation and living kidney donation.
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Affiliation(s)
- Katya Kaplow
- Department of Surgery, New York University Langone, New York, New York
| | - Jessica M. Ruck
- Department of Surgery, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Macey L. Levan
- Department of Surgery, New York University Langone, New York, New York
| | - Alvin G. Thomas
- Department of Surgery, New York University Langone, New York, New York
- Department of Surgery, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Darren Stewart
- Department of Surgery, New York University Langone, New York, New York
| | - Allan B. Massie
- Department of Surgery, New York University Langone, New York, New York
| | - Hannah C. Sung
- Department of Surgery, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Sarah F. Pisano
- Department of Surgery, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Carolyn Sidoti
- Department of Surgery, New York University Langone, New York, New York
| | - Dorry L. Segev
- Department of Surgery, New York University Langone, New York, New York
| | | | - Amy D. Waterman
- Department of Surgery, Houston Methodist Hospital, Houston, Texas
- Department of Surgery, J.C. Walter Jr Transplant Center, Houston Methodist Hospital, Houston, Texas
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Vanterpool KB, Diallo K, Kim E, Van Pilsum Rasmussen SE, Johnson MA, Predmore Z, Brundage J, Barnaba B, Desai N, Levan ML, Sung HC, Kates O, Sugarman J, Durand CM. Patient Perspectives on Solid Organ Transplantation From Donors With Hepatitis C Viremia to Recipients Without Hepatitis C Viremia. Open Forum Infect Dis 2024; 11:ofae015. [PMID: 38434612 PMCID: PMC10906703 DOI: 10.1093/ofid/ofae015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Accepted: 01/08/2024] [Indexed: 03/05/2024] Open
Abstract
Background Organ transplantation from donors with hepatitis C viremia (HCV) to recipients without HCV (HCV D+/R-) has excellent medical outcomes. Less is known about the psychosocial impact and experiences of HCV D+/R- recipients, particularly outside of clinical trials. Methods We conducted in-depth, semistructured interviews with 24 HCV D+/R- recipients (kidney, n = 8; lung, n = 7; liver, n = 5; heart, n = 3; simultaneous heart and kidney, n = 1) who received transplants outside of clinical trials and were treated for HCV after transplant to assess their experiences and perspectives. We used thematic analysis to analyze the interviews. Results Interviewees' reasons for accepting an HCV D + organ were based on perceived benefits and confidence in the effectiveness of HCV treatment. The majority (62%) received HCV treatment within 1 month after transplant (range, 1 day-2 months). Most interviewees reported positive transplant outcomes, including reduced wait times and improved survival, health, physical activity, and quality of life. Overall, themes and experiences did not differ significantly between different organ transplant types. Generally, interviewees did not perceive stigma from those aware of the HCV D+ transplant; yet, disclosure was selective and a few recipients reported concerns from family members about posttransplant HCV transmission risk. Other common concerns included treatment costs and delays, which were not always anticipated by recipients. Conclusions Our findings suggest that HCV D+/R- kidney, liver, and heart and lung transplant recipients outside of clinical trials had overall positive experiences. However, HCV transmission risk, treatments costs, and treatment delays were a source of concern that might be mitigated with targeted pretransplant education.
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Affiliation(s)
- Karen B Vanterpool
- Department of Surgery, NYU Grossman School of Medicine, New York, New York, USA
| | - Kadiatou Diallo
- Department of Surgery, NYU Grossman School of Medicine, New York, New York, USA
| | - Ellie Kim
- Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | | | - Morgan A Johnson
- Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Zachary Predmore
- Department of Health Policy and Management, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Janetta Brundage
- Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Brittany Barnaba
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Niraj Desai
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Macey L Levan
- Department of Surgery, NYU Grossman School of Medicine, New York, New York, USA
- Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Department of Population Health, NYU Grossman School of Medicine, New York, New York, USA
| | - Hannah C Sung
- Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Olivia Kates
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Department of Population Health, NYU Grossman School of Medicine, New York, New York, USA
| | - Jeremy Sugarman
- Department of Health Policy and Management, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Berman Institute of Bioethics, Johns Hopkins University, Baltimore, Maryland, USA
| | - Christine M Durand
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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Strauss AT, Sidoti CN, Sung HC, Jain VS, Lehmann H, Purnell TS, Jackson JW, Malinsky D, Hamilton JP, Garonzik-Wang J, Gray SH, Levan ML, Hinson JS, Gurses AP, Gurakar A, Segev DL, Levin S. Artificial intelligence-based clinical decision support for liver transplant evaluation and considerations about fairness: A qualitative study. Hepatol Commun 2023; 7:e0239. [PMID: 37695082 PMCID: PMC10497243 DOI: 10.1097/hc9.0000000000000239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 06/28/2023] [Indexed: 09/12/2023] Open
Abstract
BACKGROUND The use of large-scale data and artificial intelligence (AI) to support complex transplantation decisions is in its infancy. Transplant candidate decision-making, which relies heavily on subjective assessment (ie, high variability), provides a ripe opportunity for AI-based clinical decision support (CDS). However, AI-CDS for transplant applications must consider important concerns regarding fairness (ie, health equity). The objective of this study was to use human-centered design methods to elicit providers' perceptions of AI-CDS for liver transplant listing decisions. METHODS In this multicenter qualitative study conducted from December 2020 to July 2021, we performed semistructured interviews with 53 multidisciplinary liver transplant providers from 2 transplant centers. We used inductive coding and constant comparison analysis of interview data. RESULTS Analysis yielded 6 themes important for the design of fair AI-CDS for liver transplant listing decisions: (1) transparency in the creators behind the AI-CDS and their motivations; (2) understanding how the AI-CDS uses data to support recommendations (ie, interpretability); (3) acknowledgment that AI-CDS could mitigate emotions and biases; (4) AI-CDS as a member of the transplant team, not a replacement; (5) identifying patient resource needs; and (6) including the patient's role in the AI-CDS. CONCLUSIONS Overall, providers interviewed were cautiously optimistic about the potential for AI-CDS to improve clinical and equitable outcomes for patients. These findings can guide multidisciplinary developers in the design and implementation of AI-CDS that deliberately considers health equity.
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Affiliation(s)
- Alexandra T. Strauss
- Department of Medicine, Johns Hopkins University, School of Medicine, Baltimore, Maryland, USA
| | - Carolyn N. Sidoti
- Department of Surgery, New York University, Grossman School of Medicine, New York, New York, USA
| | - Hannah C. Sung
- Department of Surgery, Johns Hopkins University, School of Medicine, Baltimore, Maryland, USA
| | - Vedant S. Jain
- Department of Surgery, Johns Hopkins University, School of Medicine, Baltimore, Maryland, USA
| | - Harold Lehmann
- Department of Medicine, Division of Biomedical Informatics & Data Science, School of Medicine, Baltimore, Maryland, USA
| | - Tanjala S. Purnell
- Department of Epidemiology, Johns Hopkins University, Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - John W. Jackson
- Department of Epidemiology, Johns Hopkins University, Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Daniel Malinsky
- Department of Biostatistics, Columbia University Mailman School of Public Health, New York, New York, USA
| | - James P. Hamilton
- Department of Medicine, Johns Hopkins University, School of Medicine, Baltimore, Maryland, USA
| | - Jacqueline Garonzik-Wang
- Department of Surgery, University of Wisconsin, School of Medicine and Public Health, Madison, Wisconsin
| | - Stephen H. Gray
- Department of Surgery, University of Maryland, School of Medicine, Baltimore, Maryland, USA
| | - Macey L. Levan
- Department of Surgery, New York University, Grossman School of Medicine, New York, New York, USA
| | - Jeremiah S. Hinson
- Department of Emergency Medicine, Johns Hopkins University, School of Medicine, Baltimore, Maryland, USA
| | - Ayse P. Gurses
- Department of Anesthesiology and Critical Care Medicine, School of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Ahmet Gurakar
- Department of Medicine, Johns Hopkins University, School of Medicine, Baltimore, Maryland, USA
| | - Dorry L. Segev
- Department of Surgery, New York University, Grossman School of Medicine, New York, New York, USA
| | - Scott Levin
- Department of Emergency Medicine, Johns Hopkins University, School of Medicine, Baltimore, Maryland, USA
- Beckman Coulter, Brea, California, USA
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4
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Strauss AT, Sidoti CN, Purnell TS, Sung HC, Jackson JW, Levin S, Jain VS, Malinsky D, Segev DL, Hamilton JP, Garonzik‐Wang J, Gray SH, Levan ML, Scalea JR, Cameron AM, Gurakar A, Gurses AP. Multicenter study of racial and ethnic inequities in liver transplantation evaluation: Understanding mechanisms and identifying solutions. Liver Transpl 2022; 28:1841-1856. [PMID: 35726679 PMCID: PMC9796377 DOI: 10.1002/lt.26532] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 05/15/2022] [Accepted: 06/06/2022] [Indexed: 01/02/2023]
Abstract
Racial and ethnic disparities persist in access to the liver transplantation (LT) waiting list; however, there is limited knowledge about underlying system-level factors that may be responsible for these disparities. Given the complex nature of LT candidate evaluation, a human factors and systems engineering approach may provide insights. We recruited participants from the LT teams (coordinators, advanced practice providers, physicians, social workers, dieticians, pharmacists, leadership) at two major LT centers. From December 2020 to July 2021, we performed ethnographic observations (participant-patient appointments, committee meetings) and semistructured interviews (N = 54 interviews, 49 observation hours). Based on findings from this multicenter, multimethod qualitative study combined with the Systems Engineering Initiative for Patient Safety 2.0 (a human factors and systems engineering model for health care), we created a conceptual framework describing how transplant work system characteristics and other external factors may improve equity in the LT evaluation process. Participant perceptions about listing disparities described external factors (e.g., structural racism, ambiguous national guidelines, national quality metrics) that permeate the LT evaluation process. Mechanisms identified included minimal transplant team diversity, implicit bias, and interpersonal racism. A lack of resources was a common theme, such as social workers, transportation assistance, non-English-language materials, and time (e.g., more time for education for patients with health literacy concerns). Because of the minimal data collection or center feedback about disparities, participants felt uncomfortable with and unadaptable to unwanted outcomes, which perpetuate disparities. We proposed transplant center-level solutions (i.e., including but not limited to training of staff on health equity) to modifiable barriers in the clinical work system that could help patient navigation, reduce disparities, and improve access to care. Our findings call for an urgent need for transplant centers, national societies, and policy makers to focus efforts on improving equity (tailored, patient-centered resources) using the science of human factors and systems engineering.
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Affiliation(s)
- Alexandra T. Strauss
- Department of MedicineSchool of Medicine, Johns Hopkins UniversityBaltimoreMarylandUSA,Malone Center for Engineering in HealthcareWhiting School of Engineering, Johns Hopkins UniversityBaltimoreMarylandUSA
| | - Carolyn N. Sidoti
- Department of SurgerySchool of Medicine, Johns Hopkins UniversityBaltimoreMarylandUSA
| | - Tanjala S. Purnell
- Department of SurgerySchool of Medicine, Johns Hopkins UniversityBaltimoreMarylandUSA,Department of EpidemiologyBloomberg School of Public, Health Johns Hopkins UniversityBaltimoreMarylandUSA
| | - Hannah C. Sung
- Department of SurgerySchool of Medicine, Johns Hopkins UniversityBaltimoreMarylandUSA
| | - John W. Jackson
- Department of EpidemiologyBloomberg School of Public, Health Johns Hopkins UniversityBaltimoreMarylandUSA
| | - Scott Levin
- Malone Center for Engineering in HealthcareWhiting School of Engineering, Johns Hopkins UniversityBaltimoreMarylandUSA,Department of Emergency MedicineSchool of Medicine, Johns Hopkins UniversityBaltimoreMarylandUSA
| | - Vedant S. Jain
- Department of SurgerySchool of Medicine, Johns Hopkins UniversityBaltimoreMarylandUSA
| | - Daniel Malinsky
- Department of BiostatisticsColumbia University Mailman School of Public HealthNew YorkNew YorkUSA
| | - Dorry L. Segev
- Department of SurgerySchool of Medicine, Johns Hopkins UniversityBaltimoreMarylandUSA,Department of EpidemiologyBloomberg School of Public, Health Johns Hopkins UniversityBaltimoreMarylandUSA
| | - James P. Hamilton
- Department of MedicineSchool of Medicine, Johns Hopkins UniversityBaltimoreMarylandUSA
| | | | - Stephen H. Gray
- Department of SurgerySchool of Medicine, University of MarylandBaltimoreMarylandUSA
| | - Macey L. Levan
- Department of SurgerySchool of Medicine, Johns Hopkins UniversityBaltimoreMarylandUSA
| | - Joseph R. Scalea
- Department of SurgerySchool of Medicine, University of MarylandBaltimoreMarylandUSA
| | - Andrew M. Cameron
- Department of SurgerySchool of Medicine, Johns Hopkins UniversityBaltimoreMarylandUSA
| | - Ahmet Gurakar
- Department of MedicineSchool of Medicine, Johns Hopkins UniversityBaltimoreMarylandUSA
| | - Ayse P. Gurses
- Department of Emergency MedicineSchool of Medicine, Johns Hopkins UniversityBaltimoreMarylandUSA,Center for Health Care Human FactorsArmstrong Institute for Patient Safety and Quality, Johns Hopkins MedicineBaltimoreMarylandUSA,Anesthesiology and Critical Care Medicine, Biomedical Informatics and Data Science (General Internal Medicine)School of Medicine, Johns Hopkins UniversityBaltimoreMarylandUSA,Department of Health Policy and ManagementBloomberg School of Public Health, Johns Hopkins UniversityBaltimoreMarylandUSA
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5
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Ferzola A, Uriarte J, Sung HC, Anderson N, Sidoti C, Van Pilsum Rasmussen SE, Downey M, Vanterpool KB, Langlee W, Klitenic S, Young L, Cooney CM, Johnson I, Coleman A, Shores JT, Segev DL, Brandacher G, Gordon EJ, Levan ML. Public Perceptions and Information Needs of VCA Transplantation and Donation: A Mixed Methods Study. Transpl Int 2022; 35:10752. [PMID: 36451683 PMCID: PMC9701711 DOI: 10.3389/ti.2022.10752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Accepted: 10/27/2022] [Indexed: 11/15/2022]
Abstract
Vascularized Composite Allotransplantation (VCA) involves transplantation of multiple tissues from a donor to a recipient (e.g., skin, muscle, bone). Little is known about the US public’s perceptions of and attitudes toward VCA organ donation. This multi-site, cross-sectional, mixed methods study involved focus groups and surveys to assess members of the general public’s attitudes about VCA, and willingness and barriers to donate VCA organs. Qualitative data were analyzed by thematic analysis; quantitative data were analyzed by descriptive statistics. In focus groups (n = 6, 42 participants), most participants were female (57%) and Black (62%) with mean age of 42.6 years. Three main themes emerged: 1) awareness and perceptions of VCA, 2) purpose of VCA donation, 3) and barriers to VCA donation. Participants had heard little about VCA and sought information about VCA donation. Participants perceived VCA as challenging their concepts of “normality” and voiced concerns that VCA would create “Frankenstein[s].” Barriers to VCA donation included disruptions to end-of-life arrangements and information gaps regarding the donation process. Participants reported moderate to high willingness to donate their hands (69%) and face (50%) Public education efforts should address the specific needs and concerns of the public to facilitate VCA donation and family authorization.
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Affiliation(s)
- Alexander Ferzola
- Department of Surgery, School of Medicine, Johns Hopkins Medicine, Baltimore, MD, United States
| | - Jefferson Uriarte
- Center for Health Services and Outcomes Research, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | - Hannah C. Sung
- Department of Surgery, School of Medicine, Johns Hopkins Medicine, Baltimore, MD, United States
| | - Naomi Anderson
- Center for Health Services and Outcomes Research, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | - Carolyn Sidoti
- Department of Surgery, Grossman School of Medicine, New York University, New York, NY, United States
| | | | - Max Downey
- Department of Surgery, Grossman School of Medicine, New York University, New York, NY, United States
| | - Karen B. Vanterpool
- Department of Surgery, Grossman School of Medicine, New York University, New York, NY, United States
| | - Whitney Langlee
- Department of Surgery, School of Medicine, Johns Hopkins Medicine, Baltimore, MD, United States
| | - Samantha Klitenic
- Department of Surgery, Grossman School of Medicine, New York University, New York, NY, United States
| | - Lisa Young
- Department of Surgery, School of Medicine, Johns Hopkins Medicine, Baltimore, MD, United States
| | - Carisa M. Cooney
- Department of Plastic and Reconstructive Surgery, School of Medicine, Johns Hopkins Medicine, Baltimore, MD, United States
| | - Ieesha Johnson
- The Living Legacy Foundation, Organ Procurement Organization, Halethorpe, MD, United States
| | - Allison Coleman
- The Living Legacy Foundation, Organ Procurement Organization, Halethorpe, MD, United States
| | - Jaimie T. Shores
- Department of Plastic and Reconstructive Surgery, School of Medicine, Johns Hopkins Medicine, Baltimore, MD, United States
| | - Dorry L. Segev
- Department of Surgery, School of Medicine, Johns Hopkins Medicine, Baltimore, MD, United States
- Department of Surgery, Grossman School of Medicine, New York University, New York, NY, United States
| | - Gerald Brandacher
- Department of Plastic and Reconstructive Surgery, School of Medicine, Johns Hopkins Medicine, Baltimore, MD, United States
| | - Elisa J. Gordon
- Center for Health Services and Outcomes Research, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
- Department of Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | - Macey L. Levan
- Department of Surgery, School of Medicine, Johns Hopkins Medicine, Baltimore, MD, United States
- Department of Surgery, Grossman School of Medicine, New York University, New York, NY, United States
- *Correspondence: Macey L. Levan,
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6
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Al Ammary F, Motter JD, Sung HC, Lentine KL, Sharfuddin A, Kumar V, Yadav A, Doshi MD, Virmani S, Concepcion BP, Grace T, Sidoti CN, Yahya Jan M, Muzaale AD, Wolf J. Telemedicine services for living kidney donation: A US survey of multidisciplinary providers. Am J Transplant 2022; 22:2041-2051. [PMID: 35575439 PMCID: PMC9543040 DOI: 10.1111/ajt.17093] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 04/13/2022] [Accepted: 05/08/2022] [Indexed: 01/25/2023]
Abstract
Individuals considering living kidney donation face geographic, financial, and logistical challenges. Telemedicine can facilitate healthcare access/care coordination. Yet difficulties exist in telemedicine implementation and sustainability. We sought to examine centers' practices and providers' attitudes toward telemedicine to improve services for donors. We surveyed multidisciplinary providers from 194 active adult US living donor kidney transplant centers; 293 providers from 128 unique centers responded to the survey (center representation rate = 66.0%), reflecting 83.9% of practice by donor volume and 91.5% of US states/territories. Most centers (70.3%) plan to continue using telemedicine beyond the pandemic for donor evaluation/follow-up. Video was mostly used by nephrologists, surgeons, and psychiatrists/psychologists. Telephone and video were mostly used by social workers, while video or telephone was equally used by coordinators. Half of respondent nephrologists and surgeons were willing to accept a remote completion of physical exam; 68.3% of respondent psychiatrists/psychologists and social workers were willing to accept a remote completion of mental status exam. Providers strongly agreed that telemedicine was convenient for donors and would improve the likelihood of completing donor evaluation. However, providers (65.5%) perceived out-of-state licensing as a key policy/regulatory barrier. These findings help inform practice and underscore the instigation of policies to remove barriers using telemedicine to increase living kidney donation.
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Affiliation(s)
- Fawaz Al Ammary
- Department of MedicineJohns Hopkins UniversityBaltimoreMarylandUSA
| | | | - Hannah C. Sung
- Department of SurgeryJohns Hopkins UniversityBaltimoreMarylandUSA
| | | | - Asif Sharfuddin
- Department of MedicineIndiana UniversityIndianapolisIndianaUSA
| | - Vineeta Kumar
- Department of MedicineUniversity of AlabamaBirminghamAlabamaUSA
| | - Anju Yadav
- Department of MedicineThomas Jefferson UniversityPhiladelphiaPennsylvaniaUSA
| | - Mona D. Doshi
- Department of MedicineUniversity of MichiganAnn ArborMichiganUSA
| | - Sarthak Virmani
- Department of MedicineYale UniversityNew HavenConnecticutUSA
| | | | - Terry Grace
- Department of MedicineWake Forest Baptist HealthWinston‐SalemNorth CarolinaUSA
| | | | | | | | - Joshua Wolf
- Piedmont Transplant InstituteAtlantaGeorgiaUSA
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7
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Funderburg NT, Stubblefield Park SR, Sung HC, Hardy G, Clagett B, Ignatz-Hoover J, Harding CV, Fu P, Katz JA, Lederman MM, Levine AD. Circulating CD4(+) and CD8(+) T cells are activated in inflammatory bowel disease and are associated with plasma markers of inflammation. Immunology 2013; 140:87-97. [PMID: 23600521 DOI: 10.1111/imm.12114] [Citation(s) in RCA: 111] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2012] [Revised: 03/19/2013] [Accepted: 04/11/2013] [Indexed: 12/13/2022] Open
Abstract
Inflammatory bowel disease (IBD) is characterized by damage to the gut mucosa and systemic inflammation. We sought to evaluate the role of chronic inflammation on circulating T-cell activation in human subjects with Crohn's disease and ulcerative colitis. We studied 54 patients with IBD and 28 healthy controls. T-cell activation and cycling were assessed in whole blood samples by flow cytometry. Levels of lipopolysaccharide (LPS) were measured in serum by Limulus amoebocyte lysate assay, and plasma levels of inflammatory markers and LPS-binding proteins were measured by ELISA. The proportions of circulating CD4(+) and CD8(+) T lymphocytes in cycle (Ki67(+) ) are increased in patients with IBD compared with these proportions in controls. CD8(+) T cells from patients with IBD are also enriched for cells that expressed CD38 and HLA-DR, and proportions of these cells are related to plasma levels of interleukin-6 and C-reactive protein in these patients. Intracellular interleukin-2 and interferon-γ levels were elevated in resting and polyclonally activated CD4(+) and CD8(+) T cells in patients with IBD when compared with levels from healthy controls. Surprisingly, we did not find increased levels of LPS in the serum of patients with IBD. We did, however, find a signature of recent microbial translocation, as levels of LPS-binding protein are increased in the plasma of patients with IBD compared with plasma levels in healthy controls; LPS-binding protein levels are also directly related to proportions of CD38 HLA-DR-expressing CD4(+) and CD8(+) T cells. Local damage to the gastrointestinal tract in IBD may result in systemic inflammation and T-cell activation.
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Affiliation(s)
- Nicholas T Funderburg
- Department of Medicine, School of Medicine, Case Western Reserve University, Cleveland, OH 44106-4952, USA
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8
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Meisch JP, Nishimura M, Vogel RM, Sung HC, Bednarchik BA, Ghosh SK, Fu P, McCormick T, Weinberg A, Levine AD. Human β-defensin 3 peptide is increased and redistributed in Crohn's ileitis. Inflamm Bowel Dis 2013; 19:942-53. [PMID: 23511030 PMCID: PMC3746836 DOI: 10.1097/mib.0b013e318280b11a] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
BACKGROUND Antimicrobial peptides (AMPs) maintain a sterile environment in intestinal crypts, limiting microbial colonization and invasion. Decreased AMP expression is proposed to increase the risk for inflammatory bowel disease. Expression and function of inducible AMPs, human β-defensin 2 and 3 (hBD-2 and hBD-3), remain poorly characterized in healthy and chronically inflamed intestine. METHODS Peptide concentrations of hBD-2 and hBD-3 in serum and intestinal biopsies of subjects with ulcerative colitis and Crohn's disease (CD), and those of healthy subjects were measured by ELISA. Messenger RNA of hBD-2 and hBD-3 was quantified by quantitative PCR in biopsies from the terminal ileum (TI) of patients with CD and healthy controls. Peptide localization of hBD-3 in the TI was visualized by confocal microscopy. RESULTS Immunoreactive hBD-3 peptide is present in the TI and colon in healthy subjects. In the TI of patients with CD, hBD-3, but not hBD-2 peptide, is increased 4-fold, whereas hBD-2 peptide is elevated in the serum. Messenger RNA of hBD-3 in the CD TI remains unchanged and does not correlate with hBD-3 peptide expression. However, hBD-3 is localized to Paneth cell granules and the apical surface of the healthy columnar epithelium. In CD, hBD-3 peptide location switches to the basolateral surface of the columnar epithelium and is diffusely distributed within the lamina propria. CONCLUSION The peptide hBD-3 throughout the healthy gastrointestinal tract suggests a role in maintaining balance between host defenses and commensal microbiota. Increased and relocalized secretion of hBD-3 toward the lamina propria in the CD TI indicates possible local immunomodulation during chronic inflammation, whereas increased serum hBD-2 in CD implicates its systemic antimicrobial and immunomodulatory role.
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Affiliation(s)
- Jeffrey P. Meisch
- Department of Medicine, 10900 Euclid Avenue, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106
| | - Michiko Nishimura
- Department of Biological Sciences, Case Western Reserve University School of Dental Medicine, Cleveland, Ohio 44106
| | - Ryan M. Vogel
- Department of Medicine, 10900 Euclid Avenue, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106
| | - Hannah C. Sung
- Department of Medicine, 10900 Euclid Avenue, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106
| | - Beth A. Bednarchik
- Department of Medicine, 10900 Euclid Avenue, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106
| | - Santosh K. Ghosh
- Department of Biological Sciences, Case Western Reserve University School of Dental Medicine, Cleveland, Ohio 44106
| | - Pingfu Fu
- Department of Biostatistics, 10900 Euclid Avenue, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106
| | - Thomas McCormick
- Department of Dermatology, 10900 Euclid Avenue, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106
| | - Aaron Weinberg
- Department of Biological Sciences, Case Western Reserve University School of Dental Medicine, Cleveland, Ohio 44106
| | - Alan D. Levine
- Department of Medicine, 10900 Euclid Avenue, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106,Department of Pathology, Pharmacology, the Case Comprehensive Cancer Center, 10900 Euclid Avenue, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106,Address correspondence to: Alan D. Levine Ph.D., Department of Medicine, Case Western Reserve University School of Medicine BRB 525, 10900 Euclid Avenue, Cleveland, Ohio, 44106-4952. Phone: (216) 368-0342, Fax: (216) 368-0647,
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9
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Kweon MH, Hwang HJ, Sung HC. Identification and antioxidant activity of novel chlorogenic acid derivatives from bamboo (Phyllostachys edulis). J Agric Food Chem 2001; 49:4646-4655. [PMID: 11600002 DOI: 10.1021/jf010514x] [Citation(s) in RCA: 151] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
One known and two novel antioxidant compounds have been isolated from bamboo (Phyllostachys edulis). The butanol-soluble extract of the bamboo leaves was found to have a significant antioxidant activity, as measured by scavenging the stable 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical and the superoxide anion radical (O(2)(-)) in the xanthine/xanthine oxidase assay system. Antioxidant activity-directed fractionation of the extract led to the isolation and characterization of three structural isomeric chlorogenic acid derivatives: 3-O-(3'-methylcaffeoyl)quinic acid (1), 5-O-caffeoyl-4-methylquinic acid (2), and 3-O-caffeoyl-1-methylquinic acid (3). Compounds 2 and 3 were isolated and characterized for the first time from the natural products. In the DPPH scavenging assay as well as in the iron-induced rat microsomal lipid peroxidation system, compounds 2 (IC(50) = 8.8 and 19.2 microM) and 3 (IC(50) = 6.9 and 14.6 microM) showed approximately 2-4 times higher antioxidant activity than did chlorogenic acid (IC(50) = 12.3 and 28.3 microM) and other related hydroxycinnamates such as caffeic acid (IC(50) =13.7 and 25.5 microM) and ferulic acid (IC(50) = 36.5 and 56.9 microM). Among the three compounds, compound 1 yielded the weakest antioxidant activity, and the DPPH scavenging and lipid peroxidation inhibitory activity (IC(50) = 16.0 and 29.8 microM) was lower than those of chlorogenic and caffeic acids. All three compounds exhibited both superoxide scavenging activities and inhibitory effects on xanthine oxidase. Their superoxide anion (O(2)(-)) scavenging activities (IC(50) = 1, 4.3 microM; 2, 2.8 microM; and 3, 1.2 microM) were markedly stronger than those of ascorbic acid (IC(50) = 56.0 microM), alpha-tocopherol (IC(50) > 100 microM), and other test compounds, although their inhibition effects on xanthine oxidase may contribute to the potent scavenging activity. alpha-Tocopherol exerted a significant inhibitory effect (65.5% of the control) on superoxide generation in 12-O-tetradecanoylphorbol-13-acetate-induced human promyelocytic leukemia HL-60 cells, and compound 3 showed moderate activity (36.0%). On the other hand, other compounds including 1, 2, chlorogenic acid, and other antioxidants were weakly active (24.8-10.1%) in the suppression of superoxide generation.
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Affiliation(s)
- M H Kweon
- Graduate School of Biotechnology, Korea University, 5-1 ka Anam-dong, Sungbuk-ku, Seoul 136-701, Korea
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10
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Abstract
PURPOSE To enhance in vitro and in vivo transfection activity by optimizing lipid composition of cationic lipid emulsions. METHODS Various emulsion formulations having different cationic lipids as emulsifiers, and additional helper lipids as co-emulsifiers, were prepared. The stability of the emulsion and its complex with DNA was investigated by measuring the particle size change in phosphate buffer saline (PBS) over a period of 20 days. The activity of the emulsions in transfecting pCMV-beta into COS-1 cells in the presence or absence of 80% serum was evaluated. We also evaluated in vivo transfection activity using intravenously administered pCMV-Luc+ as a reporter gene. RESULTS Among the cationic emulsifiers, 1,2-dioleoyl-sn-glycero-3-trimethylammonium-propane (DOTAP) formed the most stable and efficient emulsion gene carrier. Addition of 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) increased in vitro transfection activity, but slightly compromised the stability of the emulsion. The loss was compensated for by including small amounts of Tween 80 in the emulsion. The in vitro and in vivo transfection activities were also increased by adding Tween 80. Even though in vitro transfection activity of liposomes was high in the absence of serum, the transfection activity of emulsions was far greater than that of liposomes in the presence of serum and for in vivo applications. CONCLUSIONS By including DOPE as an endosomolytic agent and Tween 80 as a stabilization agent, the cationic emulsion becomes a more potent gene carrier for in vitro and in vivo applications, especially in the presence of serum.
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Affiliation(s)
- T W Kim
- Biomedical Research Center, Korea Institute of Science and Technology, Seoul
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11
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Lee S, Yoon J, Park B, Jun Y, Jin M, Sung HC, Kim IH, Kang S, Choi EJ, Ahn BY, Ahn K. Structural and functional dissection of human cytomegalovirus US3 in binding major histocompatibility complex class I molecules. J Virol 2000; 74:11262-9. [PMID: 11070025 PMCID: PMC113228 DOI: 10.1128/jvi.74.23.11262-11269.2000] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The human cytomegalovirus US3, an endoplasmic reticulum (ER)-resident transmembrane glycoprotein, forms a complex with major histocompatibility complex (MHC) class I molecules and retains them in the ER, thereby preventing cytolysis by cytotoxic T lymphocytes. To identify which parts of US3 confine the protein to the ER and which parts are responsible for the association with MHC class I molecules, we constructed truncated mutant and chimeric forms in which US3 domains were exchanged with corresponding domains of CD4 and analyzed them for their intracellular localization and the ability to associate with MHC class I molecules. All of the truncated mutant and chimeric proteins containing the luminal domain of US3 were retained in the ER, while replacement of the US3 luminal domain with that of CD4 led to cell surface expression of the chimera. Thus, the luminal domain of US3 was sufficient for ER retention. Immunolocalization of the US3 glycoprotein after nocodazole treatment and the observation that the carbohydrate moiety of the US3 glycoprotein was not modified by Golgi enzymes indicated that the ER localization of US3 involved true retention, without recycling through the Golgi. Unlike the ER retention signal, the ability to associate with MHC class I molecules required the transmembrane domain in addition to the luminal domain of US3. Direct interaction between US3 and MHC class I molecules could be demonstrated after in vitro translation by coimmunoprecipitation. Together, the present data indicate that the properties that allow US3 to be localized in the ER and bind MHC class I molecules are located in different parts of the molecule.
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Affiliation(s)
- S Lee
- Graduate School of Biotechnology, Korea University, Seoul 136-701, Korea
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12
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Abstract
We evaluate a new cationic emulsion as a mucosal gene carrier and elucidate the relationship between the transfection efficiency and the stability of the carrier/DNA complex. A cationic lipid emulsion was formulated with soybean oil and 1,2-dioleoyl-sn-glycero-3-trimethylammonium-propane (DOTAP) as major components and was used to transfer genes to the epithelial cells of the mouse nasal cavity via intranasal instillation. Correlation between the transfection efficiency and the stability of the carrier/DNA complex was investigated by measuring the carrier size changes and by observing the degree of DNA protection against DNase I digestion in the presence of heparin. The cationic emulsion showed at least 3 times better transfection activity than the liposomal carriers in nasal mucosae. The cationic emulsion was stable in the presence of heparin whereas the liposomal carriers became very unstable. Unlike DNA in liposome/DNA complexes, DNA in the emulsion/DNA complex was resistant to heparin exchange and DNase I digestion. The cationic emulsion was more effective in delivering DNA to nasal mucosae than commercially available liposomal carriers. The transfection activities of the lipid carriers in nasal cavity mucosae are in agreement with the stability of the lipid carriers and their complexes with DNA.
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Affiliation(s)
- T W Kim
- Biomedical Research Center, Korea Institute of Science and Technology, Seoul
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13
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Jun Y, Kim E, Jin M, Sung HC, Han H, Geraghty DE, Ahn K. Human cytomegalovirus gene products US3 and US6 down-regulate trophoblast class I MHC molecules. J Immunol 2000; 164:805-11. [PMID: 10623826 DOI: 10.4049/jimmunol.164.2.805] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The epidemiological correlation between human CMV (HCMV) infection and spontaneous fetal loss has been suggested, but the underlying mechanism is not well understood. Fetal cytotrophoblasts, which are in direct contact with the maternal immune system in the uterus during pregnancy, do not express HLA-A and HLA-B, but express the nonclassical class I HLA-G and HLA-C. It has been shown that both HLA-G and HLA-C are capable of inhibiting NK-mediated cell lysis. In our present study, using human trophoblast cell lines as well as other cell lines stably transfected with the human class I genes, we have demonstrated that HCMV US3 and US6 down-regulate the cell-surface expression of both HLA-G and HLA-C by two different mechanisms. HCMV US3 physically associates with both trophoblast class I MHC species, retaining them in the endoplasmic reticulum. In contrast, HCMV US6 inhibits peptide transport by TAP and thus specifically the intracellular trafficking of class I molecules. Therefore, these findings suggest for the first time a possible molecular mechanism underlying HCMV-related spontaneous pregnancy loss.
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Affiliation(s)
- Y Jun
- Graduate School of Biotechnology, Korea University, Seoul, Korea
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14
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Hwang KY, Cho CS, Kim SS, Sung HC, Yu YG, Cho Y. Structure and mechanism of glutamate racemase from Aquifex pyrophilus. Nat Struct Biol 1999; 6:422-6. [PMID: 10331867 DOI: 10.1038/8223] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Glutamate racemase (MurI) is responsible for the synthesis of D-glutamate, an essential building block of the peptidoglycan layer in bacterial cell walls. The crystal structure of glutamate racemase from Aquifex pyrophilus, determined at 2.3 A resolution, reveals that the enzyme forms a dimer and each monomer consists of two alpha/beta fold domains, a unique structure that has not been observed in other racemases or members of an enolase superfamily. A substrate analog, D-glutamine, binds to the deep pocket formed by conserved residues from two monomers. The structural and mutational analyses allow us to propose a mechanism of metal cofactor-independent glutamate racemase in which two cysteine residues are involved in catalysis.
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Affiliation(s)
- K Y Hwang
- Structural Biology Center, Korea Institute of Science and Technology, Seoul, South Korea
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15
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Kim SY, Hwang KY, Kim SH, Sung HC, Han YS, Cho Y. Structural basis for cold adaptation. Sequence, biochemical properties, and crystal structure of malate dehydrogenase from a psychrophile Aquaspirillium arcticum. J Biol Chem 1999; 274:11761-7. [PMID: 10206992 DOI: 10.1074/jbc.274.17.11761] [Citation(s) in RCA: 124] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Aquaspillium arcticum is a psychrophilic bacterium that was isolated from arctic sediment and grows optimally at 4 degrees C. We have cloned, purified, and characterized malate dehydrogenase from A. arcticum (Aa MDH). We also have determined the crystal structures of apo-Aa MDH, Aa MDH.NADH binary complex, and Aa MDH.NAD.oxaloacetate ternary complex at 1.9-, 2.1-, and 2.5-A resolutions, respectively. The Aa MDH sequence is most closely related to the sequence of a thermophilic MDH from Thermus flavus (Tf MDH), showing 61% sequence identity and over 90% sequence similarity. Stability studies show that Aa MDH has a half-life of 10 min at 55 degrees C, whereas Tf MDH is fully active at 90 degrees C for 1 h. Aa MDH shows 2-3-fold higher catalytic efficiency compared with a mesophilic or a thermophilic MDH at the temperature range 4-10 degrees C. Structural comparison of Aa MDH and Tf MDH suggests that the increased relative flexibility of active site residues, favorable surface charge distribution for substrate and cofactor, and the reduced intersubunit ion pair interactions may be the major factors for the efficient catalytic activity of Aa MDH at low temperatures.
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Affiliation(s)
- S Y Kim
- Structural Biology Center, Korea Institute of Science and Technology, P.O. Box 131, Cheongryang, Seoul 130-650, South Korea
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Bae KW, Baek KW, Cho CS, Hwang KY, Kim HR, Sung HC, Cho Y. Expression, purification, characterization and crystallization of flap endonuclease-1 from Methanococcus jannaschii. Mol Cells 1999; 9:45-8. [PMID: 10102570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
Abstract
A gene coding for a protein homologous to the flap endonuclease-1 (FEN-1) was cloned from Methanococcus jannaschii, overexpressed, purified and characterized. The gene product from M. jannaschii shows 5' endo-/exonuclease and 5' pseudo-Y-endonuclease activities as observed in the FEN-1 in eukaryotes. In addition, Methanococcus jannaschii FEN-1 functions effectively at high concentrations of salt, unlike eukaryotic FEN-1. We have crystallized Methanococcus jannaschii FEN-1 and analyzed its preliminary character. The crystal belongs to the space group of P2(1) with unit cell dimensions of a = 58.93 A, b = 42.53 A, c = 62.62 A and beta = 92.250. A complete data set has been collected at 2.0 A resolution using a frozen crystal.
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Affiliation(s)
- K W Bae
- Structural Biology Center, Korea Institute of Science & Technology, Seoul
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Chang IS, Kim BH, Kim DH, Lovitt RW, Sung HC. Formulation of defined media for carbon monoxide fermentation by Eubacterium limosum KIST612 and the growth characteristics of the bacterium. J Biosci Bioeng 1999; 88:682-5. [PMID: 16232686 DOI: 10.1016/s1389-1723(00)87102-9] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/1999] [Accepted: 08/23/1999] [Indexed: 11/21/2022]
Abstract
Phosphate-buffered (PBBM) and carbonate-buffered (CBBM) basal media were used in the formulation of defined media for the cultivation of Eubacterium limosum KIST612 with carbon monoxide (CO) as the sole energy source. The bacterium was adapted to the minimal media by sequential passage in media containing casamino acids and those containing ammonium chloride in the place of yeast extract. Biological growth was slower with a lower growth yield in the defined minimal media than in PBBM or CBBM. More butyrate was produced in phosphate-buffered media than in carbonate-buffered media. The bacteria grew without any organic nitrogen in the presence of trace quantities of biotin and pantothenic acid. Anaerobic digester fluid stimulated bacterial growth.
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Affiliation(s)
- I S Chang
- Water Environment Research Center, Korea Institute of Science and Technology, Seoul 136-791, Korea
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Huh TL, Ryu JH, Huh JW, Sung HC, Oh IU, Song BJ, Veech RL. Cloning of a cDNA encoding bovine mitochondrial NADP(+)-specific isocitrate dehydrogenase and structural comparison with its isoenzymes from different species. Biochem J 1993; 292 ( Pt 3):705-10. [PMID: 8318002 PMCID: PMC1134171 DOI: 10.1042/bj2920705] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Mitochondrial NADP(+)-specific isocitrate dehydrogenase (IDP) was co-purified with the pyruvate dehydrogenase complex from bovine kidney mitochondria. The determination of its N-terminal 16-amino-acid sequence revealed that it is highly similar to the IDP from yeast. A cDNA clone (1.8 kb long) encoding this protein was isolated from a bovine kidney lambda gt11 cDNA library using a synthetic oligodeoxynucleotide. The deduced protein sequence of this cDNA clone rendered a precursor protein of 452 amino-acid residues (50,830 Da) and a mature protein of 413 amino-acid residues (46,519 Da). It is 100% identical to the internal tryptic peptide sequences of the autologous form from pig heart and 62% similar to that from yeast. However, it shares little similarity with the mitochondrial NAD(+)-specific isoenzyme from yeast. Structural analyses of the deduced proteins of IDP isoenzymes from different species indicated that similarity exists in certain regions, which may represent the common domains for the active sites or coenzyme-binding sites. In Northern-blot analysis, one species of mRNA (about 2.2 kb for both bovine and human) was hybridized with a 32P-labelled cDNA probe. Southern-blot analysis of genomic DNAs verified simple patterns of hybridization with this cDNA. These results strongly indicate that the mitochondrial IDP may be derived from a single gene family which does not appear to be closely related to that of the NAD(+)-specific isoenzyme.
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Affiliation(s)
- T L Huh
- Department of Genetic Engineering, College of Natural Sciences, Kyungpook National University, Taegu, Korea
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Wakisaka S, Tachiki T, Sung HC, Kumagai H, Tochikura T, Matsui S. A rapid assay method for ammonia using glutamine synthetase from glutamate-producing bacteria. Anal Biochem 1987; 163:117-22. [PMID: 2887129 DOI: 10.1016/0003-2697(87)90101-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
A rapid enzymatic assay method for ammonia was developed by using glutamine synthetase from glutamate-producing bacteria together with pyruvate kinase, lactate dehydrogenase, and NADH. The time required for determination of 25 nmol of ammonia was 5 min with 1 unit of glutamine synthetase, as opposed to 14-30 min with 1 unit of glutamate dehydrogenases from various sources. The present method was used to determine ammonia in serum, microbiol-culture broth, and waste water. The method can be modified for spectrophotometry in the visible region by substituting pyruvate oxidase, peroxidase, and appropriate chromogens for lactate dehydrogenase and NADH. With 4-aminoantipyrine (4AA) and phenol, and with 4AA and N-ethyl-N-2-hydroxyethyl-m-toluidine as chromogens, the sensitivity of ammonia determination was 0.65 and 1.7 times that with glutamate dehydrogenase, respectively. The present method was also applicable to the continuous detection of the activity of some ammonia-forming enzymes such as guanase, adenosine deaminase, and urease and to the determination of 0.5-30 microM ATP-ADP after some modification of the mixture.
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Wu PC, Brinton LA, Wang W, Sung HC, Ershow AG, Li JY, Blot WJ. A case-control study of trophoblastic diseases in the People's Republic of China. Natl Cancer Inst Monogr 1985; 69:15-8. [PMID: 3010120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
A case-control study is currently under way in Beijing, People's Republic of China, involving approximately 165 patients with invasive moles or choriocarcinoma, 165 with hydatidiform moles, and 330 population controls, who were matched to the patients with invasive moles or choriocarcinoma on age and interval since last pregnancy. The interviews are focused on a number of suspected risk factors, including previous pregnancy outcomes, history of hydatidiform mole, medical factors, drug usage, family history, and diet. A brief background of the study and methods as established through a previous pilot study are given.
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Abstract
Large dosage of 5-fluorouracil given by slow intravenous infusion has proved to be very effective in the treatment of gestational trophoblastic neoplasms. From 1965 through 1975, 5-fluorouracil was used as a single chemotherapeutic agent in 173 cases of invasive mole and 139 cases of choriocarcinoma. Complete remission was achieved in 84.9% of cases of invasive mole and in 59.3% of cases of choriocarcinoma when 5-fluorouracil was used as the initial treatment. Seven recurrences with three deaths occurred during follow-up in 216 patients who had achieved complete remission, providing a recurrence rate of 3.2% and recurrence death rate of 1.4%. All of the survivors were followed up for more than 5 years and 85.6% for more than 10 years. Toxicity of 5-fluorouracil was milder and less frequent than that of 6-mercaptopurine or methotrexate. The toxic reaction specific to 5-fluorouracil was diarrhea, which can result in pseudomembranous colitis if improperly treated. One of the two toxic deaths was due to this complication.
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Sung HC, Wu PC, Wang YB. Re-evaluation of 5-fluorouracil as a single agent for gestational malignant trophoblastic neoplasms. Adv Exp Med Biol 1984; 176:355-67. [PMID: 6093468 DOI: 10.1007/978-1-4684-4811-5_21] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Large doses of 5-fluorouracil, administered by slow intravenous drip, have proven to be very effective in the treatment of malignant trophoblastic tumors. From 1964 through 1975, 5-fluorouracil was used as a single chemotherapeutic agent in 173 cases of invasive mole and 139 cases of choriocarcinoma. This series of patients was further divided into Group A (212 cases) in which 5-fluorouracil was used as initial therapy, and Group B (100 cases) in which 5-fluorouracil was given to those who developed resistance to 6-mercaptopurine and/or to methotrexate. The overall remission rate in Group A patients was 98.4% for invasive mole and 93.0% for choriocarcinoma. In Group B patients the corresponding remission rate was 93.6% and 71.7%, respectively, indicating that 5-fluorouracil is effective in patients who develop resistance to other antimetabolic agents. The rate of recurrence among 213 patients achieving complete remission during follow-up was 1.4% (3 cases). All of the remaining 210 patients had survived for more than 5 years up to the end of 1981, and 96 patients (45.7%) had survived for more than 10 years. In comparison with other antimetabolites, 5-fluorouracil has the advantages of being more effective and less toxic, and can be administered through multiple routes. Therefore, it has remained the agent of first choice in the chemotherapy of malignant trophoblastic neoplasms.
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Sung HC, Wu PC, Wang YE, Tang MY, Yang HY. A proposal on the clinical staging of malignant trophoblastic neoplasms based on the study of process of development of the disease. Adv Exp Med Biol 1984; 176:327-40. [PMID: 6093466 DOI: 10.1007/978-1-4684-4811-5_19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Abstract
From 1949 to 1975, a total of 3,915 chest films were taken for 429 cases of choriocarcinoma and 441 cases of invasive mole. The incidences of pulmonary metastases were 85.1% and 65.0%, respectively. The various forms of pulmonary metastases were studied and correlated with clinical symptoms and pathologic changes. In order to follow up the progression or regression of the various forms, serial chest films were taken at intervals of 10 to 14 days in 27 cases. In eight cases postmortem pulmonary arteriograms were obtained on the autopsied lung specimens for the study of vascular changes of metastatic lesions. Pathologic examinations and pulmonary arteriography were also done on the surgically resected lung specimens. As a result of this study, a relative comprehensive knowledge about the nature and development of the various forms of metastatic shadows has been deduced. It is rational to say that the various forms seen on the chest films represent only the various evolutionary changes of the same lesion.
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