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Crothers JW, Chu ND, Nguyen LTT, Phillips M, Collins C, Fortner K, Del Rio-Guerra R, Lavoie B, Callas P, Velez M, Cohn A, Elliott RJ, Wong WF, Vo E, Wilcox R, Smith M, Kassam Z, Budd R, Alm EJ, Mawe GM, Moses PL. Daily, oral FMT for long-term maintenance therapy in ulcerative colitis: results of a single-center, prospective, randomized pilot study. BMC Gastroenterol 2021; 21:281. [PMID: 34238227 PMCID: PMC8268596 DOI: 10.1186/s12876-021-01856-9] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 06/23/2021] [Indexed: 02/22/2023] Open
Abstract
Background Fecal microbiota transplantation (FMT) is a promising new strategy in the treatment of Inflammatory Bowel Disease, but long-term delivery systems are lacking. This randomized study was designed as a safety and feasibility study of long-term FMT in subjects with mild to moderate UC using frozen, encapsulated oral FMT (cFMT). Methods Subjects were randomized 1:1 to receive FMT induction by colonoscopy, followed by 12 weeks of daily oral administration of frozen encapsulated cFMT or sham therpay. Subjects were followed for 36 weeks and longitudenal clinical assessments included multiple subjective and objective markers of disease severity. Ribosomal 16S bacterial sequencing was used to assess donor-induced changes in the gut microbiota. Changes in T regulatory (Treg) and mucosal associated invariant T (MAIT) cell populations were evaluated by flow cytometry as an exploratory endpoint. Results Twelve subjects with active UC were randomized: 6 subjects completed the full 12-week course of FMT plus cFMT, and 6 subjects received sham treatment by colonic installation and longitudinal oral placebo capules. Chronic administration of cFMT was found to be safe and well-tolerated but home storage concerns exist. Protocol adherence was high, and none of the study subjects experienced FMT-associated treatment emergent adverse events. Two subjects that received cFMT achieved clinical remission versus none in the placebo group (95% CI = 0.38-infinity, p = 0.45). cFMT was associated with sustained donor-induced shifts in fecal microbial composition. Changes in MAIT cell cytokine production were observed in cFMT recipients and correlated with treatment response. Conclusion These pilot data suggest that daily encapsulated cFMT may extend the durability of index FMT-induced changes in gut bacterial community structure and that an association between MAIT cell cytokine production and clinical response to FMT may exist in UC populations. Oral frozen encapsulated cFMT is a promising FMT delivery system and may be preferred for longterm treatment strategies in UC and other chronic diseases but further evaluations will have to address home storage concerns. Larger trials should be done to explore the benefits of cFMT and to determine its long-term impacts on the colonic microbiome. Trial registration: ClinicalTrials.gov (NCT02390726). Registered 17 March 2015, https://clinicaltrials.gov/ct2/show/NCT02390726?term=NCT02390726&draw=2&rank=1. Supplementary Information The online version contains supplementary material available at 10.1186/s12876-021-01856-9.
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Affiliation(s)
- Jessica W Crothers
- Department of Pathology and Laboratory Medicine, University of Vermont Medical Center, 111 Colchester Ave, Burlington, VT, 05401, USA. .,Larner College of Medicine, The University of Vermont, 89 Beaumont Ave, Burlington, VT, 05401, USA.
| | - Nathaniel D Chu
- Department of Biological Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA.,Center for Microbiome Informatics and Therapeutics, Broad Institute, Cambridge, MA, USA
| | - Le Thanh Tu Nguyen
- Department of Biological Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA.,Center for Microbiome Informatics and Therapeutics, Broad Institute, Cambridge, MA, USA
| | - Magen Phillips
- Department of Medicine, University of Vermont Medical Center, 111 Colchester Ave, Burlington, VT, 05401, USA
| | - Cheryl Collins
- Department of Medicine, University of Vermont Medical Center, 111 Colchester Ave, Burlington, VT, 05401, USA
| | - Karen Fortner
- Department of Medicine, University of Vermont Medical Center, 111 Colchester Ave, Burlington, VT, 05401, USA
| | - Roxana Del Rio-Guerra
- Flow Cytometry and Cell Sorting Facility, Department of Surgery, Larner College of Medicine, University of Vermont, 89 Beaumont Ave, Burlington, VT, 05401, USA
| | - Brigitte Lavoie
- Department of Neurological Sciences, Larner College of Medicine, University of Vermont, 89 Beaumont Ave, Burlington, VT, 05401, USA
| | - Peter Callas
- Department of Medical Biostatistics, University of Vermont, 89 Beaumont Ave, Burlington, VT, 05401, USA
| | - Mario Velez
- Department of Medicine, University of Vermont Medical Center, 111 Colchester Ave, Burlington, VT, 05401, USA
| | - Aaron Cohn
- Department of Medicine, University of Vermont Medical Center, 111 Colchester Ave, Burlington, VT, 05401, USA
| | - Ryan J Elliott
- OpenBiome, 2067 Massachusetts Ave, Cambridge, MA, 02140, USA
| | - Wing Fei Wong
- OpenBiome, 2067 Massachusetts Ave, Cambridge, MA, 02140, USA
| | - Elaine Vo
- Finch Therapeutics, 200 Inner Belt Rd, Somerville, MA, 02143, USA
| | - Rebecca Wilcox
- Department of Pathology and Laboratory Medicine, University of Vermont Medical Center, 111 Colchester Ave, Burlington, VT, 05401, USA.,Larner College of Medicine, The University of Vermont, 89 Beaumont Ave, Burlington, VT, 05401, USA
| | - Mark Smith
- Finch Therapeutics, 200 Inner Belt Rd, Somerville, MA, 02143, USA
| | - Zain Kassam
- Finch Therapeutics, 200 Inner Belt Rd, Somerville, MA, 02143, USA
| | - Ralph Budd
- Department of Medicine, University of Vermont Medical Center, 111 Colchester Ave, Burlington, VT, 05401, USA.,Larner College of Medicine, The University of Vermont, 89 Beaumont Ave, Burlington, VT, 05401, USA
| | - Eric J Alm
- Department of Biological Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA.,Center for Microbiome Informatics and Therapeutics, Broad Institute, Cambridge, MA, USA
| | - Gary M Mawe
- Department of Neurological Sciences, Larner College of Medicine, University of Vermont, 89 Beaumont Ave, Burlington, VT, 05401, USA
| | - Peter L Moses
- Larner College of Medicine, The University of Vermont, 89 Beaumont Ave, Burlington, VT, 05401, USA.,Finch Therapeutics, 200 Inner Belt Rd, Somerville, MA, 02143, USA
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Serrano-Villar S, Talavera-Rodríguez A, Gosalbes MJ, Madrid N, Pérez-Molina JA, Elliott RJ, Navia B, Lanza VF, Vallejo A, Osman M, Dronda F, Budree S, Zamora J, Gutiérrez C, Manzano M, Vivancos MJ, Ron R, Martínez-Sanz J, Herrera S, Ansa U, Moya A, Moreno S. Fecal microbiota transplantation in HIV: A pilot placebo-controlled study. Nat Commun 2021; 12:1139. [PMID: 33602945 PMCID: PMC7892558 DOI: 10.1038/s41467-021-21472-1] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 01/29/2021] [Indexed: 02/07/2023] Open
Abstract
Changes in the microbiota have been linked to persistent inflammation during treated HIV infection. In this pilot double-blind study, we study 30 HIV-infected subjects on antiretroviral therapy (ART) with a CD4/CD8 ratio < 1 randomized to either weekly fecal microbiota capsules or placebo for 8 weeks. Stool donors were rationally selected based on their microbiota signatures. We report that fecal microbiota transplantation (FMT) is safe, not related to severe adverse events, and attenuates HIV-associated dysbiosis. FMT elicits changes in gut microbiota structure, including significant increases in alpha diversity, and a mild and transient engraftment of donor's microbiota during the treatment period. The greater engraftment seems to be achieved by recent antibiotic use before FMT. The Lachnospiraceae and Ruminococcaceae families, which are typically depleted in people with HIV, are the taxa more robustly engrafted across time-points. In exploratory analyses, we describe a significant amelioration in the FMT group in intestinal fatty acid-binding protein (IFABP), a biomarker of intestinal damage that independently predicts mortality. Gut microbiota manipulation using a non-invasive and safe strategy of FMT delivery is feasible and deserves further investigation. Trial number: NCT03008941.
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Affiliation(s)
- Sergio Serrano-Villar
- Department of Infectious Diseases, Hospital Universitario Ramon y Cajal, and IRYCIS, Madrid, Spain.
| | | | - María José Gosalbes
- Area of Genomics and Health, FISABIO-Salud Pública, Valencia, Spain
- Centro de Investigación Biomédica en Red Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
| | - Nadia Madrid
- Department of Infectious Diseases, Hospital Universitario Ramon y Cajal, and IRYCIS, Madrid, Spain
| | - José A Pérez-Molina
- Department of Infectious Diseases, Hospital Universitario Ramon y Cajal, and IRYCIS, Madrid, Spain
| | | | - Beatriz Navia
- Department of Nutrition, Facultad de Farmacia, Universidad Complutense, Madrid, Spain
| | - Val F Lanza
- Bioinformatics Unit, Hospital Universitario Ramon y Cajal, IRYCIS, Madrid, Spain
| | - Alejandro Vallejo
- Department of Infectious Diseases, Hospital Universitario Ramon y Cajal, and IRYCIS, Madrid, Spain
| | | | - Fernando Dronda
- Department of Infectious Diseases, Hospital Universitario Ramon y Cajal, and IRYCIS, Madrid, Spain
| | | | - Javier Zamora
- Barts and the London School for Medicine and Dentistry. Queen Mary University of London, London, UK
| | - Carolina Gutiérrez
- Department of Infectious Diseases, Hospital Universitario Ramon y Cajal, and IRYCIS, Madrid, Spain
| | - Mónica Manzano
- Department of Nutrition, Facultad de Farmacia, Universidad Complutense, Madrid, Spain
| | - María Jesús Vivancos
- Department of Infectious Diseases, Hospital Universitario Ramon y Cajal, and IRYCIS, Madrid, Spain
| | - Raquel Ron
- Department of Infectious Diseases, Hospital Universitario Ramon y Cajal, and IRYCIS, Madrid, Spain
| | - Javier Martínez-Sanz
- Department of Infectious Diseases, Hospital Universitario Ramon y Cajal, and IRYCIS, Madrid, Spain
| | - Sabina Herrera
- Department of Infectious Diseases, Hospital Universitario Ramon y Cajal, and IRYCIS, Madrid, Spain
| | - Uxua Ansa
- Department of Infectious Diseases, Hospital Universitario Ramon y Cajal, and IRYCIS, Madrid, Spain
| | - Andrés Moya
- Area of Genomics and Health, FISABIO-Salud Pública, Valencia, Spain
- Institute for Integrative Systems Biology (I2SysBio), The University of Valencia and The Spanish National Research Council (CSIC)-UVEG), Valencia, Spain
| | - Santiago Moreno
- Department of Infectious Diseases, Hospital Universitario Ramon y Cajal, and IRYCIS, Madrid, Spain
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Allegretti JR, Elliott RJ, Ladha A, Njenga M, Warren K, O’Brien K, Budree S, Osman M, Fischer M, Kelly CR, Kassam Z. Stool processing speed and storage duration do not impact the clinical effectiveness of fecal microbiota transplantation. Gut Microbes 2020; 11:1806-1808. [PMID: 32552337 PMCID: PMC7524162 DOI: 10.1080/19490976.2020.1768777] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Affiliation(s)
- Jessica R. Allegretti
- Division of Gastroenterology, Brigham and Women’s Hospital, Boston, MA, USA,CONTACT Jessica R. Allegretti Division of Gastroenterology, Brigham and Women’s Hospital, Boston, MA02115
| | | | - Alim Ladha
- OpenBiome, Cambridge, MA, USA,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | | | | | | | - Shrish Budree
- OpenBiome, Cambridge, MA, USA,Finch Therapeutics, Somerville, MA, USA
| | | | - Monika Fischer
- Division of Gastroenterology, Indiana University, Indianapolis, IN, USA
| | - Colleen R. Kelly
- Department of Medicine, Warren Alpert Medical School of Brown University, Providence, RI, USA
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Zanoni BC, Elliott RJ, Neilan AM, Haberer JE. Screening for HIV and linkage to care in adolescents: insights from a systematic review of recent interventions in high- versus low- and middle-income settings. Adolesc Health Med Ther 2018; 9:211-235. [PMID: 30584383 PMCID: PMC6287534 DOI: 10.2147/ahmt.s153204] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Introduction Compared to adults, adolescents and young adults have a higher incidence of HIV infection, yet lower rates of HIV testing. Few evidence-based interventions effectively diagnose new HIV infections among adolescents while successfully providing linkage to care. Methods We conducted a systematic review of recent interventions to increase HIV testing among adolescents and young adults using data retrieved from PubMed and Google Scholar, and using abstracts presented at the International AIDS Society conferences and Conference on Retroviruses and Opportunistic Infections published between January 1, 2015, and April 28, 2018. Results We identified 36 interventions (N=14 in high- income countries and N=22 in low- and middle-income countries) that were published in the literature (N=28) or presented at conferences (N=8). Interventions were categorized as behavioral/educational, alternate venue/self-testing, youth-friendly services, technology/mobile health, incentives, or peer-based/community-based interventions. The studies consisted of randomized controlled trials (RCTs), prospective and retrospective observational studies, and quasi-experimental/pre-post evaluations with variable sample sizes. Study designs, populations, and settings varied. All categories showed some degree of acceptability, yet not all interventions were effective in increasing HIV testing. Effectiveness was seen in more than one RCT involving technology/mobile health (2/3 RCTs) and alternative venue/self-testing (3/3 RCTs) interventions, and only in one RCT each for behavioral interventions, community interventions, and incentives. There were no effective RCTs for adolescent-friendly services. Data were limited on the number of new infections identified and on the methods to increase linkage to care after diagnosis. Conclusion Future studies should include combinations of proven methods for engaging adolescents in HIV testing, while ensuring effective methods of linkage to care.
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Affiliation(s)
- Brian C Zanoni
- Department of Global Health, Massachusetts General Hospital, Boston, MA, USA, .,Department of Medicine, Harvard Medical School, Boston, MA, USA,
| | - Ryan J Elliott
- Premedical Program, Harvard Extension School, Cambridge, MA, USA
| | - Anne M Neilan
- Department of Global Health, Massachusetts General Hospital, Boston, MA, USA, .,Department of Medicine, Harvard Medical School, Boston, MA, USA,
| | - Jessica E Haberer
- Department of Global Health, Massachusetts General Hospital, Boston, MA, USA, .,Department of Medicine, Harvard Medical School, Boston, MA, USA,
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Trojetto T, Elliott RJ, Rashid S, Wong S, Dlugosz K, Helm D, Wickerson L, Brooks D. Availability, characteristics, and barriers of rehabilitation programs in organ transplant populations across Canada. Clin Transplant 2011. [PMID: 21955056 DOI: 10.1111/j.1399-0012.2011.10501.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Rehabilitation is receiving increasingly more attention from the medical community in the management of individuals' pre- and post-organ transplantation. A cross-sectional descriptive survey was administered to all known transplant programs across Canada to explore the availability, characteristics, and barriers of rehabilitation programs pre- and post-heart, lung, kidney, and liver transplantation. Of the 58 programs surveyed, 35 agreed to participate (nine heart, six lung, 13 kidney, seven liver), and six refused for a response rate of 71%. Twelve transplant programs that offered rehabilitation were identified (six heart, five lung, one liver). All rehabilitation programs identified included aerobic exercises, strength training, and education and involved a multidisciplinary team. The Six Minute Walk Test and the Medical Outcomes Short Form-36 questionnaire were the most commonly used outcome measures. In kidney and liver transplant programs, over 50% of respondents from these programs cited lack of funding, shortage of health care personnel, and a low volume of patients in a centralized region as barriers to providing rehabilitation programs. Rehabilitation can play an integral role in pre- and post-transplantation management, and barriers to access and provision of rehabilitation for organ transplant populations should be examined further.
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Affiliation(s)
- T Trojetto
- Department of Physical Therapy, University of Toronto, Toronto, ON, Canada
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Trojetto T, Elliott RJ, Rashid S, Wong S, Dlugosz K, Helm D, Wickerson L, Brooks D. Availability, characteristics, and barriers of rehabilitation programs in organ transplant populations across Canada. Clin Transplant 2011; 25:E571-8. [PMID: 21955056 DOI: 10.1111/j.1399-0012.2011.01501.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Rehabilitation is receiving increasingly more attention from the medical community in the management of individuals' pre- and post-organ transplantation. A cross-sectional descriptive survey was administered to all known transplant programs across Canada to explore the availability, characteristics, and barriers of rehabilitation programs pre- and post-heart, lung, kidney, and liver transplantation. Of the 58 programs surveyed, 35 agreed to participate (nine heart, six lung, 13 kidney, seven liver), and six refused for a response rate of 71%. Twelve transplant programs that offered rehabilitation were identified (six heart, five lung, one liver). All rehabilitation programs identified included aerobic exercises, strength training, and education and involved a multidisciplinary team. The Six Minute Walk Test and the Medical Outcomes Short Form-36 questionnaire were the most commonly used outcome measures. In kidney and liver transplant programs, over 50% of respondents from these programs cited lack of funding, shortage of health care personnel, and a low volume of patients in a centralized region as barriers to providing rehabilitation programs. Rehabilitation can play an integral role in pre- and post-transplantation management, and barriers to access and provision of rehabilitation for organ transplant populations should be examined further.
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Affiliation(s)
- T Trojetto
- Department of Physical Therapy, University of Toronto, Toronto, ON, Canada
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Elliott RJ, Stevens KWH. A Preliminary Survey of the Paramagnetic Resonance Phenomena observed in Rare Earth Ethyl Sulphates. ACTA ACUST UNITED AC 2002. [DOI: 10.1088/0370-1298/64/2/115] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Elliott RJ, Taylor DW. Theory of correlations and scattering of lattice vibrations by defects using double-time Green's functions. ACTA ACUST UNITED AC 2002. [DOI: 10.1088/0370-1328/83/2/302] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Elliott RJ, Parkinson JB. Theory of spin-phonon coupling in concentrated paramagnetic salts and its effect on thermal conductivity. ACTA ACUST UNITED AC 2002. [DOI: 10.1088/0370-1328/92/4/325] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Elliott RJ, Gehring GA, Malozemoff AP, Smith SRP, Staude WS, Tyte RN. Theory of co-operative Jahn-Teller distortions in DyVO4and TbVO4(Phase transitions). ACTA ACUST UNITED AC 2001. [DOI: 10.1088/0022-3719/4/9/013] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Sandercock JR, Palmer SB, Elliott RJ, Hayes W, Smith SRP, Young AP. Brillouin scattering, ultrasonic and theoretical studies of acoustic anomalies in crystals showing Jahn-Teller phase transitions. ACTA ACUST UNITED AC 2001. [DOI: 10.1088/0022-3719/5/21/017] [Citation(s) in RCA: 119] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Buchanan M, Buyers WJL, Elliott RJ, Harley RT, Hayes W, Perry AM, Saville ID. Two-magnon raman scattering and infrared absorption in (MnZn)F2. ACTA ACUST UNITED AC 2001. [DOI: 10.1088/0022-3719/5/15/016] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Buyers WJL, Pepper DE, Elliott RJ. Theory of spin waves in disordered antiferromagnets. I. Application to (Mn, Co)F2and K(Mn, Co)F3. ACTA ACUST UNITED AC 2001. [DOI: 10.1088/0022-3719/5/18/011] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Harris AB, Leath PL, Nickel BG, Elliott RJ. Excitations in the dilute Heisenberg ferromagnet using the coherent potential approximation. ACTA ACUST UNITED AC 2001. [DOI: 10.1088/0022-3719/7/9/010] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Harley RT, Hayes W, Perry AM, Smith SRP, Elliott RJ, Saville ID. Cooperative Jahn-Teller effects in the mixed crystals TbpGd1-pVO4and DypY1-pVO4. ACTA ACUST UNITED AC 2001. [DOI: 10.1088/0022-3719/7/17/022] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Tahir-Kheli RA, Fujiwara T, Elliott RJ. CPA theory of diluted Heisenberg ferromagnet with random first- and second-neighbour exchange bonds. ACTA ACUST UNITED AC 2001. [DOI: 10.1088/0022-3719/11/3/012] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Elliott RJ, Bennet AJ, Braun CA, MacLeod AM, Borgford TJ. Active-site variants of Streptomyces griseus protease B with peptide-ligation activity. Chem Biol 2000; 7:163-71. [PMID: 10712933 DOI: 10.1016/s1074-5521(00)00086-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND Peptide-ligating technologies facilitate a range of manipulations for the study of protein structure and function that are not possible using conventional genetic or mutagenic methods. To different extents, the currently available enzymatic and nonenzymatic methodologies are synthetically demanding, sequence-dependent and/or sensitive to denaturants. No single coupling method is universally applicable. Accordingly, new strategies for peptide ligation are sought. RESULTS Site-specific variants (Ser195-->Gly, S195G, and Ser195-->Ala, S195A) of Streptomyces griseus protease B (SGPB) were generated that efficiently catalyze peptide ligation (i.e., aminolysis of ester-, thioester- and para-nitroanilide-activated peptides). The variants also showed reduced hydrolytic activity relative to the wild-type enzyme. The ratio of aminolysis to hydrolysis was greater for the S195A variant, which was also capable of catalyzing ligation in concentrations of urea as high as 2 M. CONCLUSIONS Mutagenic substitution of the active-site serine residue of SGPB by either glycine or alanine has created a unique class of peptide-ligating catalysts that are useful for coupling relatively stable ester- and para-nitroanilide-activated substrates. Ligation proceeds through an acyl-enzyme intermediate involving His57. Serine to alanine mutations may provide a general strategy for converting proteases with chymotrypsin-like protein folds into peptide-coupling enzymes.
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Affiliation(s)
- R J Elliott
- Institute of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, V5A 1S6, Canada
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McCleave MJ, Black JM, Elliott RJ. Visualisation of hippuricase activity on native polyacrylamide gels. Biochem Soc Trans 1997; 25:143S. [PMID: 9057041 DOI: 10.1042/bst025143s] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- M J McCleave
- School of Biology and Biochemistry, Queen's University of Belfast, N. Ireland
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Schwabe NF, Elliott RJ, Wingreen NS. Ruderman-Kittel-Kasuya-Yosida interaction across a tunneling junction out of equilibrium. Phys Rev B Condens Matter 1996; 54:12953-12968. [PMID: 9985154 DOI: 10.1103/physrevb.54.12953] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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