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Nemzow L, Boehringer T, Bacon B, Turner HC. Development of a human peripheral blood ex vivo model for rapid protein biomarker detection and applications to radiation biodosimetry. PLoS One 2023; 18:e0289634. [PMID: 37561730 PMCID: PMC10414586 DOI: 10.1371/journal.pone.0289634] [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] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 07/21/2023] [Indexed: 08/12/2023] Open
Abstract
In the event of a widespread radiological incident, thousands of people may be exposed to a wide range of ionizing radiation. In this unfortunate scenario, there will be a need to quickly screen a large number of people to assess the amount of radiation exposure and triage for medical treatment. In our earlier work, we previously identified and validated a panel of radiosensitive protein biomarkers in blood leukocytes, using the humanized-mouse and non-human primate (NHP) models. The objective of this work was to develop a high-throughput imaging flow-cytometry (IFC) based assay for the rapid measurement of protein biomarker expression in human peripheral blood samples irradiated ex vivo. In this assay design, peripheral human blood samples from healthy adult donors were exposed to 0-5 Gy X-irradiation ex vivo and cultured for up to 2 days. Samples were stained with a cocktail of surface antigens (CD66b, CD20, and CD3), fixed and permeabilized, and intracellularly stained for BAX (Bcl-2-associated X) protein, used here as a representative biomarker. Samples were interrogated by IFC, and a uniform analysis template was created to measure biomarker expression in heterogeneous and specific leukocyte subtype populations at each time point. In this human blood ex vivo model, we show that within gated populations of leukocyte subtypes, B-cells are highly radiosensitive with the smallest surviving fraction, followed by T-cells and granulocytes. Dose-dependent biomarker responses were measured in the lymphocytes, B-, and T-cell populations, but not in the granulocytes, with dose-response curves showing increasing fold changes in BAX protein expression up to Day 2 in lymphocyte populations. We present here the successful use of this ex vivo model for the development of radiation dose-response curves of a candidate protein biomarker towards future applications of dose reconstruction and biodosimetry.
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Affiliation(s)
- Leah Nemzow
- Center for Radiological Research, Columbia University Irving Medical Center, New York, New York, United States of America
| | - Thomas Boehringer
- Center for Radiological Research, Columbia University Irving Medical Center, New York, New York, United States of America
| | - Bezalel Bacon
- Center for Radiological Research, Columbia University Irving Medical Center, New York, New York, United States of America
| | - Helen C. Turner
- Center for Radiological Research, Columbia University Irving Medical Center, New York, New York, United States of America
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Bacon B, Repin M, Shuryak I, Wu HC, Santella RM, Terry MB, Brenner DJ, Turner HC. High-throughput measurement of double strand break global repair phenotype in peripheral blood mononuclear cells after long-term cryopreservation. Cytometry A 2023; 103:575-583. [PMID: 36823754 PMCID: PMC10680149 DOI: 10.1002/cyto.a.24725] [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] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 01/02/2023] [Accepted: 02/21/2023] [Indexed: 02/25/2023]
Abstract
Peripheral blood mononuclear cells (PBMCs) are a useful model for biochemical assays, particularly for etiological studies. We describe here a method for measuring DNA repair capacity (DRC) in archival cryogenically preserved PBMCs. To model DRC, we measured γ-H2AX repair kinetics in thawed PBMCs after irradiation with 3 Gy gamma rays. Time-dependent fluorescently labeled γ-H2AX levels were measured at five time points from 1 to 20 h, yielding an estimate of global DRC repair kinetics as well as a measure of unrepaired double strand breaks at 20 h. While γ-H2AX levels are traditionally measured by either microscopy or flow-cytometry, we developed a protocol for imaging flow cytometry (IFC) that combines the detailed information of microscopy with the statistical power of flow methods. The visual imaging component of the IFC allows for monitoring aspects such as cellular health and apoptosis as well as fluorescence localization of the γ-H2AX signal, which ensures the power and significance of this technique. Application of a machine-learning based image classification improved flow cytometry fluorescent measurements by identifying apoptotic cells unable to undergo DNA repair. We present here DRC repair parameters from 18 frozen archival PBMCs and 28 fresh blood samples collected from a demographically diverse cohort of women measured in a high-throughput IFC format. This thaw method and assay can be used alone or in conjunction with other assays to measure etiological phenotypes in cryogenic biobanks of PBMCs.
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Affiliation(s)
- Bezalel Bacon
- Center for Radiological Research, Columbia University Irving Medical Center, New York, (NY)
| | - Mikhail Repin
- Center for Radiological Research, Columbia University Irving Medical Center, New York, (NY)
| | - Igor Shuryak
- Center for Radiological Research, Columbia University Irving Medical Center, New York, (NY)
| | - Hui-Chen Wu
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York
- Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center
| | - Regina M. Santella
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York
- Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center
| | - Mary Beth Terry
- Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center
- Department of Epidemiology, Mailman School of Public Health, Columbia University, Irving Medical Center, New York
| | - David J. Brenner
- Center for Radiological Research, Columbia University Irving Medical Center, New York, (NY)
| | - Helen C. Turner
- Center for Radiological Research, Columbia University Irving Medical Center, New York, (NY)
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Nisbett LM, Binnenkade L, Bacon B, Hossain S, Kotloski NJ, Brutinel ED, Hartmann R, Drescher K, Arora DP, Muralidharan S, Thormann KM, Gralnick JA, Boon EM. NosP Signaling Modulates the NO/H-NOX-Mediated Multicomponent c-Di-GMP Network and Biofilm Formation in Shewanella oneidensis. Biochemistry 2019; 58:4827-4841. [PMID: 31682418 PMCID: PMC7290162 DOI: 10.1021/acs.biochem.9b00706] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Biofilms form when bacteria aggregate in a self-secreted exopolysaccharide matrix; they are resistant to antibiotics and implicated in disease. Nitric oxide (NO) is known to mediate biofilm formation in many bacteria via ligation to H-NOX (heme-NO/oxygen binding) domains. Most NO-responsive bacteria, however, lack H-NOX domain-containing proteins. We have identified another NO-sensing protein (NosP), which is predicted to be involved in two-component signaling and biofilm regulation in many species. Here, we demonstrate that NosP participates in the previously described H-NOX/NO-responsive multicomponent c-di-GMP signaling network in Shewanella oneidensis. Strains lacking either nosP or its co-cistronic kinase nahK (previously hnoS) produce immature biofilms, while hnoX and hnoK (kinase responsive to NO/H-NOX) mutants result in wild-type biofilm architecture. We demonstrate that NosP regulates the autophosphorylation activity of NahK as well as HnoK. HnoK and NahK have been shown to regulate three response regulators (HnoB, HnoC, and HnoD) that together comprise a NO-responsive multicomponent c-di-GMP signaling network. Here, we propose that NosP/NahK adds regulation on top of H-NOX/HnoK to modulate this c-di-GMP signaling network, and ultimately biofilm formation, by governing the flux of phosphate through both HnoK and NahK. In addition, it appears that NosP and H-NOX act to counter each other in a push-pull mechanism; NosP/NahK promotes biofilm formation through inhibition of H-NOX/HnoK signaling, which itself reduces the extent of biofilm formation. Addition of NO results in a reduction of c-di-GMP and biofilm formation, primarily through disinhibition of HnoK activity.
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Affiliation(s)
- Lisa-Marie Nisbett
- Graduate Program in Biochemistry and Structural Biology, Stony Brook University, Stony Brook, New York 11794-3400, United States
| | - Lucas Binnenkade
- Institute for Microbiology and Molecular Biology, Justus-Liebig-Universität Giessen, D-35392 Giessen, Germany
| | - Bezalel Bacon
- Graduate Program in Biochemistry and Structural Biology, Stony Brook University, Stony Brook, New York 11794-3400, United States
| | - Sajjad Hossain
- Department of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, United States
| | - Nicholas J. Kotloski
- Department of Plant and Microbial Biology, University of Minnesota—Twin Cities, St. Paul, Minnesota 55108, United States
| | - Evan D. Brutinel
- Department of Plant and Microbial Biology, University of Minnesota—Twin Cities, St. Paul, Minnesota 55108, United States
| | - Raimo Hartmann
- Max Planck Institute for Terrestrial Microbiology, Karl-von-Frisch-Strasse 10, 35043 Marburg, Germany
| | - Knut Drescher
- Max Planck Institute for Terrestrial Microbiology, Karl-von-Frisch-Strasse 10, 35043 Marburg, Germany
- Department of Physics, Philipps-Universität Marburg, Renthof 6, 35032 Marburg, Germany
| | - Dhruv P. Arora
- Department of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, United States
| | - Sandhya Muralidharan
- Department of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, United States
| | - Kai M. Thormann
- Institute for Microbiology and Molecular Biology, Justus-Liebig-Universität Giessen, D-35392 Giessen, Germany
| | - Jeffrey A. Gralnick
- Department of Plant and Microbial Biology, University of Minnesota—Twin Cities, St. Paul, Minnesota 55108, United States
| | - Elizabeth M. Boon
- Graduate Program in Biochemistry and Structural Biology, Stony Brook University, Stony Brook, New York 11794-3400, United States
- Department of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, United States
- Institute of Chemical Biology & Drug Discovery, Stony Brook University, Stony Brook, New York 11794-3400, United States
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Abstract
SIGNIFICANCE The molecule nitric oxide (NO) has been shown to regulate behaviors in bacteria, including biofilm formation. NO detection and signaling in bacteria is typically mediated by hemoproteins such as the bis-(3',5')-cyclic dimeric adenosine monophosphate-specific phosphodiesterase YybT, the transcriptional regulator dissimilative nitrate respiration regulator, or heme-NO/oxygen binding (H-NOX) domains. H-NOX domains are well-characterized primary NO sensors that are capable of detecting nanomolar NO and influencing downstream signal transduction in many bacterial species. However, many bacteria, including the human pathogen Pseudomonas aeruginosa, respond to nanomolar concentrations of NO but do not contain an annotated H-NOX domain, indicating the existence of an additional nanomolar NO-sensing protein (NosP). Recent Advances: A newly discovered bacterial hemoprotein called NosP may also act as a primary NO sensor in bacteria, in addition to, or in place of, H-NOX. NosP was first described as a regulator of a histidine kinase signal transduction pathway that is involved in biofilm formation in P. aeruginosa. CRITICAL ISSUES The molecular details of NO signaling in bacteria are still poorly understood. There are still many bacteria that are NO responsive but do encode either H-NOX or NosP domains in their genomes. Even among bacteria that encode H-NOX or NosP, many questions remain. FUTURE DIRECTIONS The molecular mechanisms of NO regulation in many bacteria remain to be established. Future studies are required to gain knowledge about the mechanism of NosP signaling. Advancements on structural and molecular understanding of heme-based sensors in bacteria could lead to strategies to alleviate or control bacterial biofilm formation or persistent biofilm-related infections.
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Affiliation(s)
| | - Lisa-Marie Nisbett
- 2 Graduate Program in Biochemistry and Structural Biology, Stony Brook University , Stony Brook, New York
| | - Bezalel Bacon
- 2 Graduate Program in Biochemistry and Structural Biology, Stony Brook University , Stony Brook, New York
| | - Elizabeth Boon
- 1 Department of Chemistry, Stony Brook University , Stony Brook, New York.,2 Graduate Program in Biochemistry and Structural Biology, Stony Brook University , Stony Brook, New York.,3 Institute of Chemical Biology and Drug Design, Stony Brook University , Stony Brook, New York
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Flamm SL, Bacon B, Curry MP, Milligan S, Nwankwo CU, Tsai N, Younossi Z, Afdhal N. Real-world use of elbasvir-grazoprevir in patients with chronic hepatitis C: retrospective analyses from the TRIO network. Aliment Pharmacol Ther 2018; 47:1511-1522. [PMID: 29665097 DOI: 10.1111/apt.14635] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 10/23/2017] [Accepted: 03/06/2018] [Indexed: 12/12/2022]
Abstract
BACKGROUND Elbasvir-grazoprevir is indicated for chronic hepatitis C virus (HCV) genotypes 1 and 4. AIM To evaluate the utilization and outcomes of chronic HCV patients treated with elbasvir-grazoprevir in the United States. METHODS We conducted a retrospective cohort study of adults treated with elbasvir-grazoprevir with or without ribavirin for chronic HCV genotypes 1 or 4 infection. Data were collected from healthcare providers and specialty pharmacies through Innervation Platform, a proprietary, cloud-based disease management program from Trio Health. The primary endpoint was per protocol sustained virological response 12 weeks post-treatment (SVR12). RESULTS Among 470 patients treated in 2016, 95% had HCV genotype 1 infection, 80% (373/468) were HCV treatment naïve and 70% (327/468) had non-cirrhotic disease. Almost 3 quarters (73%) of patients received care in community practices. The majority (89%) of patients received elbasvir-grazoprevir for 12 weeks. Per protocol SVR12 rates were 99% (396/402) for HCV genotype 1 and 95% (21/22) for HCV genotype 4. Among patients with Stage 4 or 5 chronic kidney diseases, 99% (113/114) achieved SVR12. In univariate analyses, variables significantly associated with per protocol SVR12 for the entire sample were therapy duration (P = 0.001), treatment experience (P = 0.016), and cirrhosis status (P = 0.001). However, among HCV genotype 1 patients, no variables were significant. Intent-to-treat SVR12 rates were 89% (396/447) for HCV genotype 1 and 91% (21/23) for HCV genotype 4. CONCLUSION Elbasvir-grazoprevir is highly effective, and in this 2016 cohort, its use was predominantly in patients with HCV genotype 1 and as a 12-week therapy without ribavirin.
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Affiliation(s)
- S L Flamm
- Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - B Bacon
- Saint Louis University School of Medicine, St. Louis, MO, USA
| | - M P Curry
- Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - S Milligan
- Trio Health Analytics, La Jolla, CA, USA
| | | | - N Tsai
- Queens Medical Center, University of Hawaii, Honolulu, HI, USA
| | - Z Younossi
- Department of Medicine, Center for Liver Diseases, Inova Fairfax Hospital, Falls Church, VA, USA
| | - N Afdhal
- Beth Israel Deaconess Medical Center, Boston, MA, USA
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Boudes PF, Bacon B, Varga M, Choi Y, Steinberg A, Turner T, Swain M. A202 BIOCHEMICAL PROFILE IN 68 PRIMARY BILIARY CHOLANGITIS (PBC) SUBJECTS HAVING AN INADEQUATE RESPONSE TO URSODEOXYCHOLIC ACID. J Can Assoc Gastroenterol 2018. [DOI: 10.1093/jcag/gwy008.203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
| | - B Bacon
- Saint Louis University School of Medicine, St Louis, MO
| | - M Varga
- CymaBay Therapeutics, Newark, CA
| | - Y Choi
- CymaBay Therapeutics, Newark, CA
| | | | - T Turner
- Medpace Reference Laboratories, Cincinnati, OH
| | - M Swain
- Univ Calgary, Calgary, AB, Canada
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Curry MP, Tapper EB, Bacon B, Dieterich D, Flamm SL, Guest L, Kowdley KV, Lee Y, Milligan S, Tsai N, Younossi Z, Afdhal NH. Effectiveness of 8- or 12-weeks of ledipasvir and sofosbuvir in real-world treatment-naïve, genotype 1 hepatitis C infected patients. Aliment Pharmacol Ther 2017; 46:540-548. [PMID: 28691377 DOI: 10.1111/apt.14204] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Revised: 11/18/2016] [Accepted: 06/04/2017] [Indexed: 12/13/2022]
Abstract
BACKGROUND Treatment of genotype 1 hepatitis C virus (HCV) infection with combination direct acting anti-virals is associated with very high rates of sustained virological response (SVR). Daily combination of ledipasvir and sofosbuvir for 12 weeks is approved for the treatment of genotype 1 HCV patients, though noncirrhotic patients who are naïve to treatment with a baseline HCV RNA <6 million IU/mL can be treated for 8 weeks. This guidance stemmed from a post hoc analysis of the ION 3 clinical trial, which demonstrated similar SVR for patients treated with ledipasvir and sofosbuvir with or without ribavirin for 8 or 12 weeks. AIM To compare the SVR for 8 weeks vs 12 weeks of ledipasvir and sofosbuvir in HCV infected patients in a real-world setting. METHODS We performed an observational real-world cohort study of treatment success following 8 or 12 weeks of ledipasvir and sofosbuvir for treatment-naïve genotype 1 HCV patients. RESULTS A total of 826 patients were treated for either 8 (n=252) or 12 weeks (n=574) with ledipasvir and sofosbuvir and achieved SVR rate of 95.3% and there was no statistical difference in SVR rates in the two groups irrespective of any clinical or virological variables. CONCLUSIONS In treatment-naïve HCV genotype 1 patients, SVR was 95% in those treated for either 8 weeks or 12 weeks with ledipasvir and sofosbuvir. 8 week ledipasvir and sofosbuvir can reduce costs without compromising outcomes for those patients who qualify for such regimen.
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Affiliation(s)
- M P Curry
- Division of Gastroenterology and Hepatology, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - E B Tapper
- Division of Gastroenterology and Hepatology, University of Michigan, Ann Arbor, MI, USA
| | - B Bacon
- Division of Gastroenterology/ Hepatology, Saint Louis University School of Medicine, Saint Louis, MO, USA
| | - D Dieterich
- Division of Liver Diseases, Department of Medicine, Mount Sinai School of Medicine, New York, NY, USA
| | - S L Flamm
- Division of Hepatology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - L Guest
- Trio Health Analytics, La Jolla, CA, USA
| | - K V Kowdley
- Liver Care Network, Swedish Medical Center, Seattle, WA, USA
| | - Y Lee
- Trio Health Analytics, La Jolla, CA, USA
| | - S Milligan
- Trio Health Analytics, La Jolla, CA, USA
| | - N Tsai
- The Liver Center, Queen's Medical Center, Honolulu, HI, USA
| | - Z Younossi
- Center for Liver Diseases, Department of Medicine, Inova Fairfax Hospital, Falls Church, VA, USA
| | - N H Afdhal
- Division of Gastroenterology and Hepatology, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
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Abstract
Low concentrations of nitric oxide (NO) modulate varied behaviours in bacteria including biofilm dispersal and quorum sensing-dependent light production. H-NOX (haem-nitric oxide/oxygen binding) is a haem-bound protein domain that has been shown to be involved in mediating these bacterial responses to NO in several organisms. However, many bacteria that respond to nanomolar concentrations of NO do not contain an annotated H-NOX domain. Nitric oxide sensing protein (NosP), a newly discovered bacterial NO-sensing haemoprotein, may fill this role. The focus of this review is to discuss structure, ligand binding, and activation of H-NOX proteins, as well as to discuss the early evidence for NO sensing and regulation by NosP domains. Further, these findings are connected to the regulation of bacterial biofilm phenotypes and symbiotic relationships.
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Affiliation(s)
- Bezalel Bacon
- Stony Brook University, Stony Brook, NY, United States
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Howard B, van Herck H, Guillen J, Bacon B, Joffe R, Ritskes-Hoitinga M. Report of the FELASA Working Group on evaluation of quality systems for animal units. Lab Anim 2016; 38:103-18. [PMID: 15070450 DOI: 10.1258/002367704322968786] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [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: 11/18/2022]
Abstract
This report compares and considers the merits of existing, internationally available quality management systems suitable for implementation in experimental animal facilities. These are: the Good Laboratory Practice Guidelines, ISO 9000:2000 (International Organization for Standardization) and AAALAC International (Association for Assessment and Accreditation of Laboratory Animal Care International). Good laboratory practice (GLP) is a legal requirement for institutions undertaking non-clinical health and environmental studies for the purpose of registering or licensing for use and which have to be 'GLP-compliant'. GLP guidelines are often only relevant for and obtainable by those institutions. ISO is primarily an external business standard, which provides a management tool to master and optimize a business activity; it aims to implement and enhance 'customer satisfaction'. AAALAC is primarily a peer-reviewed system of accreditation which evaluates the organization and procedures in programmes of animal care and use to ensure the appropriate use of animals, safeguard animal well-being (ensuring state-of-the-art housing, management, procedural techniques, etc.) as well as the management of health and safety of staff. Management needs to determine, on the basis of a facility's specific goals, whether benefits would arise from the introduction of a quality system and, if so, which system is most appropriate. The successful introduction of a quality system confers peer-recognition against an independent standard, thereby providing assurance of standards of animal care and use, improving the quality of animal studies, and contributing to the three Rs—reduction, refinement and replacement.
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Affiliation(s)
- B Howard
- University of Sheffield, Western Bank, Sheffield S10 2TN, UK
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Nisbett L, Bacon B, Boon E. Characterization of a NosP signal transduction pathway in
Shewanella oneidensis. FASEB J 2015. [DOI: 10.1096/fasebj.29.1_supplement.896.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Lisa‐Marie Nisbett
- Biochemistry and Structural Biology Stony Brook UniversityStony BrookNew YorkUnited States
| | - Bezalel Bacon
- Biochemistry and Structural Biology Stony Brook UniversityStony BrookNew YorkUnited States
| | - Elizabeth Boon
- Biochemistry and Structural Biology Stony Brook UniversityStony BrookNew YorkUnited States
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Manns MP, Pockros PJ, Norkrans G, Smith CI, Morgan TR, Häussinger D, Shiffman ML, Hadziyannis SJ, Schmidt WN, Jacobson IM, Bárcena R, Schiff ER, Shaikh OS, Bacon B, Marcellin P, Deng W, Esteban-Mur R, Poynard T, Pedicone LD, Brass CA, Albrecht JK, Gordon SC. Long-term clearance of hepatitis C virus following interferon α-2b or peginterferon α-2b, alone or in combination with ribavirin. J Viral Hepat 2013; 20:524-9. [PMID: 23808990 DOI: 10.1111/jvh.12074] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [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] [Received: 06/13/2012] [Accepted: 12/18/2012] [Indexed: 12/13/2022]
Abstract
Sustained virologic response (SVR) is the standard measure for evaluating response to therapy in patients with chronic hepatitis C (CHC). The aim of this study was to prospectively assess the durability of SVR in the pivotal studies of peginterferon (PEG-IFN) α-2b or IFN α-2b. We conducted two phase 3b long-term follow-up studies of patients previously treated for CHC in eight prospective randomized studies of IFN α-2b and/or PEG-IFN α-2b. Patients who achieved SVR [undetectable hepatitis C virus (HCV) RNA 24 weeks after completion of treatment] were eligible for inclusion in these follow-up studies. In total, 636 patients with SVR following treatment with IFN α-2b and 366 with SVR following treatment with PEG-IFN α-2b were enrolled. Definite relapse (quantifiable serum HCV RNA with no subsequent undetectable HCV RNA) was reported in six patients treated with IFN α-2b and three patients treated with PEG-IFN α-2b. Based on these relapses, the point estimate for the likelihood of maintaining response after 5 years was 99.2% [95% confidence interval (CI), 98.1-99.7%] for IFN α-2b and 99.4% (95% CI, 97.7-99.9%) for PEG-IFN α-2b. Successful treatment of hepatitis C with PEG-IFN α-2b or IFN α-2b leads to clinical cure of hepatitis C in the vast majority of cases.
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Affiliation(s)
- M P Manns
- Department of Gastroenterology, Hepatology and Endocrinology, Hannover Medical School, Hannover, Germany.
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Zeuzem S, Pappas S, Nyberg L, Greenbloom S, Gibas A, Bacon B, Godofsky E, Harley H, Bronowicki J, Lin A, Hooper G, Shiffman M. P.285 Differences in virus and host characteristics between patients with HCV genotype 2 or 3 participating in a large international study. J Clin Virol 2006. [DOI: 10.1016/s1386-6532(06)80465-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Cheng PN, Marcellin P, Bacon B, Farrell G, Parsons I, Wee T, Chang TT. Racial differences in responses to interferon-beta-1a in chronic hepatitis C unresponsive to interferon-alpha: a better response in Chinese patients. J Viral Hepat 2004; 11:418-26. [PMID: 15357646 DOI: 10.1111/j.1365-2893.2004.00514.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Re-treatment with interferon-alpha alone for chronic hepatitis C nonresponders to interferon-alpha monotherapy is almost ineffective. This multicentre, randomized, parallel-group, dose-finding study evaluated the efficacy of interferon-beta-1a in the treatment of chronic hepatitis C patients unresponsive to interferon-alpha. A total of 267 patients were randomized to one of four groups: subcutaneous interferon-beta-1a 12 MIU (44 microg) or 24 MIU (88 microg) administered three times weekly or daily. Patients were treated for 48 weeks and then followed up for an additional 24 weeks. There was a trend towards a dose-response relationship regarding virological [loss of detectable serum hepatitis C virus (HCV) RNA] and biochemical response (normalization of serum alanine aminotransferase). Overall, 22 patients (8.3%) had a virological response at the end of treatment; nine patients (3.4%) had a sustained virological response (SVR). Strikingly, 21.7% (5/23) of Chinese patients achieved SVR. Univariate analysis revealed that race was the only variable related to SVR [odds ratio (OR) 16.6; 95% CI 4.1-67.3; P < 0.0001]. Multiple logistic regression analysis also confirmed that more Chinese patients achieved SVR than non-Chinese patients (OR 12.3; 95% CI 2.6-59.3; P = 0.0017). In addition, complete clearance of HCV-RNA occurred earlier in Chinese than in non-Chinese responders (median 2 vs 30 weeks; P = 0.020). Thirty-six patients were withdrawn from treatment because of adverse events. Most adverse events were mild or moderate in severity. In conclusion, interferon-beta-1a provided considerable clinical benefit in Chinese patients with chronic hepatitis C unresponsive to interferon-alpha. The evaluation of interferon-beta-1a in this setting is progressing.
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Affiliation(s)
- P-N Cheng
- Division of Gastroenterology, Department of Internal Medicine, National Cheng Kung University Hospital, Tainan 704, Taiwan
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Rubin BH, Williamson M, Takeshita M, Menger FM, Anet FAL, Bacon B, Allinger NL. Conformation of a saturated 13-membered ring. J Am Chem Soc 2002. [DOI: 10.1021/ja00319a031] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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16
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Niemelä O, Parkkila S, Britton RS, Brunt E, Janney C, Bacon B. Hepatic lipid peroxidation in hereditary hemochromatosis and alcoholic liver injury. J Lab Clin Med 1999; 133:451-60. [PMID: 10235128 DOI: 10.1016/s0022-2143(99)90022-7] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Studies in experimental animals have indicated that enhanced lipid peroxidation may play a role in the hepatic injury produced by iron overload or by excessive alcohol consumption. The aim of this study was to compare the formation of lipid peroxidation-derived aldehydes in the liver of patients with hereditary hemochromatosis (HH) and alcohol abuse. Liver biopsy specimens from 10 nondrinking patients with HH were evaluated. These patients were classified as having HH based on hepatic iron index or human leukocyte antigen identity with a known proband. All patients were homozygous for the Cys282Tyr mutation. In addition, 8 patients with alcoholic liver disease were examined, 2 of whom also had hemochromatosis. For comparison, 17 patients with liver diseases unrelated to iron overload or alcohol abuse were studied. Liver biopsy specimens were immunostained for protein adducts with malondialdehyde and 4-hydroxynonenal. Both malondialdehyde- and 4-hydroxynonenal-protein adducts were found from liver specimens of patients with HH and alcohol abuse in more abundant amounts than from patients in a control group. In alcoholics the adducts were primarily in zone 3, whereas in hemochromatosis staining had an acinar zone 1 predominance, which followed the localization of iron. The most abundant amounts of protein adducts were noted in patients with alcohol abuse plus iron overload. The data support the concept that both chronic alcohol use and iron overload induce hepatic lipid peroxidation. Through formation of reactive aldehydic products, excessive alcohol consumption and iron overload may have additive hepatotoxic effects.
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Affiliation(s)
- O Niemelä
- Department of Clinical Chemistry, University of Oulu, Finland
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17
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Fontana RJ, Keeffe EB, Soldevila C, Lilly L, Luketic V, Kowdley K, Adams P, Jensen D, Bacon B, Wright T, Conjeevaram HS, Perrillo R, Dickson R, Brown RS, Randall-Ray A, Richtmyer P. IS LAMIVUDINE BENEFICIAL IN HBSAG+ PATIENTS AWAITING LIVER TRANSPLANTATION? EXPERIENCE IN 182 NORTH AMERICAN PATIENTS. Transplantation 1999. [DOI: 10.1097/00007890-199904150-00068] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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18
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Abstract
Low dietary intake of the essential trace element selenium can increase the risk of colon cancer. Utilizing RNA arbitrarily primed polymerase chain reaction (RAP-PCR), we sought to identify genes differentially expressed in HT29 human colon adenocarcinoma cells cultured with or without supplemental sodium selenite. One cDNA fragment, present at lower levels in samples from cells supplemented with selenite, had 97% nucleotide sequence identity with a sequence from the 3'-untranslated region of myc-associated zinc-finger protein (MAZ) cDNA. Northern blot analysis showed that steady-state levels of mRNA detected using this fragment as a probe were three times greater in unsupplemented (Se-) than in supplemented (Se+) samples. When a duplicate Northern blot was probed with a 300-bp fragment from the open reading frame of an MAZ cDNA clone, signal intensity was 2.2 times greater in Se- than in Se+ lanes. The MAZ protein has been shown to be a transcription regulator of the c-myc protooncogene. Signal intensity on a Northern blot probed with a segment of c-myc Exon 1 cDNA was 94% greater in Se- than in Se+ lanes. These findings are consistent with the established role for MAZ in regulating c-myc gene expression. They also suggest a molecular mechanism by which selenium intake may affect risk of colon cancer.
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Affiliation(s)
- K K Nelson
- Department of Food Science and Nutrition, Brigham Young University, Provo, UT 84602, USA
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19
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Becherer PR, Bacon B. Hepatitis C testing: interpretation, implications, and counseling. Mo Med 1993; 90:31-35. [PMID: 8421452] [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] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
New molecular biology techniques recently identified hepatitis C virus (HCV) as the major cause of non-A, non-B hepatitis. Serologic assays for HCV specific antibodies are a significant advance, but they require cautious interpretation due to problems with the tests' sensitivity and specificity. Patients with suspected HCV infection should be thoroughly evaluated to verify the presence of infection, to exclude other forms of chronic liver disease, and to determine the extent of liver damage prior to considering treatment.
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Affiliation(s)
- P R Becherer
- St. Louis University Medical Center, Department of Internal Medicine, MO 63104
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Affiliation(s)
- C J McClain
- Department of Medicine, University of Kentucky Medical Center, Lexington, KY 40536
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21
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Yamasaki R, Bacon B. Three-dimensional structural analysis of the group B polysaccharide of Neisseria meningitidis 6275 by two-dimensional NMR: the polysaccharide is suggested to exist in helical conformations in solution. Biochemistry 1991; 30:851-7. [PMID: 1899035 DOI: 10.1021/bi00217a039] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The solution conformations of the group B polysaccharide of Neisseria meningitidis were analyzed by DQF-COSY and pure absorption 2D NOE NMR with three mixing times. The pyranose ring of the sialic acid residue was found to be in the 2C5 conformation. The DQF-COSY analysis indicated that the orientations of H6 and H7 and of H7 and H8 are both gauche. In order to overcome the difficulties in analyzing the NOE data due to the two sets of proton overlaps, molecular modeling of alpha-2,8-linked sialic acid oligomers was carried out to investigate possible conformers, and theoretical NOE calculations were performed by using CORMA (complete relaxation matrix analysis). Our analysis suggests that the polysaccharide adopts helical structures for which the phi (defined by O6-C2-O8-C8) and psi (C2-O8-C8-C7) angles are in the following ranges: phi -60 to 0 degrees, psi 115-175 degrees or phi 90-120 degrees, psi 55-175 degrees. The weak affinity of anti-B antibodies for smaller alpha-2,8-linked oligosaccharides may be due to the fact that such oligomers are more flexible and may not form an ordered structure as the poly(sialic acid) does.
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Affiliation(s)
- R Yamasaki
- Department of Laboratory Medicine, University of California, San Francisco
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22
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Abstract
Because unexplained megaloblastic erythroid maturation occurs in patients with primary refractory sideroblastic anemia (PRSA), deoxyuridine (dU) suppression tests using 125I-UdR were performed on bone marrow from five patients with PRSA. All patients had megaloblastic alterations in the marrow erythroid precursors (with normal serum folate and B12 levels) and numerous ringed sideroblasts, and most had marrow iron overload. Results of the dU suppression tests were normal in all five, both with and without incubation with pharmacologic amounts of folate, B12, and pyridoxal phosphate with or without 1-serine. Despite occasional hematologic improvement subsequent to folate, pyridoxine, or pyridoxal phosphate (PLP) administration in some patients with PRSA, normal dU suppression implies that in our group the availability of B12 and folate (and possibly PLP) was not limiting in the utilization of folate for DNA-thymine synthesis. The marrow erythroid maturation defect remains unexplained.
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el Rifi K, Bacon B, Mehigan J, Hoppe E, Cole WH. Increased incidence of pulmonary metastases after celiotomy: counteraction by heparin. Arch Surg 1965; 91:625-9. [PMID: 5836114 DOI: 10.1001/archsurg.1965.01320160079018] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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