1
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Tam CS, Kapoor P, Castillo JJ, Buske C, Ansell SM, Branagan AR, Kimby E, Li Y, Palomba ML, Qiu L, Shadman M, Abeykoon JP, Sarosiek S, Vos J, Yi S, Stephens D, Roos-Weil D, Roccaro AM, Morel P, Munshi NC, Anderson KC, San-Miguel J, Garcia-Sanz R, Dimopoulos MA, Treon SP, Kersten MJ. Report of consensus panel 7 from the 11th international workshop on Waldenström macroglobulinemia on priorities for novel clinical trials. Semin Hematol 2023; 60:118-124. [PMID: 37099031 DOI: 10.1053/j.seminhematol.2023.03.006] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Accepted: 03/09/2023] [Indexed: 04/27/2023]
Abstract
Recent advances in the understanding of Waldenström macroglobulinemia (WM) biology have impacted the development of effective novel agents and improved our knowledge of how the genomic background of WM may influence selection of therapy. Consensus Panel 7 (CP7) of the 11th International Workshop on WM was convened to examine the current generation of completed and ongoing clinical trials involving novel agents, consider updated data on WM genomics, and make recommendations on the design and prioritization of future clinical trials. CP7 considers limited duration and novel-novel agent combinations to be the priority for the next generation of clinical trials. Evaluation of MYD88, CXCR4 and TP53 at baseline in the context of clinical trials is crucial. The common chemoimmunotherapy backbones, bendamustine-rituximab (BR) and dexamethasone, rituximab and cyclophosphamide (DRC), may be considered standard-of-care for the frontline comparative studies. Key unanswered questions include the definition of frailty in WM; the importance of attaining a very good partial response or better (≥VGPR), within stipulated time frame, in determining survival outcomes; and the optimal treatment of WM populations with special needs.
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Affiliation(s)
- C S Tam
- Alfred Health, Monash University, Melbourne, Victoria, Australia.
| | | | - J J Castillo
- Harvard Medical School, Dana Farber Cancer Institute, Boston. MA
| | - C Buske
- Institute of Experimental Cancer Research, University Hospital Ulm, Ulm, Germany
| | | | | | - E Kimby
- Karolinska Institut, Stockholm, Sweden
| | - Y Li
- Baylor College of Medicine, Houston, TX
| | - M L Palomba
- Memorial Sloan Kettering Cancer Center, New York, NY
| | - L Qiu
- National National Clinical Medical Research Center for Blood Diseases, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, China
| | - M Shadman
- Fred Hutchinson Cancer Research Center, University of Washington, Seattle, WA
| | | | - S Sarosiek
- Harvard Medical School, Dana Farber Cancer Institute, Boston. MA
| | - Jmi Vos
- Department of Hematology, Cancer Center Amsterdam/LYMMCARE, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - S Yi
- National National Clinical Medical Research Center for Blood Diseases, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, China; Tianjin Institutes of Health Science, Tianjin 301600, China
| | - D Stephens
- University of Utah Huntsman Cancer Institute, Salt Lake City, UT
| | - D Roos-Weil
- Sorbonne University, Hematology Unit, Pitié-Salpêtrière Hospital, AP-HP, Paris, France
| | | | - P Morel
- Hematologie Clinique et Therapie Cellulaire, University Hospital Amiens Picardie, University of Picardie Jules Verne, France
| | - N C Munshi
- Institute of Experimental Cancer Research, University Hospital Ulm, Ulm, Germany
| | - K C Anderson
- Institute of Experimental Cancer Research, University Hospital Ulm, Ulm, Germany
| | - J San-Miguel
- Clinica Universidad de Navarra, CCUN, CIMA, IDISNA, CIBERONC, Navarra, Spain
| | - R Garcia-Sanz
- Hematology Department, University Hospital of Salamanca, Research Biomedical Institute of Salamanca, CIBERONC and Center for Cancer Research-IBMCC (University of Salamanca-CSIC), Salamanca, Spain
| | - M A Dimopoulos
- Department of Clinical Therapeutics, National and Kapodistrian University of Athens, Athens, Greece
| | - S P Treon
- Institute of Experimental Cancer Research, University Hospital Ulm, Ulm, Germany
| | - M J Kersten
- Tianjin Institutes of Health Science, Tianjin 301600, China
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2
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D'Sa S, Matous JV, Advani R, Buske C, Castillo JJ, Gatt M, Kapoor P, Kersten MJ, Leblond V, Leiba M, Palomba ML, Paludo J, Qiu L, Sarosiek S, Shadman M, Talaulikar D, Tam CS, Tedeschi A, Thomas SK, Tohidi-Esfahani I, Trotman J, Varettoni M, Vos J, Garcia-Sanz R, San-Miguel J, Dimopoulos MA, Treon SP, Kastritis E. Report of consensus panel 2 from the 11th international workshop on Waldenström's macroglobulinemia on the management of relapsed or refractory WM patients. Semin Hematol 2023; 60:80-89. [PMID: 37147252 DOI: 10.1053/j.seminhematol.2023.03.003] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 03/09/2023] [Indexed: 03/29/2023]
Abstract
The consensus panel 2 (CP2) of the 11th International Workshop on Waldenström's macroglobulinemia (IWWM-11) has reviewed and incorporated current data to update the recommendations for treatment approaches in patients with relapsed or refractory WM (RRWM). The key recommendations from IWWM-11 CP2 include: (1) Chemoimmunotherapy (CIT) and/or a covalent Bruton tyrosine kinase (cBTKi) strategies are important options; their use should reflect the prior upfront strategy and are subject to their availability. (2) In selecting treatment, biological age, co-morbidities and fitness are important; nature of relapse, disease phenotype and WM-related complications, patient preferences and hematopoietic reserve are also critical factors while the composition of the BM disease and mutational status (MYD88, CXCR4, TP53) should also be noted. (3) The trigger for initiating treatment in RRWM should utilize knowledge of patients' prior disease characteristics to avoid unnecessary delays. (4) Risk factors for cBTKi related toxicities (cardiovascular dysfunction, bleeding risk and concurrent medication) should be addressed when choosing cBTKi. Mutational status (MYD88, CXCR4) may influence the cBTKi efficacy, and the role of TP53 disruptions requires further study) in the event of cBTKi failure dose intensity could be up titrated subject to toxicities. Options after BTKi failure include CIT with a non-cross-reactive regimen to one previously used CIT, addition of anti-CD20 antibody to BTKi, switching to a newer cBTKi or non-covalent BTKi, proteasome inhibitors, BCL-2 inhibitors, and new anti-CD20 combinations are additional options. Clinical trial participation should be encouraged for all patients with RRWM.
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Affiliation(s)
- S D'Sa
- UCLH Centre for Waldenström Macroglobulinaemia and Related Conditions, University College London Hospitals NHS Foundation Trust, London, UK.
| | - J V Matous
- Colorado Blood Cancer Institute, Sarah Cannon Research Institute, Denver, CO
| | - R Advani
- Stanford University Medical Center, Stanford, CA
| | - C Buske
- University Hospital Ulm, Ulm, Germany
| | - J J Castillo
- Dana Farber Cancer Institute, Harvard Medical School, Boston, MA
| | - M Gatt
- Hadassah University Medical Center, Jerusalem, Israel
| | | | - M J Kersten
- Amsterdam UMC, University of Amsterdam, Department of Hematology, Cancer Center Amsterdam/LYMMCARE, Amsterdam, Netherlands
| | - V Leblond
- Groupe Hospitalier Pitié-Salpêtrière, Sorbonne University, Paris, France
| | - M Leiba
- Assuta Ashdod University Hospital; Faculty of Health Science, Ben-Gurion University of the Negev, Negev, Israel Memorial Sloan Kettering Cancer Center, New York, NY
| | - M L Palomba
- Memorial Sloan Kettering Cancer Center, New York NY US
| | | | - L Qiu
- National Clinical Medical Research Center for Blood Diseases, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, China
| | - S Sarosiek
- Dana Farber Cancer Institute, Harvard Medical School, Boston, MA
| | | | - D Talaulikar
- ANU College of Health and Medicine, Canberra, Australia
| | - C S Tam
- Alfred Health, Monash University, Melbourne, Australia
| | - A Tedeschi
- A. O. Ospedale Niguarda Ca' Granda, Milan, Italy
| | - S K Thomas
- University of Texas, MD Anderson Cancer Center, Houston TX USA
| | - I Tohidi-Esfahani
- Concord Repatriation General Hospital, University of Sydney, Sydney, Australia
| | - J Trotman
- Concord Repatriation General Hospital, University of Sydney, Sydney, Australia
| | - M Varettoni
- Division of Hematology, Fondazione iRCCS Policlinico, San Matteo, Italy
| | - Jmi Vos
- Amsterdam UMC, University of Amsterdam, Department of Hematology, Cancer Center Amsterdam/LYMMCARE, Amsterdam, Netherlands
| | - R Garcia-Sanz
- Hematology Department, University Hospital of Salamanca, Research Biomedical Institute of Salamanca, CIBERONC and Center for Cancer Research-IBMCC (University of Salamanca-CSIC), Salamanca, Spain
| | - J San-Miguel
- Clínica Universidad de Navarra, Centro de Investigación Médica Aplicada, Instituto de Investigación Sanitaria de Navarra, Centro de Investigación Biomédica en Red Cáncer, Pamplona, Spain
| | - M A Dimopoulos
- Department of Clinical Therapeutics, National and Kapodistrian University of Athens, Athens, Greece
| | - S P Treon
- Dana Farber Cancer Institute, Harvard Medical School, Boston, MA
| | - E Kastritis
- Department of Clinical Therapeutics, National and Kapodistrian University of Athens, Athens, Greece
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3
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Cheah CY, Jurczak W, Lasica M, Wickham N, Wróbel T, Walewski J, Yannakou CK, Cheung S, Lewis KL, Długosz‐Danecka M, Giannopoulos K, Miskin HP, Tang J, Normant E, O'Connor OA, Ricart AD, Tam CS. TG‐1701, A SELECTIVE BRUTON TYROSINE KINASE (BTK) INHIBITOR, AS MONOTHERAPY AND IN COMBINATION WITH UBLITUXIMAB AND UMBRALISIB (U2) IN PATIENTS WITH B‐CELL MALIGNANCIES. Hematol Oncol 2021. [DOI: 10.1002/hon.148_2880] [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: 11/06/2022]
Affiliation(s)
- C. Y Cheah
- Sir Charles Gairdner Hospital Department of Haematology Perth Australia
| | - W Jurczak
- Maria Sklodowska‐Curie National Research Institute of Oncology Oncology Center Krakow Poland
| | - M Lasica
- St. Vincent Hospital and University of Melbourne Haematology Melbourne Australia
| | - N Wickham
- Ashford Cancer Centre Research, Hematology Adelaide Australia
| | - T Wróbel
- Wroclaw Medical University Department of Haematology Blood Neoplasms and Bone Marrow Transplantation Wroclaw Poland
| | - J Walewski
- Maria Sklodowska‐Curie National Research Institute of Oncology Department of Lymphoid Malignancy Warsaw Poland
| | - C. K Yannakou
- Epworth HealthCare Department of Molecular Oncology and Cancer Immunology East Melbourne Australia
| | - S Cheung
- Ashford Cancer Centre Research, Hematology Adelaide Australia
| | - K. L Lewis
- Sir Charles Gairdner Hospital Department of Haematology Perth Australia
| | - M Długosz‐Danecka
- Maria Sklodowska‐Curie National Research Institute of Oncology Oncology Center Krakow Poland
| | - K Giannopoulos
- St John’s Cancer Centre Hematology Department Lublin Poland
| | | | - J.‐P Tang
- TG Therapeutics, Oncology New York USA
| | - E Normant
- TG Therapeutics, Oncology New York USA
| | | | | | - C. S Tam
- St. Vincent Hospital and University of Melbourne Haematology Melbourne Australia
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4
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Cheah CY, Verner E, Tam CS, Hilger J, Gao Y, Huang J, Simpson D, Opat S. PRELIMINARY SAFETY DATA FROM PATIENTS (PTS) WITH RELAPSED/REFRACTORY (R/R) B‐CELL MALIGNANCIES TREATED WITH THE NOVEL B‐CELL LYMPHOMA 2 (BCL2) INHIBITOR BGB‐11417. Hematol Oncol 2021. [DOI: 10.1002/hon.85_2881] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- C. Y. Cheah
- Sir Charles Gairdner Hospital and Pathwest Laboratory Medicine Nedlands; Medical School University of Western Australia Crawley; Linear Clinical Research Department of Haematology Nedlands Australia
| | - E. Verner
- Concord Repatriation General Hospital Concord; University of Sydney Haematology Sydney Australia
| | - C. S. Tam
- Peter MacCallum Cancer Centre Melbourne; University of Melbourne Parkville; St Vincent’s Hospital Fitzroy; Royal Melbourne Hospital Haematology Parkville Australia
| | - J. Hilger
- BeiGene (Beijing) Co., Ltd. Beijing, China and BeiGene USA, Inc. Hematology San Mateo California USA
| | - Y. Gao
- BeiGene (Beijing) Co., Ltd. Beijing, China and BeiGene USA, Inc. Hematology San Mateo California USA
| | - J. Huang
- BeiGene (Beijing) Co., Ltd. Beijing, China and BeiGene USA, Inc. Hematology San Mateo California USA
| | - D. Simpson
- BeiGene (Beijing) Co., Ltd. Beijing, China and BeiGene USA, Inc. Hematology San Mateo California USA
| | - S. Opat
- Monash Health and Monash University Haematology Clayton Australia
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5
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Chin CK, Lim KJ, Lewis K, Jain P, Qing Y, Feng L, Cheah CY, Seymour JF, Ritchie D, Burbury K, Tam CS, Fowler NH, Fayad LE, Westin JR, Neelapu SS, Hagemeister FB, Samaniego F, Flowers CR, Nastoupil LJ, Dickinson MJ. Autologous stem cell transplantation for untreated transformed indolent B-cell lymphoma in first remission: an international, multi-centre propensity-score-matched study. Br J Haematol 2020; 191:806-815. [PMID: 33065767 DOI: 10.1111/bjh.17072] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [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: 06/03/2020] [Accepted: 07/12/2020] [Indexed: 11/30/2022]
Abstract
High-dose chemotherapy (HDC) and autologous stem cell transplantation (ASCT) are used as consolidation in first remission (CR1) in some centres for untreated, transformed indolent B-cell lymphoma (Tr-iNHL) but the evidence base is weak. A total of 319 patients with untreated Tr-iNHL meeting prespecified transplant eligibility criteria [age <75, LVEF ≥45%, no severe lung disease, CR by positron emission tomography or computed tomography ≥3 months after at least standard cyclophosphamide, doxorubicin, vincristine and prednisolone with rituximab (R-CHOP) intensity front-line chemotherapy] were retrospectively identified. Non-diffuse large B-cell lymphoma transformations were excluded. About 283 (89%) patients had follicular lymphoma, 30 (9%) marginal-zone lymphoma and six (2%) other subtypes. Forty-nine patients underwent HDC/ASCT in CR1, and a 1:2 propensity-score-matched cohort of 98 patients based on age, stage and high-grade B-cell lymphoma with MYC, BCL2 and/or BCL6 rearrangements (HGBL-DH) was generated. After a median follow-up of 3·7 (range 0·1-18·3) years, ASCT was associated with significantly superior progression-free survival [hazard ratio (HR) 0·51, 0·27-0·98; P = 0·043] with a trend towards inferior overall survival (OS; HR 2·36;0·87-6·42; P = 0·1) due to more deaths from progressive disease (8% vs. 4%). Forty (41%) patients experienced relapse in the non-ASCT cohort - 15 underwent HDC/ASCT with seven (47%) ongoing complete remission (CR); 10 chimeric antigen receptor-modified T-cell (CAR-T) therapy with 6 (60%) ongoing CR; 3 allogeneic SCT with 2 (67%) ongoing CR. Although ASCT in CR1 improves initial duration of disease control in untreated Tr-iNHL, the impact on OS is less clear with effective salvage therapies in this era of CAR-T.
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Affiliation(s)
- C K Chin
- Department of Lymphoma/Myeloma, University of Texas MD Anderson Cancer Center, Houston, TX, USA.,Department of Clinical Haematology, Peter MacCallum Cancer Centre and Royal Melbourne Hospital, Melbourne, Australia
| | - K J Lim
- Department of Clinical Haematology, Peter MacCallum Cancer Centre and Royal Melbourne Hospital, Melbourne, Australia
| | - K Lewis
- Department of Haematology, Sir Charles Gairdner Hospital, Nedlands, Australia.,Medical School, University of Western Australia, Nedlands, Australia
| | - P Jain
- Department of Lymphoma/Myeloma, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Y Qing
- Department of Biostatistics, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - L Feng
- Department of Biostatistics, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - C Y Cheah
- Department of Haematology, Sir Charles Gairdner Hospital, Nedlands, Australia.,Medical School, University of Western Australia, Nedlands, Australia
| | - J F Seymour
- Department of Clinical Haematology, Peter MacCallum Cancer Centre and Royal Melbourne Hospital, Melbourne, Australia.,The University of Melbourne, Melbourne, Australia
| | - D Ritchie
- Department of Clinical Haematology, Peter MacCallum Cancer Centre and Royal Melbourne Hospital, Melbourne, Australia.,The University of Melbourne, Melbourne, Australia
| | - K Burbury
- Department of Clinical Haematology, Peter MacCallum Cancer Centre and Royal Melbourne Hospital, Melbourne, Australia
| | - C S Tam
- Department of Clinical Haematology, Peter MacCallum Cancer Centre and Royal Melbourne Hospital, Melbourne, Australia.,The University of Melbourne, Melbourne, Australia.,St Vincent's Hospital Melbourne, Melbourne, Australia
| | - N H Fowler
- Department of Lymphoma/Myeloma, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - L E Fayad
- Department of Lymphoma/Myeloma, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - J R Westin
- Department of Lymphoma/Myeloma, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - S S Neelapu
- Department of Lymphoma/Myeloma, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - F B Hagemeister
- Department of Lymphoma/Myeloma, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - F Samaniego
- Department of Lymphoma/Myeloma, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - C R Flowers
- Department of Lymphoma/Myeloma, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - L J Nastoupil
- Department of Lymphoma/Myeloma, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - M J Dickinson
- Department of Clinical Haematology, Peter MacCallum Cancer Centre and Royal Melbourne Hospital, Melbourne, Australia.,The University of Melbourne, Melbourne, Australia
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6
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Martinez-Huenchullan S, McLennan SV, Verhoeven A, Twigg SM, Tam CS. The emerging role of skeletal muscle extracellular matrix remodelling in obesity and exercise. Obes Rev 2017; 18:776-790. [PMID: 28474421 DOI: 10.1111/obr.12548] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [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: 01/18/2017] [Revised: 03/06/2017] [Accepted: 03/13/2017] [Indexed: 01/14/2023]
Abstract
Skeletal muscle extracellular matrix remodelling has been proposed as a new feature associated with obesity and metabolic dysfunction. Exercise training improves muscle function in obesity, which may be mediated by regulatory effects on the muscle extracellular matrix. This review examined available literature on skeletal muscle extracellular matrix remodelling during obesity and the effects of exercise. A non-systematic literature review was performed on PubMed of publications from 1970 to 2015. A total of 37 studies from humans and animals were retained. Studies reported overall increases in gene and protein expression of different types of collagen, growth factors and enzymatic regulators of the skeletal muscle extracellular matrix in obesity. Only two studies investigated the effects of exercise on skeletal muscle extracellular matrix during obesity, with both suggesting a regulatory effect of exercise. The effects of exercise on muscle extracellular matrix seem to be influenced by the duration and type of exercise training with variable effects from a single session compared with a longer duration of exercise. More studies are needed to elucidate the mechanisms behind skeletal muscle extracellular matrix remodelling during obesity and the effects of exercise.
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Affiliation(s)
- S Martinez-Huenchullan
- Greg Brown Diabetes & Endocrinology Laboratory and Charles Perkins Centre, University of Sydney, Sydney, Australia
| | - S V McLennan
- Greg Brown Diabetes & Endocrinology Laboratory and Charles Perkins Centre, University of Sydney, Sydney, Australia.,Department of Endocrinology, Royal Prince Alfred Hospital, Sydney, Australia.,Department of Chemical Pathology, Royal Prince Alfred Hospital, NSW Health Pathology, Sydney, Australia
| | - A Verhoeven
- Greg Brown Diabetes & Endocrinology Laboratory and Charles Perkins Centre, University of Sydney, Sydney, Australia
| | - S M Twigg
- Greg Brown Diabetes & Endocrinology Laboratory and Charles Perkins Centre, University of Sydney, Sydney, Australia.,Department of Endocrinology, Royal Prince Alfred Hospital, Sydney, Australia
| | - C S Tam
- Charles Perkins Centre and School of Life and Environmental Sciences, University of Sydney, Sydney, Australia
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7
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Butler LA, Tam CS, Seymour JF. Dancing partners at the ball: Rational selection of next generation anti-CD20 antibodies for combination therapy of chronic lymphocytic leukemia in the novel agents era. Blood Rev 2017; 31:318-327. [PMID: 28499646 DOI: 10.1016/j.blre.2017.05.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [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: 02/11/2017] [Accepted: 05/02/2017] [Indexed: 02/06/2023]
Abstract
The anti-CD20 antibodies represent a major advancement in the therapeutic options available for chronic lymphocytic leukemia. The addition of rituximab, ofatumumab and obinutuzumab to various chemotherapy regimens has led to considerable improvements in both response and survival. Ocaratuzumab, veltuzumab and ublituximab are currently being explored within the trial setting. We review the current status of these antibodies, and discuss how their mechanisms of action may impact on the choice of combinations with novel small molecule agents.
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Affiliation(s)
- L A Butler
- Peter MacCallum Cancer Centre, 305 Grattan Street, Melbourne, VIC 3000, Australia; Victorian Comprehensive Cancer Centre, 305 Grattan Street, Melbourne, VIC 3000, Australia
| | - C S Tam
- Peter MacCallum Cancer Centre, 305 Grattan Street, Melbourne, VIC 3000, Australia; Victorian Comprehensive Cancer Centre, 305 Grattan Street, Melbourne, VIC 3000, Australia; St. Vincent's Hospital, 41 Victoria Parade, Fitzroy, VIC 3065, Australia; Faculty of Medicine, University of Melbourne, Building 181, Grattan Street, Parkville, VIC 3052, Australia
| | - J F Seymour
- Peter MacCallum Cancer Centre, 305 Grattan Street, Melbourne, VIC 3000, Australia; Victorian Comprehensive Cancer Centre, 305 Grattan Street, Melbourne, VIC 3000, Australia; Faculty of Medicine, University of Melbourne, Building 181, Grattan Street, Parkville, VIC 3052, Australia.
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8
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Braude MR, Trubiano JA, Heriot A, Dickinson M, Carney D, Seymour JF, Tam CS. Disseminated visceral varicella zoster virus presenting with the constellation of colonic pseudo-obstruction, acalculous cholecystitis and syndrome of inappropriate ADH secretion. Intern Med J 2016; 46:238-9. [DOI: 10.1111/imj.12977] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 07/09/2015] [Accepted: 08/02/2015] [Indexed: 12/13/2022]
Affiliation(s)
- M. R. Braude
- General Medicine Department; St Vincent's Hospital Melbourne; Victoria Australia
| | - J. A. Trubiano
- Department of Infectious Diseases; Peter MacCallum Cancer Center; Victoria Australia
| | - A. Heriot
- Hematology Department; Peter MacCallum Cancer Center; East Melbourne Victoria Australia
- The University of Melbourne; Melbourne Victoria Australia
| | - M. Dickinson
- Hematology Department; Peter MacCallum Cancer Center; East Melbourne Victoria Australia
| | - D. Carney
- Hematology Department; Peter MacCallum Cancer Center; East Melbourne Victoria Australia
| | - J. F. Seymour
- Hematology Department; Peter MacCallum Cancer Center; East Melbourne Victoria Australia
- The University of Melbourne; Melbourne Victoria Australia
| | - C. S. Tam
- Hematology Department; Peter MacCallum Cancer Center; East Melbourne Victoria Australia
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9
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van Hal SJ, Gilroy NM, Morrissey CO, Worth LJ, Szer J, Tam CS, Chen SC, Thursky KA, Slavin MA. Survey of antifungal prophylaxis and fungal diagnostic tests employed in malignant haematology and haemopoietic stem cell transplantation (HSCT) in Australia and New Zealand. Intern Med J 2015; 44:1277-82. [PMID: 25482740 DOI: 10.1111/imj.12594] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
This article reports the findings of a survey developed to assess the current use of antifungal prophylaxis among haematology and infectious disease clinicians across Australia and New Zealand, and their alignment with existing consensus guidelines for the use of antifungal agents in the haematology/oncology setting (published 2008). Surveyed clinicians largely followed the current recommendations for prophylaxis in the setting of induction chemotherapy for acute myeloid leukaemia, as well as autologous and low-risk allogeneic haemopoietic stem cell transplantation (HSCT). In keeping with guideline recommendations, posaconazole was the agent used by most centres for high-risk allogeneic HSCT. However, its routine continuation for 75-100 days post-transplantation without de-escalation suggested use beyond those indications described in the 2008 guidelines, namely pre-engraftment neutropenia and graft-versus-host disease. Variations in practice were observed in other settings, such as acute lymphoblastic leukaemia and myelodysplastic syndrome, reflecting the general lack of evidence for antifungal prophylaxis in these patient populations and changing perceptions of risk. With regard to the availability of testing in cases of suspected breakthrough IFD, 40% of centres did not have access to investigative bronchoscopy within 48 h of referral, and results of Aspergillus galactomannan (GM), fungal polymerase chain reaction and therapeutic drug monitoring (TDM) were not available within 48 h in 83%, 90% and 85% of centres respectively. The survey's findings will influence the recommendations provided in the updated 2014 consensus guidelines for the use of antifungal agents in the haematology/oncology setting.
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Affiliation(s)
- S J van Hal
- Department of Microbiology and Infectious Diseases, Royal Prince Alfred Hospital, Camperdown, New South Wales
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10
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Kamel S, Horton L, Ysebaert L, Levade M, Burbury K, Tan S, Cole-Sinclair M, Reynolds J, Filshie R, Schischka S, Khot A, Sandhu S, Keating MJ, Nandurkar H, Tam CS. Ibrutinib inhibits collagen-mediated but not ADP-mediated platelet aggregation. Leukemia 2015; 29:783-7. [PMID: 25138588 DOI: 10.1038/leu.2014.247] [Citation(s) in RCA: 173] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Revised: 08/07/2014] [Accepted: 08/14/2014] [Indexed: 02/03/2023]
Abstract
The BTK (Bruton's tyrosine kinase) inhibitor ibrutinib is associated with an increased risk of bleeding. A previous study reported defects in collagen- and adenosine diphosphate (ADP)-dependent platelet responses when ibrutinib was added ex vivo to patient samples. Whereas the collagen defect is expected given the central role of BTK in glycoprotein VI signaling, the ADP defect lacks a mechanistic explanation. In order to determine the real-life consequences of BTK platelet blockade, we performed light transmission aggregometry in 23 patients receiving ibrutinib treatment. All patients had reductions in collagen-mediated platelet aggregation, with a significant association between the degree of inhibition and the occurrence of clinical bleeding or bruising (P=0.044). This collagen defect was reversible on drug cessation. In contrast to the previous ex vivo report, we found no in vivo ADP defects in subjects receiving standard doses of ibrutinib. These results establish platelet light transmission aggregometry as a method for gauging, at least qualitatively, the severity of platelet impairment in patients receiving ibrutinib treatment.
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Affiliation(s)
- S Kamel
- Department of Hematology, St Vincent's Hospital, Melbourne, Victoria, Australia
| | - L Horton
- Department of Hematology, St Vincent's Hospital, Melbourne, Victoria, Australia
| | - L Ysebaert
- Département d'Hématologie, IUCT-Oncopole, Toulouse, France
| | - M Levade
- 1] Inserm, U1048 and Université Toulouse 3, Toulouse, France [2] Laboratoire d'Hématologie CHU de Toulouse, Toulouse, France
| | - K Burbury
- Department of Hematology, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
| | - S Tan
- Department of Hematology, St Vincent's Hospital, Melbourne, Victoria, Australia
| | - M Cole-Sinclair
- Department of Hematology, St Vincent's Hospital, Melbourne, Victoria, Australia
| | - J Reynolds
- Faculty of Health, Deakin University, Melbourne, Victoria, Australia
| | - R Filshie
- Department of Hematology, St Vincent's Hospital, Melbourne, Victoria, Australia
| | - S Schischka
- Department of Hematology, St Vincent's Hospital, Melbourne, Victoria, Australia
| | - A Khot
- Department of Hematology, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
| | - S Sandhu
- Department of Hematology, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
| | - M J Keating
- Leukemia Department, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - H Nandurkar
- 1] Department of Hematology, St Vincent's Hospital, Melbourne, Victoria, Australia [2] University of Melbourne, Parkville, Victoria, Australia
| | - C S Tam
- 1] Department of Hematology, St Vincent's Hospital, Melbourne, Victoria, Australia [2] Department of Hematology, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia [3] University of Melbourne, Parkville, Victoria, Australia
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11
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Fleming S, Yannakou CK, Haeusler GM, Clark J, Grigg A, Heath CH, Bajel A, van Hal SJ, Chen SC, Milliken ST, Morrissey CO, Tam CS, Szer J, Weinkove R, Slavin MA. Consensus guidelines for antifungal prophylaxis in haematological malignancy and haemopoietic stem cell transplantation, 2014. Intern Med J 2014; 44:1283-97. [DOI: 10.1111/imj.12595] [Citation(s) in RCA: 95] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- S. Fleming
- Malignant Haematology and Stem Cell Transplantation Service; Alfred Health; Prahran Victoria
| | - C. K. Yannakou
- Department of Clinical Haematology and Bone Marrow Transplant Service; The Royal Melbourne Hospital; Parkville Victoria
| | - G. M. Haeusler
- Department of Infectious Diseases and Infection Control; Peter MacCallum Cancer Centre; East Melbourne Victoria
- Department of Paediatric Infectious Diseases; Monash Children's Hospital; Monash Health; Clayton Victoria
- Paediatric Integrated Cancer Service; Parkville Victoria
| | - J. Clark
- Infection Management and Prevention Service; The Royal Children's Hospital Brisbane; Queensland Health; Herston Queensland
| | - A. Grigg
- Department of Clinical Haematology; Austin Health; Heidelberg Victoria
- School of Medicine; The University of Melbourne; Melbourne Victoria
| | - C. H. Heath
- Department of Microbiology and Infectious Diseases; Royal Perth Hospital; Perth Western Australia
- School of Medicine and Pharmacology (RPH Unit); University of Western Australia; Perth Western Australia
| | - A. Bajel
- Department of Clinical Haematology and Bone Marrow Transplant Service; The Royal Melbourne Hospital; Parkville Victoria
| | - S. J. van Hal
- Department of Microbiology and Infectious Diseases; Royal Prince Alfred Hospital; Camperdown New South Wales
| | - S. C. Chen
- Centre for Infectious Diseases and Microbiology Laboratory Services; ICPMR - Pathology West; Westmead New South Wales
- Department of Infectious Diseases; Westmead Hospital; Westmead New South Wales
- Sydney Medical School; The University of Sydney; Sydney New South Wales
| | - S. T. Milliken
- Department of Haematology; St Vincent's Hospital; Darlinghurst New South Wales
- Faculties of Medicine and Pathology; The University of NSW; Kensington New South Wales
| | - C. O. Morrissey
- Department of Infectious Diseases; Alfred Health and Monash University; Prahran Victoria
- Department of Clinical Haematology; Alfred Health; Prahran Victoria
| | - C. S. Tam
- School of Medicine; The University of Melbourne; Melbourne Victoria
- Department of Haematology; Peter MacCallum Cancer Centre; East Melbourne Victoria
| | - J. Szer
- Department of Clinical Haematology and Bone Marrow Transplant Service; The Royal Melbourne Hospital; Parkville Victoria
- School of Medicine; The University of Melbourne; Melbourne Victoria
| | - R. Weinkove
- Wellington Blood and Cancer Centre; Capital and Coast District Health Board; Wellington New Zealand
- Vaccine Research Group; Malaghan Institute of Medical Research; Wellington New Zealand
| | - M. A. Slavin
- Department of Infectious Diseases and Infection Control; Peter MacCallum Cancer Centre; East Melbourne Victoria
- School of Medicine; The University of Melbourne; Melbourne Victoria
- Victorian Infectious Diseases Service; The Doherty Institute for Infection and Immunity; Parkville Victoria
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12
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Cheah CY, Herbert KE, O'Rourke K, Kennedy GA, George A, Fedele PL, Gilbertson M, Tan SY, Ritchie DS, Opat SS, Prince HM, Dickinson M, Burbury K, Wolf M, Januszewicz EH, Tam CS, Westerman DA, Carney DA, Harrison SJ, Seymour JF. A multicentre retrospective comparison of central nervous system prophylaxis strategies among patients with high-risk diffuse large B-cell lymphoma. Br J Cancer 2014; 111:1072-9. [PMID: 25072255 PMCID: PMC4453849 DOI: 10.1038/bjc.2014.405] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Revised: 06/04/2014] [Accepted: 06/23/2014] [Indexed: 01/17/2023] Open
Abstract
Background: Central nervous system (CNS) relapse in diffuse large B-cell lymphoma (DLBCL) is a devastating complication; the optimal prophylactic strategy remains unclear. Methods: We performed a multicentre, retrospective analysis of patients with DLBCL with high risk for CNS relapse as defined by two or more of: multiple extranodal sites, elevated serum LDH and B symptoms or involvement of specific high-risk anatomical sites. We compared three different strategies of CNS-directed therapy: intrathecal (IT) methotrexate (MTX) with (R)-CHOP ‘group 1' R-CHOP with IT MTX and two cycles of high-dose intravenous (IV) MTX ‘group 2' dose-intensive systemic antimetabolite-containing chemotherapy (Hyper-CVAD or CODOXM/IVAC) with IT/IV MTX ‘group 3'. Results: Overall, 217 patients were identified (49, 125 and 43 in groups 1–3, respectively). With median follow-up of 3.4 (range 0.2–18.6) years, 23 CNS relapses occurred (12, 10 and 1 in groups 1–3 respectively). The 3-year actuarial rates (95% CI) of CNS relapse were 18.4% (9.5–33.1%), 6.9% (3.5–13.4%) and 2.3% (0.4–15.4%) in groups 1–3, respectively (P=0.009). Conclusions: The addition of high-dose IV MTX and/or cytarabine was associated with lower incidence of CNS relapse compared with IT chemotherapy alone. However, these data are limited by their retrospective nature and warrant confirmation in prospective randomised studies.
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Affiliation(s)
- C Y Cheah
- 1] Department of Haematology, Peter MacCallum Cancer Centre, Locked Bag 1, A'Beckett Street, Melbourne, Victoria 8006, Australia [2] Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia
| | - K E Herbert
- 1] Department of Haematology, Peter MacCallum Cancer Centre, Locked Bag 1, A'Beckett Street, Melbourne, Victoria 8006, Australia [2] Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia [3] Cabrini Medical Centre, Malvern, Victoria, Australia
| | - K O'Rourke
- Department of Haematology, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia
| | - G A Kennedy
- 1] Department of Haematology, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia [2] University of Queensland, St Lucia, Queensland, Australia
| | - A George
- Department of Haematology, Peter MacCallum Cancer Centre, Locked Bag 1, A'Beckett Street, Melbourne, Victoria 8006, Australia
| | - P L Fedele
- Department of Haematology, Monash Health, Clayton, Victoria, Australia
| | - M Gilbertson
- 1] Department of Haematology, Monash Health, Clayton, Victoria, Australia [2] Department of Haematology, Monash University, Clayton, Victoria, Australia
| | - S Y Tan
- Department of Haematology, Monash Health, Clayton, Victoria, Australia
| | - D S Ritchie
- 1] Department of Haematology, Peter MacCallum Cancer Centre, Locked Bag 1, A'Beckett Street, Melbourne, Victoria 8006, Australia [2] Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia
| | - S S Opat
- 1] Department of Haematology, Monash Health, Clayton, Victoria, Australia [2] Department of Haematology, Monash University, Clayton, Victoria, Australia
| | - H M Prince
- 1] Department of Haematology, Peter MacCallum Cancer Centre, Locked Bag 1, A'Beckett Street, Melbourne, Victoria 8006, Australia [2] Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia [3] Cabrini Medical Centre, Malvern, Victoria, Australia [4] Department of Haematology, Monash University, Clayton, Victoria, Australia
| | - M Dickinson
- 1] Department of Haematology, Peter MacCallum Cancer Centre, Locked Bag 1, A'Beckett Street, Melbourne, Victoria 8006, Australia [2] Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia
| | - K Burbury
- 1] Department of Haematology, Peter MacCallum Cancer Centre, Locked Bag 1, A'Beckett Street, Melbourne, Victoria 8006, Australia [2] Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia
| | - M Wolf
- 1] Department of Haematology, Peter MacCallum Cancer Centre, Locked Bag 1, A'Beckett Street, Melbourne, Victoria 8006, Australia [2] Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia [3] Cabrini Medical Centre, Malvern, Victoria, Australia
| | - E H Januszewicz
- Department of Haematology, Peter MacCallum Cancer Centre, Locked Bag 1, A'Beckett Street, Melbourne, Victoria 8006, Australia
| | - C S Tam
- 1] Department of Haematology, Peter MacCallum Cancer Centre, Locked Bag 1, A'Beckett Street, Melbourne, Victoria 8006, Australia [2] Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia
| | - D A Westerman
- 1] Department of Haematology, Peter MacCallum Cancer Centre, Locked Bag 1, A'Beckett Street, Melbourne, Victoria 8006, Australia [2] Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia
| | - D A Carney
- 1] Department of Haematology, Peter MacCallum Cancer Centre, Locked Bag 1, A'Beckett Street, Melbourne, Victoria 8006, Australia [2] Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia
| | - S J Harrison
- 1] Department of Haematology, Peter MacCallum Cancer Centre, Locked Bag 1, A'Beckett Street, Melbourne, Victoria 8006, Australia [2] Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia
| | - J F Seymour
- 1] Department of Haematology, Peter MacCallum Cancer Centre, Locked Bag 1, A'Beckett Street, Melbourne, Victoria 8006, Australia [2] Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia
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13
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Lee WY, Tam CS, Yan PY, Lam YY, Duchatelet S, Peat RA, Denjoy I, Itoh H, Berthet M, Crotti L, Ohno S, Pedrazzini M, Klug D, Schwartz PJ, Shimizu W, Horie M, Tregouet DA, Guicheney P, Tiong WN, Hwang SS, Fong AYY, Wee CC, Lai LYH, Tiong LL, Chang BC, Ong TK, Garg P, Ashraffi R, Chuah S, Baho H, Draz S, Mously F, Atta J, Kouatly A, Hussian A, Abu zeid H, Courtney A, Hamilton-Craig C, Strugnell W, Slaughter R, Luis CR, Habibian M, Luis SA, Raffel OC, Tung TH, Hsiung MC, Wei J, Clements IP, Hodge DO, Scott CG, Chai SC, Liew M, Leong G, Peng H, Ding J, Peng Y, Zhang Q, Xu Y, Chao X, Tian H, Zhang Y, Liu Y, Tong WJ, Liu YY, Wang J, Zhang YH, Wong MCS, Yan B, Tam WWS, Wang HHX, Liu KSD, Liu KQ, Cheung CSK, Tong ELH, Sek ACH, Cheung NT, Yu CM, Leeder S, Griffiths S, Poon KKC, Wong HL, Ng SH, Kwok WT, Yeung CL, Yu SY, Wan YP, Wan S, Underwood MJ, Chan PH, Alegria-Barrero E, Price S, Kelleher A, Moat N, Mario CD, Franzen O, Zhang YC, Lee AP, Lin QS, Fang F, Wan S, Underwood M, Yu CM, Mirhoseini SJ, Frouzannia SK, Mostafavi Pour Manshadi SMY, Naderi N, Sayegh S, Dandekar PG, Verma Y. A001 * Barriers of warfarin use for atrial fibrillation patients in Hong Kong. Eur Heart J Suppl 2012. [DOI: 10.1093/eurheartj/sur021] [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: 11/14/2022]
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14
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Tam CS, Berthoud HR, Bueter M, Chakravarthy MV, Geliebter A, Hajnal A, Holst J, Kaplan L, Pories W, Raybould H, Seeley R, Strader A, Ravussin E. Could the mechanisms of bariatric surgery hold the key for novel therapies? report from a Pennington Scientific Symposium. Obes Rev 2011; 12:984-94. [PMID: 21729236 PMCID: PMC4048708 DOI: 10.1111/j.1467-789x.2011.00902.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [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: 01/04/2023]
Abstract
Bariatric surgery is the most effective method for promoting dramatic and durable weight loss in morbidly obese subjects. Furthermore, type 2 diabetes is resolved in over 80% of patients. The mechanisms behind the amelioration in metabolic abnormalities are largely unknown but may be due to changes in energy metabolism, gut peptides and food preference. The goal of this meeting was to review the latest research to better understand the mechanisms behind the 'magic' of bariatric surgery. Replication of these effects in a non-surgical manner remains one of the ultimate challenges for the treatment of obesity and diabetes. Promising data on energy metabolism, gastrointestinal physiology, hedonic response and food intake were reviewed and discussed.
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Affiliation(s)
- C S Tam
- Pennington Biomedical Research Center, Baton Rouge, LA 70808, USA
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15
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Tam CS, O'Reilly M, Andresen D, Lingaratnam S, Kelly A, Burbury K, Turnidge J, Slavin MA, Worth LJ, Dawson L, Thursky KA. Use of empiric antimicrobial therapy in neutropenic fever. Australian Consensus Guidelines 2011 Steering Committee. Intern Med J 2011; 41:90-101. [PMID: 21272173 DOI: 10.1111/j.1445-5994.2010.02340.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Administration of empiric antimicrobial therapy is standard practice in the management of neutropenic fever, but there remains considerable debate about the selection of an optimal regimen. In view of emerging evidence regarding efficacy and toxicity differences between empiric treatment regimens, and strong evidence of heterogeneity in clinical practice, the current guidelines were developed to provide Australian clinicians with comprehensive guidance for selecting an appropriate empiric strategy in the setting of neutropenic fever. Beta-lactam monotherapy is presented as the treatment of choice for all clinically stable patients while early treatment with combination antibiotic therapy is considered for patients at higher risk. Due consideration is given to the appropriate use of glycopeptides in this setting. Several clinical caveats, accounting for institution- and patient-specific risk factors, are provided to help guide the judicious use of the agents described. Detailed recommendations are also provided regarding time to first dose, timing of blood cultures, selection of a first-line antibiotic regimen, subsequent modification of antibiotic choice and cessation of therapy.
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Affiliation(s)
- C S Tam
- St Vincent's Hospital, Melbourne, Victoria, Australia
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16
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Carney DA, Westerman DA, Tam CS, Milner A, Prince HM, Kenealy M, Wolf M, Januszewicz EH, Ritchie D, Came N, Seymour JF. Therapy-related myelodysplastic syndrome and acute myeloid leukemia following fludarabine combination chemotherapy. Leukemia 2010; 24:2056-62. [DOI: 10.1038/leu.2010.218] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Samocha-Bonet D, Campbell LV, Viardot A, Freund J, Tam CS, Greenfield JR, Heilbronn LK. A family history of type 2 diabetes increases risk factors associated with overfeeding. Diabetologia 2010; 53:1700-8. [PMID: 20461357 DOI: 10.1007/s00125-010-1768-y] [Citation(s) in RCA: 45] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2010] [Accepted: 03/30/2010] [Indexed: 10/19/2022]
Abstract
AIMS/HYPOTHESIS The purpose of the study was to test prospectively whether healthy individuals with a family history of type 2 diabetes are more susceptible to adverse metabolic effects during experimental overfeeding. METHODS We studied the effects of 3 and 28 days of overfeeding by 5,200 kJ/day in 41 sedentary individuals with and without a family history of type 2 diabetes (FH+ and FH- respectively). Measures included body weight, fat distribution (computed tomography) and insulin sensitivity (hyperinsulinaemic-euglycaemic clamp). RESULTS Body weight was increased compared with baseline at 3 and 28 days in both groups (p < 0.001), FH+ individuals having gained significantly more weight than FH- individuals at 28 days (3.4 +/- 1.6 vs 2.2 +/- 1.4 kg, p < 0.05). Fasting serum insulin and C-peptide were increased at 3 and 28 days compared with baseline in both groups, with greater increases in FH+ than in FH- for insulin at +3 and +28 days (p < 0.01) and C-peptide at +28 days (p < 0.05). Fasting glucose also increased at both time points, but without a significant group effect (p = 0.1). Peripheral insulin sensitivity decreased in the whole cohort at +28 days (54.8 +/- 17.7 to 50.3 +/- 15.6 micromol min(-1) [kg fat-free mass](-1), p = 0.03), and insulin sensitivity by HOMA-IR decreased at both time points (p < 0.001) and to a greater extent in FH+ than in FH- (p = 0.008). Liver fat, subcutaneous and visceral fat increased similarly in the two groups (p < 0.001). CONCLUSIONS Overfeeding induced weight and fat gain, insulin resistance and hepatic fat deposition in healthy individuals. However, individuals with a family history of type 2 diabetes gained more weight and greater insulin resistance by HOMA-IR. The results of this study suggest that healthy individuals with a family history of type 2 diabetes are predisposed to adverse effects of overfeeding. TRIAL REGISTRATION ClinicalTrials.gov NCT00562393 FUNDING The study was funded by the National Health and Medical Research Council (NHMRC), Australia (no. #427639).
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Affiliation(s)
- D Samocha-Bonet
- Diabetes and Obesity Program, Garvan Institute of Medical Research, Darlinghurst, NSW, Australia
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18
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Tam CS. In defence of the use of modern chemotherapy regimens for the treatment of patients with chronic lymphocytic leukaemia. Intern Med J 2010; 39:858-9. [PMID: 20233254 DOI: 10.1111/j.1445-5994.2009.02071.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
Childhood obesity is a major public health problem. Low-grade inflammation, a hallmark characterizing adult obesity, may be a pivotal mechanism linking obesity to its numerous systemic complications, with adipose tissue depots secreting and producing inflammatory mediators and visceral fat displaying an increased inflammatory profile. While knowledge is relatively scarce regarding the importance of the adipose tissue inflammation process in children, identifying its contribution in childhood obesity and the associated influences of age, sex, weight status, growth, and adipose depot phenotypes are crucial for understanding physiopathology and implementing early intervention strategies. We review the latest research linking obesity and inflammation in childhood focusing on serum inflammatory markers and the effectiveness of lifestyle interventions in improving systemic inflammation. Generally, there are significant correlations between body mass index and increased c-reactive protein and decreased adiponectin levels in children; these levels tend to be improved in interventions resulting in approximately 5% weight loss, regardless of the type or length of intervention. There is a need for further research measuring other inflammatory mediators (e.g. tumour necrosis factor (TNF)-alpha, IL-6, IL-8) and histological studies examining immune cell infiltration in adipose tissue depots in obese children.
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Affiliation(s)
- C S Tam
- Institute of Endocrinology and Diabetes, The Children's Hospital at Westmead, Westmead, NSW, Australia.
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20
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Tam CS, Wierda W, O'Brien SM, Lerner S, Abruzzo LV, Ferrajoli A, Kantarjian HM, Keating MJ. The clinical significance of chromosome 17p deletion in chronic lymphocytic leukemia: A study of 180 consecutive patients. J Clin Oncol 2008. [DOI: 10.1200/jco.2008.26.15_suppl.7035] [Citation(s) in RCA: 3] [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: 11/20/2022] Open
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Tam CS, O'Brien S, Wierda W, Lerner S, Kantarjian H, Keating MJ. Seventy percent of complete responders remain in continuous remission: Five-year follow-up of 300 patients treated with fludarabine, cyclophosphamide, and rituximab (FCR) as initial therapy of CLL. J Clin Oncol 2007. [DOI: 10.1200/jco.2007.25.18_suppl.7008] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
7008 Background: The early results of 224 CLL patients receiving the FCR regimen were previously reported (JCO 23:4079). Mature follow-up data (median 62 months for survivors) is now available for the complete cohort of 300 patients. Methods: Eligible patients were =16 years old with previously untreated CLL requiring therapy. Median age was 57 years (31%=60 years, 14% =70 years), and 61% & 36% were in modified Rai intermediate & high risk categories respectively. Prognostic factors: B2m >2x normal 42% (n=295), CD38 positive 28% (n=253), abnormal metaphase cytogenetics 29% (n=221), IgVH unmutated 66% (n=94), ZAP-70 positive 49% (n=88). The planned six cycles of therapy were completed in 74% patients. Results: Responses were: 72% CR, 11% nodular PR (PRn) & 12% PR. On multivariate analysis, CR rates were inferior in patients with B2m >2N (p=0.001) and white cell count >150 × 109/L (p=0.01). Rai stage, CD38 positivity, IGVH mutational status and ZAP-70 positivity were not associated with inferior CR. Median Times to Progression (TTP) were 80 months for CR (n=216), 80 months for PRn (n=32) & 27 months for PR (n=36), with 77%, 65% and 28% projected to be progression-free at five years; projected 5 yr survival were 90%, 81% and 37% respectively. Restricting the analysis to 190 patients with at least five years followup, actual 5 yr TTP and 5yr survival were 70% & 88% respectively in complete responders. Five cases of Richter transformation and eight cases of MDS/AML occurred during remission, with projected 5 yr risk of 2% & 3% respectively. When compared with a historical cohort of patients receiving fludarabine (n=190) or fludarabine and cyclophosphamide/mitoxantrone (n=140) in multivariate analysis, FCR was independently associated with superior TTP (p<0.001) and survival (p<0.001). Conclusion: FCR is the most effective CLL frontline regimen reported to date. 70% of complete responders remain progression-free at five years. No significant financial relationships to disclose.
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Affiliation(s)
- C. S. Tam
- UT MD Anderson Cancer Center, Houston, TX
| | - S. O'Brien
- UT MD Anderson Cancer Center, Houston, TX
| | - W. Wierda
- UT MD Anderson Cancer Center, Houston, TX
| | - S. Lerner
- UT MD Anderson Cancer Center, Houston, TX
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22
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Tam CS, Garnett SP, Cowell CT, Campbell K, Cabrera G, Baur LA. Soft drink consumption and excess weight gain in Australian school students: results from the Nepean study. Int J Obes (Lond) 2006; 30:1091-3. [PMID: 16801946 DOI: 10.1038/sj.ijo.0803328] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [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: 11/09/2022]
Abstract
We studied the relation between soft drink/cordial (a sweet, flavoured, concentrated syrup that is mixed with water to taste), fruit juice/drink and milk consumption in mid-childhood, and body mass index (BMI) status in early adolescence in a contemporary Australian cohort. In 1996/7, 268 children (136 males) were recruited from western Sydney at baseline (mean+/-s.d.: 7.7+/-0.6 years), and at follow-up 5 years later (13.0+/-0.2 years). Height and weight were measured at both time periods and overweight and obesity defined using the International Obesity TaskForce criteria. Beverage consumption was calculated from a 3-day food record at baseline. Median carbohydrate intake from soft drink/cordial was 10 g higher (P=0.002) per day in children who were overweight/obese at follow-up compared to those who had an acceptable BMI at both baseline and follow-up. Intakes of soft drink/cordial in mid-childhood, but not fruit juice/fruit drink and milk, were associated with excess weight gain in early adolescence.
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Affiliation(s)
- C S Tam
- Institute of Diabetes and Endocrinology, The Children's Hospital at Westmead, Westmead, NSW, Australia.
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23
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Tam CS, Galanos J, Seymour JF, Pitman AG, Stark RJ, Prince HM. Reversible posterior leukoencephalopathy syndrome complicating cytotoxic chemotherapy for hematologic malignancies. Am J Hematol 2004; 77:72-6. [PMID: 15307110 DOI: 10.1002/ajh.20147] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.4] [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: 12/16/2022]
Abstract
Reversible posterior leukoencephalopathy syndrome (RPLS) is an uncommon but distinctive clinicoradiological entity comprising of headache, seizures, visual disturbance, and altered mental function, in association with posterior cerebral white matter edema. With appropriate management, RPLS is reversible in the majority of cases. Previous reported associations of RPLS include hypertension, eclampsia, renal failure, and use of immunosuppressive drugs; reports in the adult hematology setting are rare. We report two cases of adults undergoing treatment for hematological malignancies who developed RPLS, and we emphasize the importance of early recognition and institution of appropriate management in reducing the risk of development of permanent neurological disability.
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Affiliation(s)
- C S Tam
- Hematology Service, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
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Abstract
This study investigates the responses of the fourth and fifth lumbar vertebral bodies of 6-month-old male Sprague-Dawley (SD) rats to orchidectomy (orx) and to erect bipedal stance for feeding for 12 weeks in specially designed raised cages (RC) for which the heights were raised from 20 cm to 35.5 cm. A total of 30 rats were divided into groups of: baseline; sham + housed in normal height cage (NC); orx + NC; sham + RC; and orx + RC. Bone histomorphometry was performed on the triple-labeled undecalcified fourth sagittal (LVL-4) and fifth transverse (LVX-5) sections. We found that orchidectomy induced high-turnover trabecular and cortical bone loss in the lumbar vertebrae. Forcing the rats to rise to erect stance for feeding reduced trabecular and cortical bone loss caused by orx. Apparently, depressing the elevated bone resorption next to the marrow induced by orx, and stimulating bone formation at the ventral periosteal surfaces, caused these effects. Orchidectomy and raised cage had similar effects on the two vertebrae except that the percentage of trabecular bone loss was greater in the LVL-4 than in LVX-5, and that bipedal stance exercise increased the total tissue area and mineral apposition rates (0-80 day interval) of ventral periosteal and dorsal endocortical surfaces of LVX-5 to a greater extent than it did in LVL-4. Such findings suggest that forcing rats to rise to an erect bipedal stance for feeding helps prevent loss of trabecular and cortical bone "mass," and presumably bone strength, in orchidectomized rats. This method also provides an inexpensive, noninvasive, reliable model to increase in vivo vertebral loading in rats that is similar in humans.
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Affiliation(s)
- W Yao
- Radiobiology Division, University of Utah, Salt Lake City, UT 84108-1218, USA.
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Yao W, Jee WS, Chen J, Liu H, Tam CS, Cui L, Zhou H, Setterberg RB, Frost HM. Making rats rise to erect bipedal stance for feeding partially prevented orchidectomy-induced bone loss and added bone to intact rats. J Bone Miner Res 2000; 15:1158-68. [PMID: 10841185 DOI: 10.1359/jbmr.2000.15.6.1158] [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] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The objectives of this study were to investigate the different effects on muscle mass and cancellous (proximal tibial metaphysis [PTM]) and cortical (tibial shaft [TX]) bone mass of sham-operated and orchidectomized (ORX) male rats by making rats rise to erect bipedal stance for feeding. Specially designed raised cages (RC) were used so that the rats had to rise to erect bipedal stance to eat and drink for 12 weeks. Dual-energy X-ray absorptiometry (DEXA) and peripheral quantitative computerized tomography (pQCT) were used to estimate the lean leg mass and bone mineral. Static and dynamic histomorphometry were performed on the triple-labeled undecalcified sections. We found that making the intact rats rise to erect bipedal stance for feeding increased muscle mass, cortical bone volume, and periosteal bone formation. Orchidectomy increased net losses of bone next to the marrow by increasing bone turnover. Making the ORX rats rise to erect bipedal stance increased muscle mass, partially prevented cancellous bone loss in the PTM, and prevented net cortical bone loss in TX induced by ORX by depressing cancellous and endocortical high bone turnover and stimulating periosteal bone formation. The bone-anabolic effects were achieved mainly in the first 4 weeks in the PTM and by 8 weeks in the TX. These findings suggested that making the rats rise to erect bipedal stance for feeding helped to increase muscle mass and cortical bone mass in the tibias of intact rats, increase muscle mass, and partially prevented cancellous and net cortical bone loss in ORX rats.
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Affiliation(s)
- W Yao
- Radiobiology Division, University of Utah, Salt Lake City 84108-1218, USA
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Murray TM, Rao LG, Wong MM, Waddell JP, McBroom R, Tam CS, Rosen F, Levine MA. Pseudohypoparathyroidism with osteitis fibrosa cystica: direct demonstration of skeletal responsiveness to parathyroid hormone in cells cultured from bone. J Bone Miner Res 1993; 8:83-91. [PMID: 8427051 DOI: 10.1002/jbmr.5650080111] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.4] [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] [Indexed: 01/30/2023]
Abstract
A young girl had tibial osteotomies at age 14 for genu valgum and then had recurrent tibial cysts over a number of years. Hypocalcemia and hyperphosphatemia were first noted at age 21. The diagnosis of pseudohypoparathyroidism was made at age 28, when elevated plasma PTH was detected. Clinical and biochemical features, including a PTH response test and assay of RBC Gs, established the diagnosis of pseudohypoparathyroidism type 1b. Failure to suppress plasma PTH with vitamin D therapy led to an exacerbation of her cystic bone disease; there were widespread lytic lesions radiologically, most of which took up [99mTc]diphosphonate on bone scan. Microradioscopy revealed evidence of resorption of phalangeal tufts. Bone biopsy showed osteitis fibrosa cystica. During an orthopedic procedure, trabecular bone fragments were taken from her right humerus, and bone-derived cells cultured using an explant technique. The cultured cells were osteoblast-like in morphology, fully responsive to PTH, cholera toxin, forskolin, and PGE1 in vitro, and had an alkaline phosphatase and osteocalcin response to 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3]. Following this examination of skeletal responsiveness, attempts were made to suppress the elevated plasma PTH levels and symptomatic bone disease by optimizing therapy with oral 1,25-(OH)2D3. When bone pain associated with the cystic bone disease failed to resolve, the patient underwent total parathyroidectomy, following which the bone pain gradually resolved. This is the first direct demonstration of PTH responsiveness in cultured bone cells in the syndrome of pseudohypoparathyroidism with osteitis fibrosa cystica.
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Affiliation(s)
- T M Murray
- Division of Endocrinology and Metabolism, St. Michael's Hospital, Ontario, Canada
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Rabbani SA, Yasuda T, Bennett HP, Sung WL, Zahab DM, Tam CS, Goltzman D, Hendy GN. Recombinant human parathyroid hormone synthesized in Escherichia coli. Purification and characterization. J Biol Chem 1988; 263:1307-13. [PMID: 3275665] [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: 01/05/2023] Open
Abstract
Recombinant human parathyroid hormone (hPTH) was expressed in Escherichia coli harboring a plasmid containing a synthetic human parathyroid hormone gene under the control of the E. coli lac promoter. Three major forms of the hormone were isolated by acid extraction and purified to homogeneity by high performance liquid chromatography. By amino acid analysis and NH2-terminal sequencing, these were identified as hPTH-(1-84), formyl-methionyl-hPTH-(1-84), and hPTH-(8-84). The recombinant hPTH-(1-84) was immunologically indistinguishable from a World Health Organization standard of extracted native hPTH-(1-84). Recombinant hPTH-(1-84) was also bioactive in renal and skeletal adenylate cyclase assays. In the skeletal bioassay performed in UMR 108 osteosarcoma cells its activity was identical to that of an hPTH-(1-84) standard. In this bioassay, formyl-methionyl-hPTH-(1-84) had 10% of the activity of hPTH-(1-84) and hPTH-(8-84) was inactive. The results demonstrate the importance of isolating hPTH-(1-84) from other recombinant forms and metabolites to achieve full hormonal bioactivity and indicate that purified recombinant hPTH-(1-84) can thereby be obtained which should be a useful source of hormone for both basic and clinical studies.
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Affiliation(s)
- S A Rabbani
- Department of Medicine, McGill University, Montreal, Quebec, Canada
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Rabbani SA, Yasuda T, Bennett HP, Sung WL, Zahab DM, Tam CS, Goltzman D, Hendy GN. Recombinant human parathyroid hormone synthesized in Escherichia coli. Purification and characterization. J Biol Chem 1988. [DOI: 10.1016/s0021-9258(19)57301-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Abstract
The linear rate of bone mineral apposition (BMAR) was measured in vitamin D-deficient and vitamin D-sufficient adult rats before and during treatment with either 25-hydroxyvitamin D3 (25OHD3), 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3], or 24,25-dihydroxyvitamin D3 [24,25-(OH)2D3]. Dietary vitamin D restriction caused a fall in BMAR which began after 1 week and fell progressively to a value of 35-50% of control values by 4 weeks. The fall in BMAR was related to a fall in the serum concentrations of 25(OH)D3 and 24,25-(OH)2D3, without a fall in the 1,25-(OH)2D3 concentration. Dietary supplementation of the D-deficient animals with either 25OHD3 or 24,25-(OH)2D3 at doses of 200 ng/day restored BMAR. If vitamin D-deficient animals were thyroparathyroid-ectomized before supplementation with vitamin D metabolites, 24,25-(OH)2D3 administration was without effect on BMAR. The combined administration of PTH and 24,25-(OH)2D3 to such animals led to a restoration of the BMAR to normal. In vitamin D-sufficient animals, parathyroidectomy led to a 50% reduction in BMAR, which could be restored by treatment with PTH alone but not with 24,25-(OH)2D3. Simultaneous treatment of these animals with PTH and 24,25-(OH)2D3 led to a greater than normal increase in BMAR (130% of control) in these animals. These data support the concept that 24,25-(OH)2D3 has a role in the regulation of bone formation and/or mineralization, and demonstrate the interrelation between the effects of PTH and 24,25-(OH)2D3 on bone.
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Sung WL, Zahab DM, Yao FL, Tam CS. Hybrid gene synthesis: its application to the assembly of DNA sequences encoding the human parathyroid hormones and analogues. Biochem Cell Biol 1986; 64:133-8. [PMID: 3718699 DOI: 10.1139/o86-021] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Bypassing any intermediate steps of purification and gene assembly, several synthetic oligonucleotides constituting a DNA duplex with a small base-mismatching region were phosphorylated, annealed, and ligated directly into a linearized plasmid vector. After transformation in bacteria, the two plasmid strands individually yielded two different plasmids bearing altered versions of the same gene. Via this approach, DNA coding sequences of the human parathyroid hormone and analogues were synthesized and cloned in Escherichia coli.
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Harrison JE, Tam CS, Hitchman AJ, Hitchman A, Hasany SA, Jones G. The relationship between bone apposition rate and vitamin D activity in phosphate-deficient rats. Metabolism 1986; 35:126-9. [PMID: 3484801 DOI: 10.1016/0026-0495(86)90112-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
In rats, phosphorus deficiency (P-) has been shown previously to stimulate the linear bone apposition rate (BAR) and this P- effect is dependent on adequate intake of vitamin D. To investigate further the relative importance of the vitamin D3 metabolites, 1,25(OH)2D3, 24,25(OH)2D3, and 25(OH)D3, in BAR stimulation, we studied, in P- rats, the relationships between BAR and plasma levels of these three vitamin D3 metabolites following vitamin D3 deprivation. Three groups of rats were placed on diets differing only in phosphorus (P) and vitamin D3(D3) content, with one group diet deficient in both P and D3, one diet, P-, D3 replete, and one diet both P and D3 replete. Plasma levels of the three vitamin D3 metabolites, plasma Ca and P, isotopic Ca absorption and BAR measurements were carried out at 1, 3, and 5 weeks after onset of the test diets. In P-, D3 replete rats, both plasma levels of 1,25(OH)2D3 and BAR were increased throughout the 1 to 5 week study period, while 25(OH)D3 and 24,25(OH)2D3 levels were not significantly different from P and D3 replete controls. In P-, D3 restricted rats, BAR was decreased by one week, prior to any reduction in plasma levels of 25(OH)D3 and 24,25(OH)2D3 and while plasma 1,25(OH)2D3 levels were still well above control values. In this P- rat model, the vitamin D dependent BAR stimulation does not appear to be directly related to alterations in the plasma levels of 1,25(OH)2D3, 24,25(OH)2D3, or 25(OH)D3.
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Sung WL, Zahab DM, MacDonald CA, Tam CS. Synthesis of mutant parathyroid hormone genes via site-specific recombination directed by crossover linkers. Gene 1986; 47:261-7. [PMID: 3549455 DOI: 10.1016/0378-1119(86)90069-7] [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: 01/06/2023]
Abstract
A synthetic 'crossover linker' technique has been designed for gene modification. The linker has a restriction end for an initial 'cohesive end' ligation with one terminus of a linearized plasmid, a middle section carrying modified sequence information, and an 'homology-searching' sequence of 20 bp at its other end, that is homologous to a specific region in the opposite terminus of the plasmid. Inside the Escherichia coli transformation host, intramolecular recombination between the homologous ends of the resultant plasmid intermediate completes the integration of the linker. Using different crossover linkers, a human parathyroid hormone gene which had previously been cloned into plasmid pUC8 was converted to mutant coding sequences via specific base substitution, sequence deletion and sequence insertion.
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Abstract
To investigate the effects of fluoride on soft tissue calcification, female weanling rats were fed a nephrocalcinogenic diet and NaF in drinking water over a 4 week period. The diet contained adequate Ca (0.5%) and high phosphorus (1.0%, P). The nephrocalcinosis is attributed to the relatively low dietary Ca/P ratio since addition of Ca to provide a Ca/P ratio of 2.0 prevents kidney calcification. With NaF in drinking water at levels of 1.19 to 4.76 mmol/L kidney calcification was decreased from 127 +/- 24 to 17.3 +/- 1.7 mumol/g wet weight, with no significant differences over this dose range. With the increasing NaF doses, serum F, at 4 weeks, increased from 4.4 +/- 0.8 to 36.5 +/- 6.0 mumol/L compared to untreated F levels of 1.2 +/- 0.1 mumol/L. Bone histology showed no evidence of F stimulation with any of these NaF doses. Previously reported work has shown that, for weanling rats on this diet, greater than 4.8 mumol/L NaF in drinking water is required to produce histological fluorosis within 5 weeks. To inhibit kidney calcification, NaF treatment must be maintained throughout the 4-week study period since calcification occurred if NaF was withheld over either the initial or final 2-week period. These findings indicate a possible therapeutic value of NaF, clinically, in the prevention of soft tissue calcification.
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Harrison JE, Hitchman AJ, Hasany SA, Hitchman A, Tam CS. The effect of diet calcium on fluoride toxicity in growing rats. Can J Physiol Pharmacol 1984; 62:259-65. [PMID: 6722652 DOI: 10.1139/y84-040] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The effect of dietary Ca in response to fluoride (F) treatment was investigated in rats. Rats were maintained on either adequate (0.5%) or high (2.0%) dietary Ca and given for 5 weeks, NaF in drinking water. The minimum NaF levels that inhibited body growth and reduced survival were 300 mg/L with 0.5% diet Ca and 550 mg/L with 2.0% diet Ca. With these toxic F doses, bone histology showed increased formation surfaces and thickened osteoid seams (osteoid index 6-7%). Fluoride doses 30% below toxic levels (200 and 350 mg/L for 0.5 and 2.0% diet Ca, respectively) had no demonstrable effect on bone. Additional diet Ca reduced F absorption from 76 +/- 3 to 47 +/- 3% for 0.5 and 2.0% diet Ca, respectively. Comparable absorbed doses of F produced comparable effects on bone and body growth but, with additional dietary Ca, these effects were observed with 50% lower serum and bone F levels. Variable response to NaF therapy can be produced in rats by alterations in dietary Ca alone. Results indicate that for clinical treatment the NaF dose needs to be adjusted on an individual basis but neither serum nor bone F levels can be used reliably to establish optimal doses.
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Abstract
The effect of Rice H-500 Leydig cell tumor tissue on bone in rats was assessed by morphometric analysis and tetracycline labeling of the lower femoral metaphyses. The rats in which tumor was implanted showed hypercalcemia, increased osteoclastic bone resorption, inhibition of bone formation with reduction in the bone apposition rate, and a loss in trabecular volume compared with the control rats. There was no evidence of tumor metastasis to bone. The results are consistent with the hypothesis that the Leydig cell tumor secretes a humoral factor capable of causing systemic bone resorption.
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Turnbull RS, Heersche JN, Tam CS, Howley TP. Parathyroid hormone stimulates dentin and bone apposition in the thyroparathyroidectomized rat in a dose-dependent fashion. Calcif Tissue Int 1983; 35:586-90. [PMID: 6616323 DOI: 10.1007/bf02405098] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Harrison JE, Hitchman AJ, Jones G, Tam CS, Heersche JN. Plasma vitamin D metabolite levels in phosphorus deficient rats during the development of vitamin D deficient rickets. Metabolism 1982; 31:1121-7. [PMID: 7132739 DOI: 10.1016/0026-0495(82)90162-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Plasma levels of the vitamin D metabolites were related to changes in bone morphology during the development of rickets in rats deprived of phosphorus and vitamin D. Weanling rats were studied at 1, 3, and 5 wk after onset of diets deficient in phosphorus or in both phosphorus and vitamin D. Bone histology and morphometry were carried out and measurements were made of 45Ca and 32P absorption, serum Ca and P, and plasma 25(OH)D3, 24,25(OH)2D3 and 1,25(OH)2D3. After 1 wk of vitamin D restriction, the plasma levels of 25(OH)D3 and 24,25(OH)2D3 were non-detectable (less than 0.5 and less than 0.8 ng/ml). The plasma 1,25(OH)2D3 level was elevated at 1 wk (105.5 pg/ml) and fell to 19 pg/ml by 5 wk. At 1 wk mild rachitic lesions in epiphyseal cartilage were observed despite the elevated 1,25(Oh)D3 level. Serum Ca and P levels and values for 45CA and 32P absorption decreased and the severity of the rickets increased with the fall in plasma levels of 1,25(OH)2D3. In Vitamin D replete, phosphate deficient rats the epiphyseal cartilage was normal throughout the 5 wk study period. Our results provide further evidence that physiological levels of 1,25 (OH)2 D3 will not prevent rickets without adequate plasma concentrations of either 25(OH)D3 or 24,25(OH)2D3.
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Tam CS, Bayley A, Cross EG, Murray TM, Harrison JE. Increased bone apposition in primary hyperparathyroidism: measurements based on short interval tetracycline labeling of bone. Metabolism 1982; 31:759-65. [PMID: 7098847 DOI: 10.1016/0026-0495(82)90072-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Bone biopsies of 23 subjects suffering from primary hyperparathyroidism, which was proven by the demonstration of parathyroid pathology during neck surgery, were studied by morphometric analysis and short interval sequential tetracycline labelling and compared with those of 13 patients without metabolic bone disease. In 19 of these patients, abnormalities were found in the trabecular volume, resorption surface, formation surface, or in various combinations. However, no constant pattern of bone changes was observed. In 4 patients, the bone morphometric parameters were normal. The bone apposition rate, on the other hand, was elevated in all 23 subjects. The rate was re-evaluated in 4 patients 6 wk to 3 mo following successful parathyroid surgery. It fell back within the control range. These findings confirm the observation in experimental animals that parathyroid hormone stimulates bone apposition in vivo and give support to the rationale of using this hormone in the treatment of osteoporosis.
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Tam CS, Heersche JN, Murray TM, Parsons JA. Parathyroid hormone stimulates the bone apposition rate independently of its resorptive action: differential effects of intermittent and continuous administration. Endocrinology 1982; 110:506-12. [PMID: 7056211 DOI: 10.1210/endo-110-2-506] [Citation(s) in RCA: 412] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The deposition of mineralized bone matrix by differentiated osteoblasts was studied in rats in vivo by labeling the bone with three doses of tetracycline given at 48-h intervals. Only bone formation loci bearing all three tetracycline doses were measured, thus eliminating sites where bone formation was not continuous during the labeling period. Using this technique, the effects of intact bovine parathyroid hormone [bPTH-(1-84)] and of a synthetic amino-terminal fragment of human PTH [hPTH-(1-34)] were measured in thyroparathyroidectomized animals. bPTH-(1-84), administered sc, and hPTH-(1-34), administered iv, caused a dose-dependent increase in the bone apposition. Subcutaneous administration of hPTH-(1-34) in doses varying from 2.7-173.0 pmol/rat.day had no effect, probably due to the degradation of the hormone when administered this way. We also compared the effects of bPTH-(1-84) when administered by either daily sc injections or continuous infusion. Continuous infusion of bPTH-(1-84) resulted in an increased apposition rate. Using a morphometric technique, we also found an increase in both formation and resorption surfaces and a net decrease in the trabecular bone volume in this group. Daily injection of the hormone caused an increase in the bone apposition rate, accompanied by an increase in the formation surface without an increase in the resorption surface. This resulted in a net increase in trabecular bone volume. The results thus suggest that the resorptive effects of bPTH-(1-84) can be separated from the effects of the hormone on the apposition rate.
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Tam CS, Jones G, Heersche JN. The effect of vitamin D restriction and repletion on bone apposition in the rat and its dependence on parathyroid hormone. Endocrinology 1981; 109:1448-53. [PMID: 6271531 DOI: 10.1210/endo-109-5-1448] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The regulatory role of vitamin D in bone formation and its interaction with parathyroid hormone (PTH) were analyzed in rats in vivo. The bone apposition rate was determined by measuring the distances between tetracycline lines deposited at 48-h intervals. Vitamin D restriction was associated with a decrease in the bone apposition rate and was paralleled by the expected decrease in serum 25-hydroxyvitamin D3 levels but not by changes in 1,25-dihydroxyvitamin D3 levels. Vitamin D3 repletion restored the apposition rate to normal in parathyroid-intact animals but had no effect in parathyroidectomized animals. Vitamin D repletion of PTH-repleted parathyroidectomized animals restored the bone apposition rate. These results indicate that vitamin D or vitamin D metabolites are required for the expression of the effect of PTH on bone apposition. Conversely, vitamin D repletion only affects the bone formation rate in the presence of PTH, thus suggesting the requirement for PTH-dependent vitamin D metabolism.
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Shike M, Sturtridge WC, Tam CS, Harrison JE, Jones G, Murray TM, Husdan H, Whitwell J, Wilson DR, Jeejeebhoy KN. A possible role of vitamin D in the genesis of parenteral-nutrition-induced metabolic bone disease. Ann Intern Med 1981; 95:560-8. [PMID: 6794407 DOI: 10.7326/0003-4819-95-5-560] [Citation(s) in RCA: 79] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Patients receiving long term parenteral nutrition may develop metabolic bone disease. In all 11 patients studied, histologic studies of bone showed excessive unmineralized bone tissue despite normal plasma 25-hydroxyvitamin D levels. Three patients also had bone pain and fractures and severe urinary loss of calcium and phosphate. Withdrawal of vitamin D from parenteral nutrition solutions was associated with improved histologic findings of bone in all patients, shown by a decrease in osteoid tissue and an increase in tetracycline uptake. In the three patients with symptoms, bone pain subsided, fractures healed, and urinary loss of calcium and phosphate decreased. Thus, vitamin D may be a factor in the genesis of parenteral nutrition-induced metabolic bone disease.
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Tam CS, Wilson DR, Hitchman AJ, Harrison JE. Protective effect on vitamin D2 on bone apposition from the inhibitory action of hydrocortisone in rats. Calcif Tissue Int 1981; 33:167-72. [PMID: 6783273 DOI: 10.1007/bf02409430] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Using the technique of short interval sequential tetracycline labeling, it was documented that the apposition of mineralized bone matrix in adult male Sprague-Dawley rats was inhibited by hydrocortisone. The inhibition occurred as early as six days after the onset of the treatment and was dose dependent over a dose range of 0.62 to 20 mg per kg body weight per day. Vitamin D2 supplements by injection protected bone from this hydrocortisone action. 64 I. U. of vitamin D2 injected daily was able to prevent the inhibition of bone apposition by 20 mg per kg body weight per day of hydrocortisone. The results imply that vitamin D or its metabolites may compete with hydrocortisone in some cellular mechanisms and support the usefulness of vitamin D supplements in the treatment and the prevention of steroid-induced osteoporosis.
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Harrison JE, Hitchman AJ, HItchman A, Hasany SA, McNeill KG, Tam CS. Differences between the effects of phosphate deficiency and vitamin D deficiency on bone metabolism. Metabolism 1980; 29:1225-33. [PMID: 7453566 DOI: 10.1016/0026-0495(80)90149-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
It has been widely believed that phosphate deficiency causes osteomalacia. Based on this belief, the rickets of familial hypophosphatemia has been attributed to phosphate deficiency associated with the hypophosphatemia. The present studies on rats have, however, demonstrated significant differences between the effects of phosphate deficiency on bone metabolism and the characteristic features of rickets. Weanling rats, maintained on a mildly phosphate deficient diet, had hypercalcemia and hypophosphatemia, and impairment of body growth, bone growth, and bone mineralization. The maximum effect was observed at 5 wk; between 5 and 20 wk the rats improved despite persistent hypophosphatemia. Histologically, at 5 wk the bone showed thick unmineralized osteoid seams covering most bone surfaces, but the epiphyseal cartilage was normal. In addition, the excess osteoid readily incorporated tetracycline indicating normal mineralization and, based on a new sequential pulse labeling technique, the linear bone apposition rate (LBA) was significantly (p < 0.001) increased above control values. This increase was observed within the initial 4 days of phosphate (P) deficiency and persisted up to 15 wk. This effect of P deficiency on LBA was dependent on vitamin D activity. At 4 wk, the mean LBA was 0.106 +/- 0.003 (1 SE) in control rats, 0.149 +/- 0.008 microns/hr in P deficient rats, 0.083 +/- 0.004 microns/hr in vitamin D deficient rats and 0.086 +/- 0.006 microns/hr in rats deficient in both P and vitamin D. We have reported a similar increase in LBA with parathyroid hormone activity. With vitamin D deficiency, phosphate deficient rats showed all the characteristic features of rickets; disorganization of epiphyseal cartilage, excessive unmineralized osteoid, and reduced mineralization based on the incorporation of tetracycline. We conclude that the effects of phosphate deficiency on bone metabolism more closely resembles the effects of PTH activity than the characteristic effects of osteomalacia and rickets.
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Shike M, Harrison JE, Sturtridge WC, Tam CS, Bobechko PE, Jones G, Murray TM, Jeejeebhoy KN. Metabolic bone disease in patients receiving long-term total parenteral nutrition. Ann Intern Med 1980; 92:343-50. [PMID: 6766694 DOI: 10.7326/0003-4819-92-3-343] [Citation(s) in RCA: 147] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
We have prospectively investigated calcium and bone metabolism in 16 patients receiving total parenteral nutrition for periods ranging from 7 to 89 months. In 12 patients, bone biopsies at 6 to 73 months after the start of parenteral nutrition showed osteomalacia. Plasma 25-hydroxyvitamin D levels were normal in all patients. Seven persons developed hypercalcemia, and 10 had hypercalciuria with a negative calcium balance. Serum phosphorus was normal and plasma parathyroid hormone level, normal or decreased. Three patients with the severest form of the disease had vitamin D withdrawn from their solutions. Subsequently, urinary calcium decreased, and serum calcium became normal; two persons reverted to a positive calcium balance. Thus, patients receiving total parenteral nutrition may develop metabolic bone disease characterized by osteomalacia, hypercalcemia, hypercalciuria, and a negative calcium balance. This may be caused by both defective mineralization and increased bone resorption induced by vitamin D, its metabolites, or another unrecognized factor.
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Abstract
We have analyzed various aspects of tetracycline labeling technique for the measurement of bone apposition rate in vivo. Our efforts were restricted to those aspects that are frequently questioned when data obtained using this technique are interpreted as representing the rate of bone apposition. Rat bone was labeled in vivo by sequential injections of oxytetracycline at a dose range of 3 to 24 mg/kg body weight and at intervals ranging from 24 to 72 h. The bone apposition rate was calculated by measuring the distance from the first dose of label to the subsequent ones. As these distances are by far too small to be determined accurately by any available micrometer eyepiece, we have used a scanning microscope photometer which allows measurements on slow-forming sites that otherwise would have been considered nongrowing sites. Using these techniques, we have demonstrated that oxytetracycline has no effect on the bone apposition rate when used in the concentrations indicated. In addition, we found that at labeling intervals of 96 h or more, periods of osteoblastic inactivity are likely to be included in measurements at individual sites. The instantaneous apposition rate is thus underestimated at these long time intervals.
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Abstract
The response of bone apposition to some nonphysiologic conditions was investigated. In rabbits, the normal osteogenic rhythm was totally abolished shortly following treatment of hydrocortisone at a dose of 2 mg/kg body weight daily. A new rhythm developed after the treatment was continued for 20 1/2--34 days. The rate of bone apposition was significantly depressed compared to normal data reported previously. In rats receiving one U.S.P. unit of parathyroid extract daily for 14 days, the rate of bone apposition was significantly higher than that in control rats. In both sepcies, the response to an exogenous hormone was identified for all skeletal locations. It was concluded that new bone apposition was a function of activated osteoblasts, and that this function responded only to general body control mechanisms.
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Abstract
The rate of bone apposition was studied by labeling bone with four or five sequential doses of oxytetracycline given at equal intervals of 2 or 4 days in rats and rabbits. The rate was estimated in bone formation sites bearing all the doses. This method has the advantage of assessing the rate of new bone mineralization during the active bone-forming phase only. This index of bone formation was found to be independent of the location of bone samples in the skeleton, and therefore might be under the influence of general body mechanisms only. Preliminary study in the rats indeed yielded results indicating that this bone apposition rate is accelerated by dietary deficiency in calcium.
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Campbell JE, Tam CS, Sheppard RH. "Brown tumor" of hyperparathyroidism induced with anticonvulsant medication. J Can Assoc Radiol 1977; 28:73-6. [PMID: 838762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
A case history is presented of a 50-year-old epileptic receiving massive dose of phenobarbital and small doses of dilantin. Following a minor injury to her forearm a "brown tumor" of hyperparathyroidism and osteomalacia, both of which responded to vitamin D.A review of the literature is given; this is the second case reported which documents hyperparathyroidism under such circumstances, and the first to show radiographs of such changes. Radiologists should be aware of the possibility of these changes in patients on long-term anticonvulsants.
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Swinson DR, Tam CS, Reed R, Hoffman D, Little AH, Cruickshank B. Bone growth kinetics IV: a preliminary investigation on a biorhythm in human osteogenesis. J Pathol 1975; 116:13-6. [PMID: 1159573 DOI: 10.1002/path.1711160103] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Multiple doses of oxytetracycline were administered at regular but different intervals to groups of patients undergoin orthopaedic surgery. It was found that doses of the drug were incorporated at bone growth sites most frequently if the intervals between those doses were 3 or 6 days. This suggests a biorhythm in human bone growth with a periodicity of 3 days: this biorhythm may be altered by hormones or drugs.
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Harrison JE, Hitchman AJ, Tam CS. Intestinal calcium-binding protein in animals fed normal and rachitogenic diets: I. Rat studies. Can J Physiol Pharmacol 1975; 53:137-43. [PMID: 1139439 DOI: 10.1139/y75-019] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Measurements were made of duodenal calcium-binding protein (CaBP) on rats during development of rickets and, subsequently, following vitamin-D2 treatment. Results showed a poor inverse correlation between duodenal CaBP and rickets. In rats fed a phosphate-deficient rachitogenic diet, duodenal CaBP concentration finally fell below detectable limits, but CaBP was still readily measurable 2 weeks after rickets was clearly established. Following a massive dose of vitamin D2 (50 000 I.U.) to rachitic animals, CaBP was formed. However, a small dose of vitamin D2 (500 I.U. daily for 4 days) was insufficient to demonstrate CaBP synthesis than vitamin-D treatment alone. The rachitogenic diet supplemented with phosphate, which caused osteoporosis but not rickets, inhibited CaBP synthesis. The results suggest that nutritional deficiencies from the rachitogenic diet, in addition to vitamin-D deficiency, inhibited CaBP synthesis.
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