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Raygada M, John L, Liu A, Schultz J, Thomas BJ, Bernstein D, Miettinen M, Raffeld M, Xi L, Tyagi M, Aldape K, Glod J, Reilly KM, Widemann BC, Wedekind MF. Germline findings in cancer predisposing genes from a small cohort of chordoma patients. J Cancer Res Clin Oncol 2024; 150:227. [PMID: 38700789 PMCID: PMC11068663 DOI: 10.1007/s00432-024-05706-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Accepted: 03/15/2024] [Indexed: 05/06/2024]
Abstract
INTRODUCTION Chordoma is a rare slow-growing tumor that occurs along the length of the spinal axis and arises from primitive notochordal remnants (Stepanek et al., Am J Med Genet 75:335-336, 1998). Most chordomas are sporadic, but a small percentage of cases are due to hereditary cancer syndromes (HCS) such as tuberous sclerosis 1 and 2 (TSC1/2), or constitutional variants in the gene encoding brachyury T (TBXT) (Pillay et al., Nat Genet 44:1185-1187, 2012; Yang et al., Nat Genet 41:1176-1178, 2009). PURPOSE The genetic susceptibility of these tumors is not well understood; there are only a small number of studies that have performed germline genetic testing in this population. METHODS We performed germline genetic in chordoma patients using genomic DNA extracted by blood or saliva. CONCLUSION We report here a chordoma cohort of 24 families with newly found germline genetic mutations in cancer predisposing genes. We discuss implications for genetic counseling, clinical management, and universal germline genetic testing for cancer patients with solid tumors.
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Affiliation(s)
- Margarita Raygada
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA.
- NIH Clinical Center (Building 10), 10 Center Drive, Room 1-3750, Bethesda, MD, 20892, USA.
| | - Liny John
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - Anne Liu
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - Julianne Schultz
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - B J Thomas
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - Donna Bernstein
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - Markku Miettinen
- Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - Mark Raffeld
- Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - Liqiang Xi
- Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - Manoj Tyagi
- Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - Kenneth Aldape
- Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - John Glod
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - Karlyne M Reilly
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - Brigitte C Widemann
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - Mary Frances Wedekind
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA.
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Ahmed S, Wedekind MF, Del Rivero J, Raygada M, Lockridge R, Glod JW, Flowers C, Thomas BJ, Bernstein DB, Kapustina OB, Jain A, Miettinen M, Raffeld M, Xi L, Tyagi M, Kim J, Aldape K, Malayeri AA, Kaplan RN, Allen T, Vivelo CA, Sandler AB, Widemann BC, Reilly KM. Longitudinal Natural History Study of Children and Adults with Rare Solid Tumors: Initial Results for First 200 Participants. Cancer Res Commun 2023; 3:2468-2482. [PMID: 37966258 PMCID: PMC10699159 DOI: 10.1158/2767-9764.crc-23-0247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 11/03/2023] [Accepted: 11/07/2023] [Indexed: 11/16/2023]
Abstract
Understanding of tumor biology and identification of effective therapies is lacking for many rare tumors. My Pediatric and Adult Rare Tumor (MyPART) network was established to engage patients, advocates, and researchers and conduct a comprehensive longitudinal Natural History Study of Rare Solid Tumors. Through remote or in-person enrollment at the NIH Clinical Center, participants with rare solid tumors ≥4 weeks old complete standardized medical and family history forms, patient reported outcomes, and provide tumor, blood and/or saliva samples. Medical records are extracted for clinical status and treatment history, and tumors undergo genomic analysis. A total of 200 participants (65% female, 35% male, median age at diagnosis 43 years, range = 2-77) enrolled from 46 U.S. states and nine other countries (46% remote, 55% in-person). Frequent diagnoses were neuroendocrine neoplasms (NEN), adrenocortical carcinomas (ACC), medullary thyroid carcinomas (MTC), succinate dehydrogenase (SDH)-deficient gastrointestinal stromal tumors (sdGIST), and chordomas. At enrollment, median years since diagnosis was 3.5 (range = 0-36.6), 63% participants had metastatic disease and 20% had no evidence of disease. Pathogenic germline and tumor mutations included SDHA/B/C (sdGIST), RET (MTC), TP53 and CTNNB1 (ACC), MEN1 (NEN), and SMARCB1 (poorly-differentiated chordoma). Clinically significant anxiety was observed in 20%-35% of adults. Enrollment of participants and comprehensive data collection were feasible. Remote enrollment was critical during the COVID-19 pandemic. Over 30 patients were enrolled with ACC, NEN, and sdGIST, allowing for clinical/genomic analyses across tumors. Longitudinal follow-up and expansion of cohorts are ongoing to advance understanding of disease course and establish external controls for interventional trials. SIGNIFICANCE This study demonstrates that comprehensive, tumor-agnostic data and biospecimen collection is feasible to characterize different rare tumors, and speed progress in research. The findings will be foundational to developing external controls groups for single-arm interventional trials, where randomized control trials cannot be conducted because of small patient populations.
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Affiliation(s)
- Shadin Ahmed
- Pediatric Oncology Branch, Center for Cancer Research, NCI, Bethesda, Maryland
| | | | - Jaydira Del Rivero
- Developmental Therapeutics Branch, Center for Cancer Research, NCI, Bethesda, Maryland
| | - Margarita Raygada
- Pediatric Oncology Branch, Center for Cancer Research, NCI, Bethesda, Maryland
| | - Robin Lockridge
- Clinical Research Directorate (CRD), Frederick National Laboratory for Cancer Research, Frederick, Maryland
| | - John W. Glod
- Pediatric Oncology Branch, Center for Cancer Research, NCI, Bethesda, Maryland
| | - Crystal Flowers
- Pediatric Oncology Branch, Center for Cancer Research, NCI, Bethesda, Maryland
| | - BJ Thomas
- Pediatric Oncology Branch, Center for Cancer Research, NCI, Bethesda, Maryland
| | - Donna B. Bernstein
- Pediatric Oncology Branch, Center for Cancer Research, NCI, Bethesda, Maryland
| | - Oxana B. Kapustina
- Pediatric Oncology Branch, Center for Cancer Research, NCI, Bethesda, Maryland
| | - Ashish Jain
- Pediatric Oncology Branch, Center for Cancer Research, NCI, Bethesda, Maryland
- Research Computing, Department of Information Technology, Boston Children's Hospital, Boston, Massachusetts
| | - Markku Miettinen
- Laboratory of Pathology, Center for Cancer Research, NCI, Bethesda, Maryland
| | - Mark Raffeld
- Laboratory of Pathology, Center for Cancer Research, NCI, Bethesda, Maryland
| | - Liqiang Xi
- Laboratory of Pathology, Center for Cancer Research, NCI, Bethesda, Maryland
| | - Manoj Tyagi
- Laboratory of Pathology, Center for Cancer Research, NCI, Bethesda, Maryland
| | - Jung Kim
- Laboratory of Pathology, Center for Cancer Research, NCI, Bethesda, Maryland
| | - Kenneth Aldape
- Laboratory of Pathology, Center for Cancer Research, NCI, Bethesda, Maryland
| | - Ashkan A. Malayeri
- Department of Radiology and Imaging Sciences, Clinical Center, NIH, Bethesda, Maryland
| | - Rosandra N. Kaplan
- Pediatric Oncology Branch, Center for Cancer Research, NCI, Bethesda, Maryland
| | - Taryn Allen
- Pediatric Oncology Branch, Center for Cancer Research, NCI, Bethesda, Maryland
- Clinical Research Directorate (CRD), Frederick National Laboratory for Cancer Research, Frederick, Maryland
| | - Christina A. Vivelo
- Pediatric Oncology Branch, Center for Cancer Research, NCI, Bethesda, Maryland
- Kelly Government Solutions, Bethesda, Maryland
| | - Abby B. Sandler
- Pediatric Oncology Branch, Center for Cancer Research, NCI, Bethesda, Maryland
| | | | - Karlyne M. Reilly
- Pediatric Oncology Branch, Center for Cancer Research, NCI, Bethesda, Maryland
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Shetty I, Fuller S, Raygada M, Merino MJ, Thomas BJ, Widemann BC, Reilly KM, Pacak K, Del Rivero J. Adrenocortical carcinoma masquerading as pheochromocytoma: a histopathologic dilemma. Endocrinol Diabetes Metab Case Rep 2020; 2020:EDM190147. [PMID: 31917677 PMCID: PMC6993251 DOI: 10.1530/edm-19-0147] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 12/05/2019] [Indexed: 11/25/2022] Open
Abstract
SUMMARY Adrenocortical carcinoma (ACC) is an aggressive cancer that originates in the cortex of the adrenal gland and generally has a poor prognosis. ACC is rare but can be more commonly seen in those with cancer predisposition syndromes (e.g. Li-Fraumeni and Lynch Syndrome). The diagnosis of ACC is sometimes uncertain and it requires the use of precise molecular pathology; the differential diagnosis includes pheochromocytoma, adrenal adenoma, renal carcinoma, or hepatocellular carcinoma. We describe a case of a 57-year-old woman with Lynch Syndrome and metastatic ACC who was initially diagnosed as having pheochromocytoma. The tumor was first identified at 51 years of age by ultrasound followed by a CT scan. She underwent a left adrenalectomy, and the histopathology identified pheochromocytoma. Two years later, she had tumor recurrence with imaging studies showing multiple lung nodules. Following a wedge resection by video-assisted thoracoscopic surgery (VATS), histopathology was read as metastatic pheochromocytoma at one institution and metastatic ACC at another institution. She later presented to the National Institutes of Health (NIH) where the diagnosis of ACC was confirmed. Following her ACC diagnosis, she was treated with mitotane and pembrolizumab which were stopped due to side effects and progression of disease. She is currently receiving etoposide, doxorubicin, and cisplatin (EDP). This case highlights the importance of using a multi-disciplinary approach in patient care. Thorough evaluation of the tumor's pathology and analysis of the patient's genetic profile are necessary to obtain the correct diagnosis for the patient and can significantly influence the course of treatment. LEARNING POINTS Making the diagnosis of ACC can be difficult as the differential diagnosis includes pheochromocytoma, adrenal adenoma, renal carcinoma, or hepatocellular carcinoma. Patients with Lynch Syndrome should undergo surveillance for ACC as there is evidence of an association between Lynch Syndrome and ACC. Conducting a complete tumor immunoprofile and obtaining a second opinion is very important in cases of suspected ACC in order to confirm the proper diagnosis. A multi-disciplinary approach including genetic testing and a thorough evaluation of the tumor's pathology is imperative to ensuring that the patient receives an accurate diagnosis and the appropriate treatment.
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Affiliation(s)
- Impana Shetty
- Pediatric Oncology Branch, Rare Tumor Initiative, Center for Cancer Research, National Cancer Institute, Clinical Center
| | - Sarah Fuller
- Pediatric Oncology Branch, Rare Tumor Initiative, Center for Cancer Research, National Cancer Institute, Clinical Center
| | - Margarita Raygada
- Pediatric Oncology Branch, Rare Tumor Initiative, Center for Cancer Research, National Cancer Institute, Clinical Center
| | - Maria J Merino
- Laboratory of Pathology, National Cancer Institute, Clinical Center
| | - B J Thomas
- Pediatric Oncology Branch, Rare Tumor Initiative, Center for Cancer Research, National Cancer Institute, Clinical Center
| | - Brigitte C Widemann
- Pediatric Oncology Branch, Rare Tumor Initiative, Center for Cancer Research, National Cancer Institute, Clinical Center
| | - Karlyne M Reilly
- Pediatric Oncology Branch, Rare Tumor Initiative, Center for Cancer Research, National Cancer Institute, Clinical Center
| | - Karel Pacak
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA
| | - Jaydira Del Rivero
- Pediatric Oncology Branch, Rare Tumor Initiative, Center for Cancer Research, National Cancer Institute, Clinical Center
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Thomas BJ, Fuller S, Ilanchezhian M, Allen D, Allen T, Weiner L, Wisch L, Sherri D, Gillespie A, Raygada M, Arnaldez F, Reilly K, Glod J, Widemann B, Del Rivero J. SUN-341 A Natural History Study for Rare Tumors: An Avenue for Discovering and Understanding Endocrine Cancers. J Endocr Soc 2019. [PMCID: PMC6552796 DOI: 10.1210/js.2019-sun-341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Introduction: Endocrine malignancies, as well as all pediatric cancers, are considered rare tumors, defined as <200,000 affected at any given time in US or <40,000 new cases per year. Rare tumors may present as part of a hereditary cancer syndrome, (e.g multipe endocrine neoplasia type 1) or isolated. These tumors have been traditionally understudied and lack descriptive epidemiology, comprehensive genomic profiles, and phenotypic characterization. In an effort to understand the natural history of these rare cancers, the Pediatric Oncology Branch (POB) of the National Cancer Institute (NCI) has undertaken a rare tumor initiative. Methods: A prospective study has been developed at the NCI to comprehensively and longitudinally evaluate the natural history of patients with rare solid tumors or tumor predisposition syndromes. The goals of this study are to 1) estimate and define the clinical spectrum of rare cancers, 2) evaluate and follow biological relatives of patients with rare tumors or carriers of germline genetic variants that predispose to development of rare tumors, and 3) develop a better understanding of these diseases in an effort to a) develop novel therapeutic interventions, b) preventive/screening guidelines, c) endpoints for future clinical trials, and d) identify relevant patient reported outcomes that can improve our understanding of patients’ psychosocial and functional needs. Results: The NCI Natural History Study of Rare Solid Tumor (NCT03739827) has recently opened. This expands on previous work within the NCI in rare tumors including a neurofibromatosis natural history study (NCT00924196) and a multiple endocrine neoplasia type 2 study (NCT01660984). The MEN2 natural history study has enrolled 59 total subjects including 46 patients with MEN2B and 13 with MEN2A. This work has led to a better understanding of the MEN2B phenotype and contributed to the development of vandetanib (NCT00514046) in pediatric patients. We have explored the psychosocial impact of living with MTC in both pediatric and adult patients. We are developing a sub-protocol on tumors with Krebs cycle abnormalities including succinate dehydrogenase deficient pheochromocytoma/paraganglioma and gastrointestinal stromal tumor. Discussion: Natural history studies track the course of the disease over time. They can identify demographic, genetic, environmental, and other variables that correlate with disease and outcomes, either in the absence or presence of experimental therapy or standard care. Comprehensive studies are a pillar of epidemiologic research on rare conditions and can help optimize clinical care and inform the development of novel treatments. They can also provide key information about how rare diseases develop and progress, leading to development of disease models that help make drug development more efficient and advancing the understanding of rare endocrine tumors. Unless otherwise noted, all abstracts presented at ENDO are embargoed until the date and time of presentation. For oral presentations, the abstracts are embargoed until the session begins. Abstracts presented at a news conference are embargoed until the date and time of the news conference. The Endocrine Society reserves the right to lift the embargo on specific abstracts that are selected for promotion prior to or during ENDO.
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Affiliation(s)
- BJ Thomas
- National Cancer Institute/NIH, Bethesda, MD, United States
| | - Sarah Fuller
- National Cancer Institute/NIH, Bethesda, MD, United States
| | | | - Deborah Allen
- National Cancer Institute/NIH, Bethesda, MD, United States
| | - Taryn Allen
- National Cancer Institute/NIH, Bethesda, MD, United States
| | - Lori Weiner
- National Cancer Institute/NIH, Bethesda, MD, United States
| | - Laura Wisch
- National Cancer Institute/NIH, Bethesda, MD, United States
| | | | - Andy Gillespie
- National Cancer Institute/NIH, Bethesda, MD, United States
| | | | | | - Karlyne Reilly
- National Cancer Institute/NIH, Bethesda, MD, United States
| | - John Glod
- Pediatric Oncology Branch, NCI, NIH, National Cancer Institute/NIH, Bethesda, MD, United States
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Abstract
Seventy-eight men with a history of chronic urethritis were referred for investigation. Of 52 men diagnosed as having persistent or recurrent non-gonococcal urethritis (NGU) at the time of referral, 11 (21%) were infected with Mycoplasma genitalium and three with Chlamydia trachomatis. Men who were M. genitalium-positive had not previously received less antibiotic, in terms of treatment duration, than those who were M. genitalium-negative, suggesting a possible resistance to the antibiotics given. In the current investigation, of 11 M. genitalium-positive men with persistent or recurrent NGU who were treated for four to six weeks with erythromycin, 500mg four times daily, nine (82%) responded clinically and microbiologically, but later six relapsed without M. genitalium being detected. The results of observing and investigating a patient for about one year, the only one to have concurrent chlamydial and mycoplasmal infections, is presented, a feature being the intermittent persistence of the mycoplasma.
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Affiliation(s)
- D Taylor-Robinson
- Division of Medicine, Imperial College London, St Mary's Hospital, London W2 1NY, UK
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Finkelstein JS, Lee H, Burnett-Bowie SAM, Pallais JC, Yu EW, Borges LF, Jones BF, Barry CV, Wulczyn KE, Thomas BJ, Leder BZ. Gonadal steroids and body composition, strength, and sexual function in men. N Engl J Med 2013; 369:1011-22. [PMID: 24024838 PMCID: PMC4142768 DOI: 10.1056/nejmoa1206168] [Citation(s) in RCA: 471] [Impact Index Per Article: 42.8] [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: 12/27/2022]
Abstract
BACKGROUND Current approaches to diagnosing testosterone deficiency do not consider the physiological consequences of various testosterone levels or whether deficiencies of testosterone, estradiol, or both account for clinical manifestations. METHODS We provided 198 healthy men 20 to 50 years of age with goserelin acetate (to suppress endogenous testosterone and estradiol) and randomly assigned them to receive a placebo gel or 1.25 g, 2.5 g, 5 g, or 10 g of testosterone gel daily for 16 weeks. Another 202 healthy men received goserelin acetate, placebo gel or testosterone gel, and anastrozole (to suppress the conversion of testosterone to estradiol). Changes in the percentage of body fat and in lean mass were the primary outcomes. Subcutaneous- and intraabdominal-fat areas, thigh-muscle area and strength, and sexual function were also assessed. RESULTS The percentage of body fat increased in groups receiving placebo or 1.25 g or 2.5 g of testosterone daily without anastrozole (mean testosterone level, 44±13 ng per deciliter, 191±78 ng per deciliter, and 337±173 ng per deciliter, respectively). Lean mass and thigh-muscle area decreased in men receiving placebo and in those receiving 1.25 g of testosterone daily without anastrozole. Leg-press strength fell only with placebo administration. In general, sexual desire declined as the testosterone dose was reduced. CONCLUSIONS The amount of testosterone required to maintain lean mass, fat mass, strength, and sexual function varied widely in men. Androgen deficiency accounted for decreases in lean mass, muscle size, and strength; estrogen deficiency primarily accounted for increases in body fat; and both contributed to the decline in sexual function. Our findings support changes in the approach to evaluation and management of hypogonadism in men. (Funded by the National Institutes of Health and others; ClinicalTrials.gov number, NCT00114114.).
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Affiliation(s)
- Joel S Finkelstein
- Endocrine Unit, Department of Medicine, Massachusetts General Hospital, Boston, MA 02114, USA.
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7
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Bredella MA, Lin E, Gerweck AV, Landa MG, Thomas BJ, Torriani M, Bouxsein ML, Miller KK. Determinants of bone microarchitecture and mechanical properties in obese men. J Clin Endocrinol Metab 2012; 97:4115-22. [PMID: 22933540 PMCID: PMC3485587 DOI: 10.1210/jc.2012-2246] [Citation(s) in RCA: 103] [Impact Index Per Article: 8.6] [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: 02/02/2023]
Abstract
CONTEXT Recent studies have suggested that obesity in men is associated with increased fracture risk. Obesity in men is also associated with dysregulation of the GH/IGF-I and gonadal steroid axes, important regulators of bone homeostasis. OBJECTIVE The aim of the study was to investigate body composition and endocrine determinants of bone microarchitecture and mechanical properties in obese men. DESIGN AND SETTING We conducted a cross-sectional study at a clinical research center. PARTICIPANTS Thirty-five obese men (mean age, 33.8 ± 6.4 yr; mean body mass index, 36.5 ± 5.8 kg/m(2)) participated in the study. OUTCOME MEASURES Distal radius microarchitecture and mechanical properties were measured by three-dimensional high-resolution peripheral quantitative computed tomography and microfinite element analysis; body composition by computed tomography; bone marrow fat by proton magnetic resonance spectroscopy; total and free estradiol and testosterone; IGF-I; peak glucagon-stimulated GH; 25-hydroxyvitamin D. RESULTS Men with high visceral adipose tissue (VAT) had impaired mechanical properties compared to men with low VAT (P < 0.05), despite comparable body mass index. VAT was inversely associated and thigh muscle was positively associated with mechanical properties (P < 0.05). Bone marrow fat was inversely associated with cortical parameters (P ≤ 0.02). Free estradiol was positively associated with total density (P = 0.05). Free testosterone was positively associated with trabecular thickness and inversely with trabecular number (P ≤ 0.05). Peak stimulated GH was positively associated with trabecular thickness, as was IGF-I with cortical area (P ≤ 0.04). CONCLUSION VAT and bone marrow fat are negative predictors and muscle mass is a positive predictor of microarchitecture and mechanical properties in obese men. Testosterone, estradiol, and GH are positive determinants of trabecular microarchitecture, and IGF-I is a positive determinant of cortical microarchitecture. This supports the notion that VAT is detrimental to bone and that decreased GH and testosterone, characteristic of male obesity, may exert deleterious effects on microarchitecture, whereas higher estradiol may be protective.
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Affiliation(s)
- Miriam A Bredella
- Massachusetts General Hospital, Yawkey 6E, 55 Fruit Street, Boston, Massachusetts 02114, USA.
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8
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Fazeli PK, Bredella MA, Freedman L, Thomas BJ, Breggia A, Meenaghan E, Rosen CJ, Klibanski A. Marrow fat and preadipocyte factor-1 levels decrease with recovery in women with anorexia nervosa. J Bone Miner Res 2012; 27:1864-71. [PMID: 22508185 PMCID: PMC3415584 DOI: 10.1002/jbmr.1640] [Citation(s) in RCA: 89] [Impact Index Per Article: 7.4] [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: 01/22/2023]
Abstract
Women with anorexia nervosa (AN) have elevated marrow fat mass despite low visceral and subcutaneous fat depots, which is inversely associated with bone mineral density (BMD). Whether marrow fat mass remains persistently elevated or decreases with recovery from AN is currently unknown. In this study, we investigated changes in marrow fat in women who have recovered from AN (AN-R). We also studied the relationship between preadipocyte factor (Pref)-1-a member of the EGF-like family of proteins and regulator of adipocyte and osteoblast differentiation-and fat depots and BMD in AN-R compared with women with AN and healthy controls (HC). We studied 29 women: 14 with active or recovered AN (30.7 + 2.2 years [mean ± SEM]) and 15 normal-weight controls (27.8 ± 1.2 years). We measured marrow adipose tissue (MAT) of the L4 vertebra and femur by (1) H-magnetic resonance spectroscopy; BMD of the spine, hip, and total body by DXA; and serum Pref-1 and leptin levels. We found that MAT of the L4 vertebra was significantly lower in AN-R compared with AN (p = 0.03) and was comparable to levels in HC. Pref-1 levels were also significantly lower in AN-R compared with AN (p = 0.02) and comparable to levels in healthy controls. Although Pref-1 was positively associated with MAT of the L4 vertebra in AN (R = 0.94; p = 0.002), we found that it was inversely associated with MAT of the L4 vertebra in HC (R = -0.71; p = 0.004). Therefore, we have shown that MAT and Pref-1 levels decrease with recovery from AN. Our data suggest that Pref-1 may have differential effects in states of nutritional deprivation compared with nutritional sufficiency.
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Affiliation(s)
- Pouneh K Fazeli
- Neuroendocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA.
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Torriani M, Townsend E, Thomas BJ, Bredella MA, Ghomi RH, Tseng BS. Lower leg muscle involvement in Duchenne muscular dystrophy: an MR imaging and spectroscopy study. Skeletal Radiol 2012; 41:437-45. [PMID: 21800026 PMCID: PMC3713639 DOI: 10.1007/s00256-011-1240-1] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2011] [Revised: 07/12/2011] [Accepted: 07/15/2011] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To describe the involvement of lower leg muscles in boys with Duchenne muscular dystrophy (DMD) by using MR imaging (MRI) and spectroscopy (MRS) correlated to indices of functional status. SUBJECTS AND METHODS Nine boys with DMD (mean age, 11 years) and eight healthy age- and BMI-matched boys (mean age, 13 years) prospectively underwent lower leg MRI, 1H-MRS of tibialis anterior (TA) and soleus (SOL) for lipid fraction measures, and 31P-MRS for pH and high-energy phosphate measures. DMD subjects were evaluated using the Vignos lower extremity functional rating, and tests including 6 min walk test (6MWT) and 10 m walk. RESULTS DMD subjects had highest fatty infiltration scores in peroneal muscles, followed by medial gastrocnemius and soleus. Compared to controls, DMD boys showed higher intramuscular fat (P = 0.04), lipid fractions of TA and SOL (P = 0.02 and 0.003, respectively), pH of anterior compartment (P = 0.0003), and lower phosphocreatine/inorganic phosphorus ratio of posterior compartment (P = 0.02). The Vignos rating correlated with TA (r = 0.79, P = 0.01) and SOL (r = 0.71, P = 0.03) lipid fractions. The 6MWT correlated with fatty infiltration scores of SOL (r = -0.76, P = 0.046), medial (r = -0.80, P = 0.03) and lateral (r = -0.84, P = 0.02) gastrocnemius, intramuscular fat (r = -0.80, P = 0.03), and SOL lipid fraction (r = -0.89, P = 0.007). Time to walk 10 m correlated with anterior compartment pH (r = 0.78, P = 0.04). CONCLUSION Lower leg muscles of boys with DMD show a distinct involvement pattern and increased adiposity that correlates with functional status. Lower leg MRI and 1H-MRS studies may help to noninvasively demonstrate the severity of muscle involvement.
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Affiliation(s)
- Martin Torriani
- Division of Musculoskeletal Imaging and Intervention, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA.
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10
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Bredella MA, Lin E, Brick DJ, Gerweck AV, Harrington LM, Torriani M, Thomas BJ, Schoenfeld DA, Breggia A, Rosen CJ, Hemphill LC, Wu Z, Rifai N, Utz AL, Miller KK. Effects of GH in women with abdominal adiposity: a 6-month randomized, double-blind, placebo-controlled trial. Eur J Endocrinol 2012; 166:601-11. [PMID: 22275471 PMCID: PMC3651853 DOI: 10.1530/eje-11-1068] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE Abdominal adiposity is associated with increased cardiovascular risk and decreased GH secretion. The objective of our study was to determine the effects of GH on body composition and cardiovascular risk markers in abdominally obese women. MATERIALS AND METHODS In this randomized, double-blind, placebo-controlled study, 79 obese premenopausal women received GH vs placebo for 6 months. Primary endpoints were i) total abdominal (total abdominal adipose tissue, TAT) fat by computed tomography (CT) (body composition) and ii) high-sensitivity C-reactive protein (hsCRP) (cardiovascular risk marker). Body composition was assessed by CT, dual-energy X-ray absorptiometry, and proton MR spectroscopy. Serum cardiovascular risk markers, carotid intima-media thickness, and endothelial function were measured. RESULTS Mean 6-month GH dose was 1.7±0.1 mg/day, resulting in a mean IGF1 SDS increase from -1.7±0.08 to -0.1±0.3 in the GH group. GH administration decreased TAT and hsCRP compared with placebo. In addition, it increased thigh muscle mass and lean body mass and decreased subcutaneous abdominal and trunk fat, tissue plasminogen activator, apoB, and apoB/low-density lipoprotein compared with placebo. Visceral adipose tissue (VAT) decreased and intramyocellular lipid increased within the GH group. Six-month change in IGF1 levels was negatively associated with 6-month decrease in TAT and VAT. One subject had a 2 h glucose >200 mg/ml at 3 months; four subjects, three of whom were randomized to GH, had 2 h glucose levels >200 mg/ml at the end of the study. CONCLUSION GH administration in abdominally obese premenopausal women exerts beneficial effects on body composition and cardiovascular risk markers but is associated with a decrease in glucose tolerance in a minority of women.
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Affiliation(s)
- Miriam A Bredella
- Department of Radiology, Neuroendocrine Unit Biostatistics Center, Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, MA 02114, USA.
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11
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Yu EW, Thomas BJ, Brown JK, Finkelstein JS. Simulated increases in body fat and errors in bone mineral density measurements by DXA and QCT. J Bone Miner Res 2012; 27:119-24. [PMID: 21915902 PMCID: PMC3864640 DOI: 10.1002/jbmr.506] [Citation(s) in RCA: 186] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Revised: 08/25/2011] [Accepted: 08/29/2011] [Indexed: 11/05/2022]
Abstract
Major alterations in body composition, such as with obesity and weight loss, have complex effects on the measurement of bone mineral density (BMD) by dual-energy X-ray absorptiometry (DXA). The effects of altered body fat on quantitative computed tomography (QCT) measurements are unknown. We scanned a spine phantom by DXA and QCT before and after surrounding with sequential fat layers (up to 12 kg). In addition, we measured lumbar spine and proximal femur BMD by DXA and trabecular spine BMD by QCT in 13 adult volunteers before and after a simulated 7.5 kg increase in body fat. With the spine phantom, DXA BMD increased linearly with sequential fat layering at the normal (p < 0.01) and osteopenic (p < 0.01) levels, but QCT BMD did not change significantly. In humans, fat layering significantly reduced DXA spine BMD values (mean ± SD: -2.2 ± 3.7%, p = 0.05) and increased the variability of measurements. In contrast, fat layering increased QCT spine BMD in humans (mean ± SD: 1.5 ± 2.5%, p = 0.05). Fat layering did not change mean DXA BMD of the femoral neck or total hip in humans significantly, but measurements became less precise. Associations between baseline and fat-simulation scans were stronger for QCT of the spine (r(2)= 0.97) than for DXA of the spine (r(2)= 0.87), total hip (r(2) = 0.80), or femoral neck (r(2)= 0.75). Bland-Altman plots revealed that fat-associated errors were greater for DXA spine and hip BMD than for QCT trabecular spine BMD. Fat layering introduces error and decreases the reproducibility of DXA spine and hip BMD measurements in human volunteers. Although overlying fat also affects QCT BMD measurements, the error is smaller and more uniform than with DXA BMD. Caution must be used when interpreting BMD changes in humans whose body composition is changing.
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Affiliation(s)
- Elaine W Yu
- Endocrine Unit, Massachusetts General Hospital, Boston, MA 02114, USA.
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12
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Ghomi RH, Bredella MA, Thomas BJ, Miller KK, Torriani M. Modular MR-compatible lower leg exercise device for whole-body scanners. Skeletal Radiol 2011; 40:1349-54. [PMID: 21271342 PMCID: PMC3667703 DOI: 10.1007/s00256-011-1098-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2010] [Revised: 01/04/2011] [Accepted: 01/06/2011] [Indexed: 02/02/2023]
Abstract
PURPOSE To develop a modular MR-compatible lower leg exercise device for muscle testing using a clinical 3 T MR scanner. MATERIALS AND METHODS An exercise device to provide isotonic resistance to plantar- or dorsiflexion was constructed from nonferrous materials and designed for easy setup and use in a clinical environment. Validation tests were performed during dynamic MR acquisitions. For this purpose, the device was tested on the posterior lower leg musculature of five subjects during 3 min of exercise at 30% of maximum voluntary plantarflexion during 31-phosphorus MR spectroscopy ((31)P-MRS). Measures of muscle phosphocreatine (PCr), inorganic phosphate (Pi), and pH were obtained before, during, and after the exercise protocol. RESULTS At the end of exercise regimen, muscle PCr showed a 28% decrease from resting levels (to 21.8 ± 3.9 from 30.4 ± 3.0 mM) and the average PCr recovery rate was 35.3 ± 8.3 s. Muscle Pi concentrations increased 123% (to 14.6 ± 4.7 from 6.5 ± 3.3 mM) and pH decreased 1.5% (to 7.06 ± 0.14 from 7.17 ± 0.07) from resting levels. CONCLUSION The described MR-compatible lower leg exercise was an effective tool for data acquisition during dynamic MR acquisitions of the calf muscles. The modular design allows for adaptation to other whole-body MR scanners and incorporation of custom-built mechanical or electronic interfaces and can be used for any MR protocol requiring dynamic evaluation of calf muscles.
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Affiliation(s)
- Reza Hosseini Ghomi
- Musculoskeletal Imaging and Intervention, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, YAW 6048, Boston, MA 02114, USA
| | - Miriam A. Bredella
- Musculoskeletal Imaging and Intervention, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, YAW 6048, Boston, MA 02114, USA
| | - Bijoy J. Thomas
- Musculoskeletal Imaging and Intervention, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, YAW 6048, Boston, MA 02114, USA
| | - Karen K. Miller
- Neuroendocrine Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Martin Torriani
- Musculoskeletal Imaging and Intervention, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, YAW 6048, Boston, MA 02114, USA
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Thomas BJ. Education and training of medical physicists in South East Asia: accomplishments and challenges. Biomed Imaging Interv J 2011; 7:e23. [PMID: 22279500 PMCID: PMC3265195 DOI: 10.2349/biij.7.3.e23] [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] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Accepted: 08/10/2011] [Indexed: 11/24/2022] Open
Abstract
John Cameron has made significant contributions to the field of Medical Physics. His contributions encompassed research and development, technical developments and education. He had a particular interest in the education of medical physicists in developing countries. Structured clinical training is also an essential component of the professional development of a medical physicist. This paper considers aspects of the clinical training and education of medical physicists in South-East Asia and the challenges facing the profession in the region if it is to keep pace with the rapid increase in the amount and technical complexity of medical physics infrastructure in the region.
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Affiliation(s)
- B J Thomas
- Faculty of Science and Technology, Queensland University of Technology, Brisbane Queensland, Australia.
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Canapari CA, Hoppin AG, Kinane TB, Thomas BJ, Torriani M, Katz ES. Relationship between sleep apnea, fat distribution, and insulin resistance in obese children. J Clin Sleep Med 2011; 7:268-73. [PMID: 21677896 PMCID: PMC3113965 DOI: 10.5664/jcsm.1068] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
BACKGROUND Obstructive sleep apnea (OSA) is associated with obesity, inflammation, and insulin resistance. The role of fat distribution in OSA pathogenesis has not been established in children. The objective of the study is to examine the relationship between fat distribution, OSA, and insulin resistance in an unselected population of obese children. METHODS All obese (BMI > 95th percentile) children (ages 5-18 y) seen at a pediatric obesity clinic were invited to participate. Subjects underwent polysomnography, and were tested for dyslipidemia, inflammation, and insulin resistance measured by the homeostasis model assessment (HOMA). In a subset of subjects, magnetic resonance (MRI) imaging was used to determine the abdominal visceral and subcutaneous adipose tissue areas and magnetic resonance spectroscopy (MRS) spectroscopy was used to intramyocellular lipids in leg muscles. MEASUREMENTS AND MAIN RESULTS 31 obese subjects enrolled and completed polysomnography and serum testing, and 19 subjects underwent MRI/MRS. The mean age was 12.6 ± 3.0 y and the mean body mass index (BMI) was 39.5 ± 11.2 kg/m(2). Forty-eight percent had OSA (mean apnea hypopnea index [AHI] 6.26 ± 6.77 events/h) Subjects with OSA had significantly increased BMI, log HOMA, triglycerides, and leptin compared to those without OSA. In regression analysis, only BMI z-score was associated with log HOMA. In the subset of patients with imaging data, visceral fat area was strongly predictive of AHI (p = 0.003, r(2) = 0.556). BMI z-score, gender, and age were not predictive. CONCLUSIONS Visceral fat distribution is independently predictive of OSA severity in obese children.
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Affiliation(s)
- Craig A Canapari
- Division of Pediatric Pulmonology, Department of Pediatrics, Massachusetts General Hospital, Boston, MA, USA.
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Bredella MA, Torriani M, Ghomi RH, Thomas BJ, Brick DJ, Gerweck AV, Harrington LM, Miller KK. Adiponectin is inversely associated with intramyocellular and intrahepatic lipids in obese premenopausal women. Obesity (Silver Spring) 2011; 19:911-6. [PMID: 21151017 PMCID: PMC3607306 DOI: 10.1038/oby.2010.296] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [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: 01/10/2023]
Abstract
Adiponectin, an adipokine secreted by adipocytes, exerts beneficial effects on glucose and lipid metabolism and has been found to improve insulin resistance by decreasing triglyceride content in muscle and liver in obese mice. Adiponectin is found in several isoforms and the high-molecular weight (HMW) form has been linked most strongly to the insulin-sensitizing effects. Fat content in skeletal muscle (intramyocellular lipids, IMCL) and liver (intrahepatic lipids, IHL) can be quantified noninvasively using proton magnetic resonance spectroscopy ((1)H-MRS). The purpose of our study was to assess the relationship between HMW adiponectin and measures of glucose homeostasis, IMCL and IHL, and to determine predictors of adiponectin levels. We studied 66 premenopausal women (mean BMI 31.0 ± 6.6 kg/m(2)) who underwent (1)H-MRS of calf muscles and liver for IMCL and IHL, computed tomography (CT) of the abdomen for abdominal fat depots, dual-energy X-ray absorptiometry (DXA) for fat and lean mass assessments, HMW and total adiponectin, fasting lipid profile and an oral glucose tolerance test (homeostasis model assessment of insulin resistance (HOMA(IR)), glucose and insulin area under the curve). There were strong inverse associations between HMW adiponectin and measures of insulin resistance, IMCL and IHL, independent of visceral adipose tissue (VAT) and total body fat. IHL was the strongest predictor of adiponectin and adiponectin was a predictor of HOMA(IR). Our study showed that in premenopausal obese women HMW adiponectin is inversely associated with IMCL and IHL content. This suggests that adiponectin exerts positive effects on insulin sensitivity in obesity by decreasing intracellular triglyceride content in skeletal muscle and liver; it is also possible that our results reflect effects of insulin on adiponectin.
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Affiliation(s)
- Miriam A Bredella
- Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts, USA.
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Affiliation(s)
- B J Thomas
- Allen and Hanburys Ltd., Bethnal Green, E.2
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17
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Bredella MA, Torriani M, Ghomi RH, Thomas BJ, Brick DJ, Gerweck AV, Harrington LM, Breggia A, Rosen CJ, Miller KK. Determinants of bone mineral density in obese premenopausal women. Bone 2011; 48:748-54. [PMID: 21195217 PMCID: PMC3073669 DOI: 10.1016/j.bone.2010.12.011] [Citation(s) in RCA: 129] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2010] [Revised: 12/07/2010] [Accepted: 12/13/2010] [Indexed: 01/21/2023]
Abstract
Despite being a risk factor for cardiovascular disease and diabetes mellitus, obesity has been thought to protect against osteoporosis. However, recent studies have demonstrated a differential impact of specific fat compartments on bone mineral density (BMD) with visceral adipose tissue (VAT) having potential detrimental effects on BMD. Visceral obesity is also associated with dysregulation of the GH/IGF-1 axis, an important regulator of bone homeostasis. The purpose of our study was to evaluate the differential effects of abdominal fat depots and muscle, vitamin D, and hormonal determinants, including insulin-like growth factor-1 (IGF-1), testosterone, and estradiol, on trabecular BMD of the lumbar spine. We studied 68 healthy obese premenopausal women (mean BMI, 36.7±4.2 kg/m(2)). Quantitative computed tomography (QCT) was used to assess body composition and lumbar trabecular BMD. There was an inverse association between BMD and VAT, independent of age and BMI (p=0.003). IGF-1 correlated positively with BMD and negatively with VAT and, in stepwise multivariate regression modeling, was the strongest predictor of BMD and procollagen type 1 amino-terminal propeptide (P1NP). Thigh muscle cross sectional area (CSA) and thigh muscle density were also associated with BMD (p<0.05), but 25-hydroxyvitamin D [25(OH)D], testosterone, free testosterone, and estradiol levels were not. 25(OH)D was associated inversely with BMI, total, and subcutaneous abdominal adipose tissue (p<0.05). These findings support the hypothesis that VAT exerts detrimental effects, whereas muscle mass exerts positive effects on BMD in premenopausal obese women. Moreover, our findings suggest that IGF-1 may be a mediator of the deleterious effects of VAT on bone health through effects on bone formation.
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Affiliation(s)
- Miriam A Bredella
- Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Yawkey 6E, 55 Fruit Street, Boston, MA 02114, USA.
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Bredella MA, Torriani M, Ghomi RH, Thomas BJ, Brick DJ, Gerweck AV, Rosen CJ, Klibanski A, Miller KK. Vertebral bone marrow fat is positively associated with visceral fat and inversely associated with IGF-1 in obese women. Obesity (Silver Spring) 2011; 19:49-53. [PMID: 20467419 PMCID: PMC3593350 DOI: 10.1038/oby.2010.106] [Citation(s) in RCA: 236] [Impact Index Per Article: 18.2] [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: 12/27/2022]
Abstract
Recent studies have demonstrated an important physiologic link between bone and fat. Bone and fat cells arise from the same mesenchymal precursor cell within bone marrow, capable of differentiation into adipocytes or osteoblasts. Increased BMI appears to protect against osteoporosis. However, recent studies have suggested detrimental effects of visceral fat on bone health. Increased visceral fat may also be associated with decreased growth hormone (GH) and insulin-like growth factor 1 (IGF-1) levels which are important for maintenance of bone homeostasis. The purpose of our study was to assess the relationship between vertebral bone marrow fat and trabecular bone mineral density (BMD), abdominal fat depots, GH and IGF-1 in premenopausal women with obesity. We studied 47 premenopausal women of various BMI (range: 18-41 kg/m², mean 30 ± 7 kg/m²) who underwent vertebral bone marrow fat measurement with proton magnetic resonance spectroscopy (1H-MRS), body composition, and trabecular BMD measurement with computed tomography (CT), and GH and IGF-1 levels. Women with high visceral fat had higher bone marrow fat than women with low visceral fat. There was a positive correlation between bone marrow fat and visceral fat, independent of BMD. There was an inverse association between vertebral bone marrow fat and trabecular BMD. Vertebral bone marrow fat was also inversely associated with IGF-1, independent of visceral fat. Our study showed that vertebral bone marrow fat is positively associated with visceral fat and inversely associated with IGF-1 and BMD. This suggests that the detrimental effect of visceral fat on bone health may be mediated in part by IGF-1 as an important regulator of the fat and bone lineage.
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Affiliation(s)
- Miriam A Bredella
- Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts, USA.
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Bredella MA, Ghomi RH, Thomas BJ, Miller KK, Torriani M. Comparison of 3.0 T proton magnetic resonance spectroscopy short and long echo-time measures of intramyocellular lipids in obese and normal-weight women. J Magn Reson Imaging 2010; 32:388-93. [PMID: 20677267 DOI: 10.1002/jmri.22226] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
PURPOSE To compare correlations of intramyocellular lipids (IMCL) measured by short and long echo-time proton magnetic resonance spectroscopy (1H-MRS) with indices of body composition and insulin resistance in obese and normal-weight women. MATERIALS AND METHODS We quantified IMCL of tibialis anterior (TA) and soleus (SOL) muscles in 52 premenopausal women (37 obese and 15 normal weight) using single-voxel 1H-MRS PRESS at 3.0 T with short (30 msec) and long (144 msec) echo times. Statistical analyses were performed to determine correlations of IMCL with body composition as determined by computed tomography (CT) and insulin resistance indices and to compare correlation coefficients from short and long echo-time data. Signal-to-noise ratio (SNR), linewidth, and coefficients of variation (CV) of short and long echo-time spectra were calculated. RESULTS Short and long echo-time IMCL from TA and SOL significantly correlated with body mass index (BMI) and abdominal fat depots (r = 0.32 to 0.70, P = <0.05), liver density (r = -0.39 to -0.50, P < 0.05), and glucose area under the curve as a measure of insulin resistance (r = 0.47 to 0.49, P < 0.05). There was no significant difference between correlation coefficients of short and long echo-time spectra (P > 0.5). Short echo-time IMCL in both muscles showed significantly higher SNR (P < 0.0001) and lower CVs when compared to long echo-time acquisitions. Linewidth measures were not significantly different between groups. CONCLUSION IMCL quantification using short and long echo-time 1H-MRS at 3.0 T is useful to detect differences in muscle lipid content in obese and normal-weight subjects. In addition, IMCL correlates with body composition and markers of insulin resistance in this population with no significant difference in correlations between short and long echo-times. Short echo-time IMCL quantification of TA and SOL muscles at 3.0 T was superior to long echo-time due to better SNR and better reproducibility.
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Affiliation(s)
- Miriam A Bredella
- Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts 02114, USA.
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Bredella MA, Ghomi RH, Thomas BJ, Torriani M, Brick DJ, Gerweck AV, Misra M, Klibanski A, Miller KK. Comparison of DXA and CT in the assessment of body composition in premenopausal women with obesity and anorexia nervosa. Obesity (Silver Spring) 2010; 18:2227-33. [PMID: 20111013 PMCID: PMC3607308 DOI: 10.1038/oby.2010.5] [Citation(s) in RCA: 132] [Impact Index Per Article: 9.4] [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: 11/08/2022]
Abstract
Accurate methods for assessing body composition in subjects with obesity and anorexia nervosa (AN) are important for determination of metabolic and cardiovascular risk factors and to monitor therapeutic interventions. The purpose of our study was to assess the accuracy of dual-energy X-ray absorptiometry (DXA) for measuring abdominal and thigh fat, and thigh muscle mass in premenopausal women with obesity, AN, and normal weight compared to computed tomography (CT). In addition, we wanted to assess the impact of hydration on DXA-derived measures of body composition by using bioelectrical impedance analysis (BIA). We studied a total of 91 premenopausal women (34 obese, 39 with AN, and 18 lean controls). Our results demonstrate strong correlations between DXA- and CT-derived body composition measurements in AN, obese, and lean controls (r = 0.77-0.95, P < 0.0001). After controlling for total body water (TBW), the correlation coefficients were comparable. DXA trunk fat correlated with CT visceral fat (r = 0.51-0.70, P < 0.0001). DXA underestimated trunk and thigh fat and overestimated thigh muscle mass and this error increased with increasing weight. Our study showed that DXA is a useful method for assessing body composition in premenopausal women within the phenotypic spectrum ranging from obesity to AN. However, it is important to recognize that DXA may not accurately assess body composition in markedly obese women. The level of hydration does not significantly affect most DXA body composition measurements, with the exceptions of thigh fat.
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Affiliation(s)
- Miriam A Bredella
- Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts, USA.
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Bredella MA, Torriani M, Thomas BJ, Ghomi RH, Brick DJ, Gerweck AV, Miller KK. Peak growth hormone-releasing hormone-arginine-stimulated growth hormone is inversely associated with intramyocellular and intrahepatic lipid content in premenopausal women with obesity. J Clin Endocrinol Metab 2009; 94:3995-4002. [PMID: 19602559 PMCID: PMC2758723 DOI: 10.1210/jc.2009-0438] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [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: 11/19/2022]
Abstract
CONTEXT Visceral adiposity is a strong determinant of GH secretion, and low endogenous GH secretion is associated with increased insulin resistance, a key component of the metabolic syndrome. Increased fat accumulation in skeletal muscle and liver may play an etiological role in the development of insulin resistance and other complications of the metabolic syndrome. Little is known about the role of decreased endogenous GH secretion in the pathogenesis of insulin resistance in obesity. OBJECTIVE To investigate the relationship between intramyocellular lipids (IMCL), intrahepatic lipids, and peak-stimulated GH in premenopausal women with obesity. DESIGN AND SETTING We conducted a cross-sectional study at a clinical translational research center. PATIENTS Patients included 21 premenopausal women with obesity (mean body mass index, 34.0 +/- 4.5 kg/m(2)) and 17 normal-weight controls (mean body mass index, 21.9 +/- 2.0 kg/m(2)) of comparable mean age. MAIN OUTCOMES MEASURES IMCL and intrahepatic lipids were measured with proton magnetic resonance spectroscopy ((1)H-MRS). Body composition was measured with magnetic resonance imaging. Peak GH was measured after stimulation with GHRH-arginine. RESULTS Obese subjects had higher IMCL, intrahepatic lipids, abdominal and thigh fat, and thigh muscle mass compared with normal-weight controls. There were strong inverse associations between peak GH and both IMCL and intrahepatic lipids independent of age and visceral adiposity. There were positive associations between IMCL and intrahepatic lipids with measures of insulin resistance and serum triglycerides. CONCLUSION In premenopausal women with obesity, peak GH is inversely associated with IMCL and intrahepatic lipids independent of age and visceral adiposity. This suggests that low GH may contribute to insulin resistance in obesity through effects on muscle and intrahepatic lipids.
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Affiliation(s)
- Miriam A Bredella
- Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114, USA.
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Taylor-Robinson D, Stacey CM, Jensen JS, Thomas BJ, Munday PE. Further observations, mainly serological, on a cohort of women with or without pelvic inflammatory disease. Int J STD AIDS 2009; 20:712-8. [PMID: 19759049 DOI: 10.1258/ijsa.2008.008489] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
An analysis was undertaken of data pertaining to over 100 women with lower abdominal pain who were laparoscoped. Prior to laparoscopy, 11 of the women were considered to almost certainly have salpingitis, of whom six (55%) had salpingitis at laparoscopy; 17 to probably have salpingitis, of whom six (35%) did; 28 to possibly have salpingitis, of whom five (18%) did; and 56 to be very unlikely to have salpingitis, of whom five (9%) did. Of the 22 women who had salpingitis at laparoscopy, 14 (64%) had a Chlamydia trachomatis IgG antibody titre of >or=1:128 and might reasonably be regarded as having chlamydial disease on this basis; six without such a titre probably did not have chlamydial disease as C. trachomatis could not be detected at any genital site. At laparoscopy, 18 women had adhesions without obvious tubal inflammation; clinically, 15 of them had been regarded as possibly having salpingitis or unlikely to have it, with 12 having chronic pelvic pain. Twelve (67%) of the 18 women had a chlamydial IgG antibody titre of >or=1:128. IgM antibody was also detected most often in the 'salpingitis' group. Of 49 women without any abnormality detected at laparoscopy, nine (18%) had a high chlamydial IgG antibody titre. Overall, a woman who had a high titre of chlamydial IgG antibody and acute pelvic pain, together with a clinical picture of pelvic inflammation, was more likely to have salpingitis than adhesions alone. Likewise, a woman who had a high titre of chlamydial IgG antibody and chronic pelvic pain, together with a clinical picture suggesting that salpingitis was unlikely, was more likely to have adhesions alone than acute chlamydial salpingitis. However, while antibody measurement and seeking cervical C. trachomatis may help in formulating a diagnosis, there seems no simple way of detecting the small proportion of women who are infected by C. trachomatis in the upper genital tract but whose laparoscopic findings indicate normality. So far as patient care is concerned, the only way of preventing damage to the upper genital tract is to treat early on the basis of suspicion.
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Affiliation(s)
- D Taylor-Robinson
- Division of Medicine, Imperial College London, St Mary's Campus, London, UK.
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Abstract
CONTEXT Although women with anorexia nervosa (AN) have severe depletion of body fat, a paradoxical increase in bone marrow fat has been described. Recent data suggest that marrow fat measured by 1H-magnetic resonance spectroscopy (MRS) in combination with bone mineral density (BMD) may be more valuable than either parameter alone in detecting bone weakness. OBJECTIVE The objective of the study was to investigate the effect of AN on accumulation of marrow fat in spine and femur using 1H-MRS and the relationship between marrow fat, BMD, and body composition in subjects with AN and normal-weight controls. DESIGN This was a cross-sectional study. SETTING The study was conducted at a referral center. PATIENTS Patients included 10 women with AN (29.8 +/- 7.6 yr) and 10 normal-weight age-matched women (29.2 +/- 5.2 yr). INTERVENTIONS There were no interventions. MAIN OUTCOMES MEASURE Marrow fat content of the fourth lumbar vertebra and femur measured by 1H-MRS. BMD of spine and hip measured by dual-energy x-ray absorptiometry. RESULTS Subjects with AN had higher marrow fat at the fourth lumbar vertebra and femur compared with controls (P = 0.004-0.01). There was an inverse correlation between marrow fat of L4 and femur and BMD of the spine and hip (r = -0.56 to -0.71, P = 0.01-0.0002) and body mass index and sc adipose tissue of the thigh (r = -0.49 to -0.71, P = 0.03-0.0007). There was an inverse correlation between femur marrow fat and sc and total abdominal adipose tissue (r = -0.53 to -0.67, P = 0.003-0.03). CONCLUSION Women with AN have greater lumbar and femoral marrow fat than controls, and marrow fat correlates inversely with BMD. This paradoxical increase in marrow fat at a time when sc and visceral fat are markedly reduced raises important questions about functional consequences of this process.
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Affiliation(s)
- Miriam A Bredella
- Department of Radiology, Massachusetts General Hospital, Yawkey 6E, 55 Fruit Street, Boston, Massachusetts 02114, USA.
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Ouellette H, Thomas BJ, Kassarjian A, Fritz B, Tétreault P, Palmer WE, Torriani M. Re-examining the association of os acromiale with supraspinatus and infraspinatus tears. Skeletal Radiol 2007; 36:835-9. [PMID: 17415560 DOI: 10.1007/s00256-007-0305-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [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: 10/31/2006] [Revised: 01/02/2007] [Accepted: 02/05/2007] [Indexed: 02/02/2023]
Abstract
PURPOSE To re-evaluate the relationship between os acromiale and rotator cuff tears. METHODS We retrospectively analyzed 84 magnetic resonance imaging studies of the shoulder. Forty-two subjects with os acromiale (n = 42; 32 men and ten women, age 25-81 years, mean 47.6 years) were compared with age- and gender-matched subjects with no evidence of os acromiale (controls). Arthroscopy data were available in 19 os acromiale and 12 control subjects. Statistical analyses were performed to determine differences between groups regarding rotator cuff tears affecting the supraspinatus and infraspinatus tendons detected by magnetic resonance imaging and arthroscopy. Analysis of os acromiale type, ossicle synchondrosis edema, acromioclavicular joint degenerative changes and step-off deformity at the synchondrosis were tabulated. RESULTS No statistically significant difference between the os acromiale and control groups was noted, either on magnetic resonance imaging or arthroscopy, with regard to tears of the supraspinatus (P = 1.000 and 0.981, respectively) and infraspinatus (P = 1.000 and 0.667, respectively) tendons. There was a statistically significant increased number of supraspinatus (P = 0.007) and infraspinatus (P = 0.03) tears in a comparison of subjects with os acromiale and step-off deformity (10/42) vs os acromiale without step-off deformity (32/42). CONCLUSION The presence of os acromiale may not significantly predispose to supraspinatus and infraspinatus tendon tears. However, subjects with step-off deformity of an os acromiale are at greater risk of rotator cuff tears than are similar subjects without such deformity.
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Affiliation(s)
- H Ouellette
- Musculoskeletal Radiology, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 55 Fruit Street, YAW-6046, Boston, MA 02114, USA.
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Fleischman A, Johnsen S, Systrom DM, Hrovat M, Farrar CT, Frontera W, Fitch K, Thomas BJ, Torriani M, Côté HCF, Grinspoon SK. Effects of a nucleoside reverse transcriptase inhibitor, stavudine, on glucose disposal and mitochondrial function in muscle of healthy adults. Am J Physiol Endocrinol Metab 2007; 292:E1666-73. [PMID: 17284576 PMCID: PMC3206591 DOI: 10.1152/ajpendo.00550.2006] [Citation(s) in RCA: 129] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Mitochondrial dysfunction may contribute to the development of insulin resistance and type 2 diabetes. Nucleoside reverse transcriptase inhibitors (NRTIs), specifically stavudine, are known to alter mitochondrial function in human immunodeficiency virus (HIV)-infected individuals, but the effects of stavudine on glucose disposal and mitochondrial function in muscle have not been prospectively evaluated. In this study, we investigated short-term stavudine administration among healthy control subjects to determine effects on insulin sensitivity. A secondary aim was to determine the effects of stavudine on mitochondrial DNA (mtDNA) and function. Sixteen participants without personal or family history of diabetes were enrolled. Subjects were randomized to receive stavudine, 30-40 mg, twice a day, or placebo for 1 mo. Insulin sensitivity determined by glucose infusion rate during the hyperinsulinemic euglycemic clamp was significantly reduced after 1-mo exposure in the stavudine-treated subjects compared with placebo (-0.8 +/- 0.5 vs. +0.7 +/- 0.3 mg.kg(-1).min(-1), P = 0.04, stavudine vs. placebo). In addition, muscle biopsy specimens in the stavudine-treated group showed significant reduction in mtDNA/nuclear DNA (-52%, P = 0.005), with no change in placebo-treated subjects (+8%, P = 0.9). (31)P magnetic resonance spectroscopy (MRS) studies of mitochondrial function correlated with insulin sensitivity measures (r2 = 0.5, P = 0.008). These findings demonstrate that stavudine administration has potent effects on insulin sensitivity among healthy subjects. Further studies are necessary to determine whether changes in mtDNA resulting from stavudine contribute to effects on insulin sensitivity.
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Affiliation(s)
- Amy Fleischman
- Program In Nutritional Metabolism, Massachusetts General Hospital, 55 Fruit St., LON 207, Boston, MA 02114, USA
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Torriani M, Thomas BJ, Bredella MA, Ouellette H. Intramyocellular lipid quantification: comparison between 3.0- and 1.5-T (1)H-MRS. Magn Reson Imaging 2007; 25:1105-11. [PMID: 17707173 PMCID: PMC2034287 DOI: 10.1016/j.mri.2006.12.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2006] [Revised: 12/04/2006] [Accepted: 12/05/2006] [Indexed: 01/08/2023]
Abstract
OBJECTIVE This study aimed to prospectively compare measurement precision of calf intramyocellular lipid (IMCL) quantification at 3.0 and 1.5 T using (1)H magnetic resonance spectroscopy ((1)H-MRS). MATERIALS AND METHODS We examined the soleus and tibialis anterior (TA) muscles of 15 male adults [21-48 years of age, body mass index (BMI)=21.9-38.0 kg/m(2)]. Each subject underwent 3.0- and 1.5-T single-voxel, short-echo-time, point-resolved (1)H-MRS both at baseline and at 31-day follow-up. The IMCL methylene peak (1.3 ppm) was scaled to unsuppressed water peak (4.7 ppm) using the LCModel routine. Full width at half maximum (FWHM) and signal-to-noise ratios (SNRs) of unsuppressed water peak were measured using jMRUI software. Measurement precision was tested by comparing interexamination coefficients of variation (CV) between different field strengths using Wilcoxon matched pairs signed rank test in all subjects. Overweight subjects (BMI>25 kg/m(2)) were analyzed separately to examine the benefits of 3.0-T acquisitions in subjects with increased adiposity. RESULTS No significant difference between 3.0 and 1.5 T was noted in CVs for IMCL of soleus (P=.5). CVs of TA were significantly higher at 3.0 T (P=.02). SNR was significantly increased at 3.0 T for soleus (64%, P<.001) and TA (62%, P<.001) but was lower than the expected improvement of 100%. FWHM at 3.0 T was significantly increased for soleus (19%, P<.001) and TA (7%, P<.01). Separate analysis of overweight subjects showed no significant difference between 3.0- and 1.5-T CVs for IMCL of soleus (P=.8) and TA (P=.4). CONCLUSION Using current technology, (1)H-MRS for IMCL at 3.0 T did not improve measurement precision, as compared with 1.5 T.
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Affiliation(s)
- Martin Torriani
- Division of Musculoskeletal Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA.
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Ouellette H, Salamipour H, Thomas BJ, Kassarjian A, Torriani M. Incidence and MR imaging features of fractures of the anterior process of calcaneus in a consecutive patient population with ankle and foot symptoms. Skeletal Radiol 2006; 35:833-7. [PMID: 16724199 DOI: 10.1007/s00256-006-0154-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [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: 03/09/2006] [Revised: 04/18/2006] [Accepted: 04/20/2006] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To determine the incidence, appearances and associated injuries of fractures affecting the anterior process of calcaneus from a general population with foot and ankle symptoms. DESIGN AND PATIENTS A retrospective review of foot and ankle MR imaging procedures was performed for detection of cases with a fracture affecting the anterior process of calcaneus over a four year period. Radiographs, MR imaging studies, radiology reports, medical records, and operative notes were reviewed. Imaging analysis included fracture pattern, displacement, associated fractures, and presence of tendon and ligamentous injuries. RESULTS The incidence of anterior process of calcaneus fracture on MR imaging was 0.5% (14/2577). Fractures were more common in female subjects (71%, 10/14). Fracture orientation was predominantly vertical (93%, 13/14). No comminuted fractures were seen and only three fractures were displaced. Three of the eight MR imaging evident fractures of anterior process of calcaneus were seen on radiographs. Associated fractures of the talus (n=5), navicular bone (n=3), cuboid (n=2), and calcaneal body (n=1) were noted. Associated injuries to the anterior talofibular ligament (n=3) and tears of the peroneus brevis (n=3) and peroneus longus (n=1) tendons were present. All fractures were treated non-operatively. Two patients had subtalar joint steroid injection for symptomatic relief. CONCLUSIONS Fractures of the anterior process of the calcaneus are uncommon in MR examinations of a general population of patients with foot and ankle symptoms. Although anterior process of calcaneus fractures are rare, there was a moderately high incidence of associated bone and soft-tissue injuries.
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Affiliation(s)
- Hugue Ouellette
- Division of Musculoskeletal Radiology, Massachusetts General Hospital, 55 Fruit Street, Yawkey 6046, Boston, MA 02114, USA.
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Abstract
OBJECTIVE To describe the MR imaging findings of acute and chronic rectus femoris origin (RFO) injuries. MATERIALS AND METHODS A retrospective review of pelvic and hip MR imaging procedures was performed over a 4-year period for detection of cases with injuries to the RFO. Subjects were classified as having either acute or chronic symptoms. MR imaging studies, radiographs, CT scans, radiology reports, medical records, and operative notes were reviewed. Imaging analysis was directed to assess injuries affecting the direct and indirect heads of the RFO. Concurrent osseous, cartilaginous and musculotendinous injuries were tabulated. RESULTS The incidence of RFO injuries on MR imaging was 0.5% (17/3160). With the exception of one case of anterior inferior iliac spine apophysis avulsion and partial tear of the direct head of RFO, all subjects had indirect head of RFO injuries (acute injury 8/9, chronic injury 8/8). Partial tear of the direct head of RFO was less frequently seen (acute injury 3/9, chronic injury 2/8). Partial tears of the conjoint tendon were least frequent (acute 1/9, chronic 2/8). No full-thickness tears of the RFO were noted. Associated labral tears were seen in only one case, with no other concomitant abnormality of the articular cartilage or surrounding soft tissues. All RFO injuries were treated non-operatively. CONCLUSION Injuries of the RFO are uncommon on MR examinations of pelvis/hips and may occur in a sequence progressing from indirect head injury to involvement of direct head and conjoint tendon in more severe cases.
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Affiliation(s)
- Hugue Ouellette
- Musculoskeletal Radiology, Massachusetts General Hospital, Harvard Medical School, 55 Fruit Street, Yaw-6046, Boston, MA 02138, USA.
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Thomas BJ, Byers S, Johnstone EW, Foster BK. The effect of recombinant human osteogenic protein-1 on growth plate repair in a sheep model. J Orthop Res 2005; 23:1336-44. [PMID: 15946820 DOI: 10.1016/j.orthres.2005.03.020.1100230615] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [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: 11/08/2004] [Revised: 03/16/2005] [Accepted: 03/29/2005] [Indexed: 02/04/2023]
Abstract
Injuries to the growth plate in children can result in bone bridge formation, which ultimately lead to limb length and angular deformities. The histological and molecular changes associated with growth plate repair following the Langenskiöld procedure, a surgical technique used to remove impeding bone bridges, in conjunction with administration of recombinant human osteogenic protein-1 (rhOP-1) were examined using a sheep model. Following treatment with rhOP-1 there was an increase in the height of the growth plate immediately adjacent to the defect compared to untreated animals. The expression of type I collagen, osteopontin and decorin were observed in the growth plate adjacent to the defect in the untreated animals at day 56, but this response was accelerated in the rhOP-1 treated animals, with these molecules seen as early as day 7. Therefore, treatment with rhOP-1 initiated a complex response that was both chondrogenic and osteogenic in nature.
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Affiliation(s)
- B J Thomas
- Department of Paediatrics, University of Adelaide, SA, Australia
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Torriani M, Thomas BJ, Barlow RB, Librizzi J, Dolan S, Grinspoon S. Increased intramyocellular lipid accumulation in HIV-infected women with fat redistribution. J Appl Physiol (1985) 2005; 100:609-14. [PMID: 16223978 PMCID: PMC3205444 DOI: 10.1152/japplphysiol.00797.2005] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The human immunodeficiency virus (HIV)-lipodystrophy syndrome is associated with fat redistribution and metabolic abnormalities, including insulin resistance. Increased intramyocellular lipid (IMCL) concentrations are thought to contribute to insulin resistance, being linked to metabolic and body composition variables. We examined 46 women: HIV infected with fat redistribution (n = 25), and age- and body mass index-matched HIV-negative controls (n = 21). IMCL was measured by 1H-magnetic resonance spectroscopy, and body composition was assessed with computed tomography, dual-energy X-ray absorptiometry (DEXA), and magnetic resonance imaging. Plasma lipid profile and markers of glucose homeostasis were obtained. IMCL was significantly increased in tibialis anterior [135.0 +/- 11.5 vs. 85.1 +/- 13.2 institutional units (IU); P = 0.007] and soleus [643.7 +/- 61.0 vs. 443.6 +/- 47.2 IU, P = 0.017] of HIV-infected subjects compared with controls. Among HIV-infected subjects, calf subcutaneous fat area (17.8 +/- 2.3 vs. 35.0 +/- 2.5 cm2, P < 0.0001) and extremity fat by DEXA (11.8 +/- 1.1 vs. 15.6 +/- 1.2 kg, P = 0.024) were reduced, whereas visceral abdominal fat (125.2 +/- 11.3 vs. 74.4 +/- 12.3 cm2, P = 0.004), triglycerides (131.1 +/- 11.0 vs. 66.3 +/- 12.3 mg/dl, P = 0.0003), and fasting insulin (10.8 +/- 0.9 vs. 7.0 +/- 0.9 microIU/ml, P = 0.004) were increased compared with control subjects. Triglycerides (r = 0.39, P = 0.05) and extremity fat as percentage of whole body fat by DEXA (r = -0.51, P = 0.01) correlated significantly with IMCL in the HIV but not the control group. Extremity fat (beta = -633.53, P = 0.03) remained significantly associated with IMCL among HIV-infected patients, controlling for visceral abdominal fat, abdominal subcutaneous fat, and antiretroviral medications in a regression model. These data demonstrate increased IMCL in HIV-infected women with a mixed lipodystrophy pattern, being most significantly associated with reduced extremity fat. Further studies are necessary to determine the relationship between extremity fat loss and increased IMCL in HIV-infected women.
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Affiliation(s)
- Martin Torriani
- Division of Musculoskeletal Radiology, Dept. of Radiology, Massachusetts General Hospital, 55 Fruit St., YAW 6048, Boston, MA 02114, USA.
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Abstract
PURPOSE To prospectively determine the repeatability and variability of tibialis anterior intramyocellular lipid (IMCL) quantifications performed by using 1.5-T hydrogen 1 (1H) magnetic resonance (MR) spectroscopy in healthy subjects. MATERIALS AND METHODS Institutional review board approval and written informed consent were obtained for this Health Insurance Portability and Accountability Act-compliant study. The authors examined the anterior tibial muscles of 27 healthy subjects aged 19-48 years (12 men, 15 women; mean age, 25 years) by using single-voxel short-echo-time point-resolved 1H MR spectroscopy. During a first visit, the subjects underwent 1H MR spectroscopy before and after being repositioned in the magnet bore, with voxels carefully placed on the basis of osseous landmarks. Measurements were repeated after a mean interval of 12 days. All spectra were fitted by using Java-based MR user interface (jMRUI) and LCModel software, and lipid peaks were scaled to the unsuppressed water peak (at 4.7 ppm) and the total creatine peak (at approximately 3.0 ppm). A one-way random-effects variance components model was used to determine intraday and intervisit coefficients of variation (CVs). A power analysis was performed to determine the detectable percentage change in lipid measurements for two subject sample sizes. RESULTS Measurements of the IMCL methylene protons peak at a resonance of 1.3 ppm scaled to the unsuppressed water peak (IMCL(W)) that were obtained by using jMRUI software yielded the lowest CVs overall (intraday and intervisit CVs, 13.4% and 14.4%, respectively). The random-effects variance components model revealed that nonbiologic factors (equipment and repositioning) accounted for 50% of the total variability in IMCL quantifications. Power analysis for a sample size of 20 subjects revealed that changes in IMCL(W) of greater than 15% could be confidently detected between 1H MR spectroscopic measurements obtained on different days. CONCLUSION 1H MR spectroscopy is feasible for repeatable quantification of IMCL concentrations in longitudinal studies of muscle metabolism.
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Affiliation(s)
- Martin Torriani
- Division of Musculoskeletal Imaging and Institute for Technology Assessment, Massachusetts General Hospital and Harvard Medical School, 15 Parkman St, WACC 515, Boston, MA 02114, USA.
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Zhang Z, Henderson C, Perfect E, Carver TLW, Thomas BJ, Skamnioti P, Gurr SJ. Of genes and genomes, needles and haystacks: Blumeria graminis and functionality. Mol Plant Pathol 2005; 6:561-75. [PMID: 20565680 DOI: 10.1111/j.1364-3703.2005.00303.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
SUMMARY Here, we consider the barley powdery mildew fungus, Blumeria graminis (DC Speer) f.sp. hordei (Marchal), and review recent research which has added to our understanding of the biology and molecular biology which underpins the asexual life cycle of this potentially devastating pathogen. We focus on the early stages of the host-pathogen interaction and report current understanding in the areas of leaf perception, fungal signal transduction and host-imposed oxidative stress management. Through this, it is becoming increasingly clear how closely and subtly both sides of the relationship are regulated. Collectively, however, this review highlights the high degree of complexity in working with an obligate parasite. Our experiences suggest that we would make more efficient progress towards understanding the basis of susceptibility and resistance to this true obligate biotroph if its genome sequence was available.
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Affiliation(s)
- Z Zhang
- Plant Sciences Department, South Parks Road, University of Oxford, Oxford OX1 3RB, UK
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Abstract
OBJECTIVE The objective of our study was to create and validate an automated computerized method for the categorization of narrative text radiograph reports. MATERIALS AND METHODS Using commercially available software with embedded Boolean logic, we created a text search algorithm to categorize reports of radiography examinations into "fracture,"normal," and "neither normal nor fracture." The algorithm was refined and optimized through repeated testing on 512 consecutive ankle radiography reports from a single clinical imaging center. The final algorithm was applied on a different set of 750 consecutive radiography reports of the spine and extremities produced at three different clinical imaging sites and interpreted by 44 different radiologists. Expert reviewers assessed the accuracy of the final classification. The chi-square test or Fisher's exact test was performed to determine the reproducibility of results across different clinical imaging sites. RESULTS The computerized classification was highly accurate for the classification of radiography reports into "normal" (specificity, 91.6%; sensitivity, 91.3%), "neither normal nor fracture"(sensitivity, 87.8%; specificity, 94.9%), and "fracture"(sensitivity, 94.1%; specificity, 98.1%) categories. This performance showed no significant difference across the three sites (p >0.05). CONCLUSION Computerized categorization of narrative-text radiography reports is highly sensitive and specific and can be used to classify reports from different imaging sites generated by different radiologists. This method can be an extremely powerful tool in future cost-effectiveness studies, health care policy studies, operations assessments, and quality control.
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Affiliation(s)
- Bijoy J Thomas
- Division of Musculoskeletal Radiology, Department of Radiology, Massachusetts General Hospital, 32 Fruit St., YAW 6E, Boston, MA 02114, USA
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Moulds JM, Thomas BJ, Doumbo O, Diallo DA, Lyke KE, Plowe CV, Rowe JA, Birmingham DJ. Identification of the Kna/Knb polymorphism and a method for Knops genotyping. Transfusion 2004; 44:164-9. [PMID: 14962306 PMCID: PMC2877259 DOI: 10.1111/j.1537-2995.2004.00615.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND DNA mutations resulting in the McCoy and Swain-Langley polymorphisms have been identified on complement receptor 1 (CR1)-a ligand for rosetting of Plasmodium falciparum-infected RBCs. The molecular identification of the Kna/Knb polymorphism was sought to develop a genotyping method for use in the study of the Knops blood group and malaria. STUDY DESIGN AND METHODS CR1 deletion constructs were used in inhibition studies of anti-Kna. PCR amplification of Exon 29 was followed by DNA sequencing. A PCR-RFLP was developed with NdeI, BsmI, and MfeI for the detection of Kna/Knb, McCa/McCb, and Sl1/Sl2, respectively. Knops phenotypes were determined with standard serologic techniques. RESULTS A total of 310 Malian persons were phenotyped for Kna with 200 (64%) Kn(a+) and 110 (36%) Kn(a-). Many of the Kn(a-) exhibited the Knops-null phenotype, that is, Helgeson. The Kna/b DNA polymorphism was identified as a V1561M mutation with allele frequencies of Kna (V1561) 0.9 and Knb (M1561) 0.1. CONCLUSION The high frequency (18%) of Knb in West African persons suggests that it is not solely a Caucasian trait. Furthermore, because of the high incidence of heterozygosity as well as amorphs, accurate Knops typing of donors of African descent is best accomplished by a combination of molecular and serologic techniques.
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Affiliation(s)
- J M Moulds
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania 19129, USA.
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Affiliation(s)
- Hugue Ouellette
- Division of Musculoskeletal Radiology, Department of Radiology, Massachusetts General Hospital, 15 Parkman St., WACC 515, Boston, MA 02114, USA
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Abstract
Theory supports the use of a segmental methodology (SM) for bioimpedance analysis (BIA) of body water (BW). However, previous studies have generally failed to show a significant improvement when the SM is used in place of a whole-body methodology. A pilot study was conducted to compare the two methodologies in control and overweight subjects. BW of each subject was measured by D(2)O dilution and also estimated from BIA measurements. Bland and Altman analysis was used to compare the two values of BW. The SM resulted in a small but not significantly improved "limits of agreement" of measured and BIA estimated BW (approximately 0.3). This and the results of previous studies suggest that improvements in prediction of BW obtained from application of the SM may be intrinsically small and may not justify the additional effort in application.
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Affiliation(s)
- B J Thomas
- School of Physical and Chemical Sciences, Queensland University of Technology, 2434, Q4001, Brisbane, Australia.
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Dragoo JL, Samimi B, Zhu M, Hame SL, Thomas BJ, Lieberman JR, Hedrick MH, Benhaim P. Tissue-engineered cartilage and bone using stem cells from human infrapatellar fat pads. J Bone Joint Surg Br 2003; 85:740-7. [PMID: 12892203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
Abstract
Multipotential processed lipoaspirate (PLA) cells extracted from five human infrapatellar fat pads and embedded into fibrin glue nodules, were induced into the chondrogenic phenotype using chondrogenic media. The remaining cells were placed in osteogenic media and were transfected with an adenovirus carrying the cDNA for bone morphogenetic protein-2 (BMP-2). We evaluated the tissue-engineered cartilage and bone using in vitro techniques and by placing cells into the hind legs of five severe combined immunodeficient mice. After six weeks, radiological and histological analysis indicated that the PLA cells induced into the chondrogenic phenotype had the histological appearance of hyaline cartilage. Cells transfected with the BMP-2 gene media produced abundant bone, which was beginning to establish a marrow cavity. Tissue-engineered cartilage and bone from infrapatellar fat pads may prove to be useful for the treatment of osteochondral defects.
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Affiliation(s)
- J L Dragoo
- Department of Orthopaedic Surgery, UCLA Medical Centre, Los Angeles, California 90095-6092, USA
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Kingston-Smith AH, Bollard AL, Armstead IP, Thomas BJ, Theodorou MK. Proteolysis and cell death in clover leaves is induced by grazing. Protoplasma 2003; 220:119-129. [PMID: 12664276 DOI: 10.1007/s00709-002-0044-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Programmed plant cell death is a widespread phenomenon resulting in the formation of xylem vessels, dissected leaf forms, and aerenchyma. We demonstrate here that some characteristics of programmed cell death can also be observed during the cellular response to biotic and abiotic stress when plant tissue is ingested by grazing ruminants. Furthermore, the onset and progression of plant cell death processes may influence the proteolytic rate in the rumen. This is important because rapid proteolysis of plant proteins in ruminants is a major cause of the inefficient conversion of plant to animal protein resulting in the release of environmental N pollutants. Although rumen proteolysis is widely believed to be mediated by proteases from rumen microorganisms, proteolysis and cell death occurred concurrently in clover leaves incubated in vitro under rumenlike conditions (maintained anaerobically at 39 degrees C) but in the absence of a rumen microbial population. Under rumenlike conditions, both red and white clover cells showed progressive loss of DNA, but this was only associated with fragmentation in white clover. Cell death was indicated by increased ionic leakage and the appearance of terminal deoxynucleotidyl transferase-mediated dUTP-nick-end-labelled nuclei. Foliar protein decreased to 50% of the initial values after 3 h incubation in white clover and after 4 h in red clover, while no decrease was observed in ambient (25 degrees C, aerobic) incubations. In white clover, decreased foliar protein coincided with an increased number of protease isoforms.
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Affiliation(s)
- A H Kingston-Smith
- Department of Animal Science and Microbiology, Institute of Grassland and Environmental Research, Aberystwyth, Ceredigion, United Kingdom
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Taylor-Robinson D, Aduse-Opoku J, Sayed P, Slaney JM, Thomas BJ, Curtis MA. Oro-dental bacteria in various atherosclerotic arteries. Eur J Clin Microbiol Infect Dis 2002; 21:755-7. [PMID: 12415477 DOI: 10.1007/s10096-002-0810-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [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: 10/27/2022]
Abstract
Chlamydia pneumoniae DNA has been detected in at least 40% of all major arteries affected by atherosclerosis, but several other microorganisms have also been detected. In this study, diseased vessels were evaluated for the presence of the DNA of seven oro-dental bacteria and two nonoral bacteria. A polymerase chain reaction technique was employed using primer pairs based on 16S rRNA genes. Of 32 specimens tested, 10 (31.2%) were DNA positive: seven for Actinobacillus actinomycetemcomitans and three for Prevotella intermedia. The DNA was found in specimens from the aorta and the iliac, internal mammary and coronary arteries. Eleven (35.4%) of 31 specimens had been shown previously to be positive for Chlamydia pneumoniae DNA. A mixture of chlamydiae and oro-dental bacteria was found in three cases. These findings may have implications for antibiotic prophylaxis of coronary heart disease if directed solely at Chlamydia pneumoniae.
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Affiliation(s)
- D Taylor-Robinson
- Imperial College School of Medicine, St. Mary's Campus, Winston Churchill Wing, Paddington, London W2 1NY, United Kingdom,
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Abstract
AIM To determine the prevalence of Chlamydia pneumoniae DNA in infrequently examined blood vessels. METHODS Vessels obtained from 15 men and six women at coronary artery bypass surgery were tested by a nested polymerase chain reaction (PCR) assay for C pneumoniae DNA. RESULTS Chlamydia pneumoniae DNA was detected in four of six atheromatous ascending aorta specimens but in none of eight non-atheromatous aorta specimens, in six of 11 atheromatous internal mammary artery specimens but in none of seven non-atheromatous internal mammary artery specimens, in five of seven long saphenous vein specimens showing evidence of disease but in none of 12 specimens without evidence of disease, and in two of three previously grafted veins. Overall, C pneumoniae occurred significantly more often in diseased than in normal vessels (p = < 0.00001). CONCLUSIONS Chlamydia pneumoniae is often present in diseased areas of arteries, including the internal mammary arteries, and even in diseased areas of veins. It is not present in apparently healthy areas of either type of vessel.
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Affiliation(s)
- D Taylor-Robinson
- Department of Genitourinary Medicine, Imperial College School of Medicine, St Mary's Campus, Paddington, London, UK
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Abstract
The recent sequencing of the complete genome of the fruit fly Drosophila melanogaster has yielded about 30% of the predicted genes with no obvious counterparts in other organisms. These rapidly evolving genes remain largely unexplored. Here, we present evidence for a striking variability in an important Drosophila cell cycle regulator encoded by the gene roughex (rux) in closely related fly species. The unusual level of Rux protein variability indicates that there are very low overall constraints on amino acid substitutions. Despite the lack of sequence similarity, certain common features, including the presence of a C-terminal nuclear localization signal and a functionally important N-terminal RXL cyclin-binding motif, exist between Rux and cyclin-dependent kinase inhibitors of the Cip/Kip family. These results indicate that even some genes involved in key regulatory processes in eukaryotes evolve at extremely high rates.
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Affiliation(s)
- S N Avedisov
- Laboratory of Biochemistry, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA.
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Thomas BJ, Pierpoint T, Taylor-Robinson D, Renton AM. Qualitative and quantitative aspects of the ligase chain reaction assay for Chlamydia trachomatis in genital tract samples and urines. Int J STD AIDS 2001; 12:589-94. [PMID: 11516368 DOI: 10.1258/0956462011923769] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The performance of the ligase chain reaction (LCR) assay for Chlamydia trachomatis was evaluated in a genitourinary medicine (GUM) clinic population. Its sensitivity was 100%, 91% and 95%, respectively, for cervical, vaginal and urine samples from 417 women, when compared with direct fluorescent antibody (DFA) staining of cervical samples, and 100% and 91%, respectively, for urethral and urine samples from 317 men, when compared with DFA staining of urethral smears. An enzyme immunoassay (EIA) was only 65% sensitive for cervical samples. Urethral swabs from a number of treated men remained LCR-positive when antigen was no longer detectable by DFA staining. An association between quantitative data from the LCR assay (i.e. the optical density of samples, measured in relation to internal controls and calibrators) and the antigen load of the samples, measured by DFA staining, indicated a lack of significant inhibition in the LCR assay in this study. This was probably due to freezing of the samples before testing. Diluting 20 LCR-positive urines with a range of antigen loads resulted in loss of positivity in 3, and a reduction in the signal in 13. The implications of the antigen load on the performance of detection assays for chlamydia-positive patients are discussed.
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Affiliation(s)
- B J Thomas
- Department of Genitourinary Medicine, Imperial College School of Medicine, St Mary's Hospital, London W2 1NY, UK
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Ougham HJ, Thomas AM, Thomas BJ, Frick GA, Armstrong GA. Both light-dependent protochlorophyllide oxidoreductase A and protochlorophyllide oxidoreductase B are down-regulated in the slender mutant of barley. J Exp Bot 2001; 52:1447-1454. [PMID: 11457904 DOI: 10.1093/jexbot/52.360.1447] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The gibberellin-insensitive overgrowth mutant of barley, slender, exhibits altered expression of a number of nuclear genes in comparison with the wild type. There is a particularly marked reduction in slender seedlings of transcript encoding protochlorophyllide oxidoreductase (POR), the enzyme which catalyses the penultimate and only light-requiring step in chlorophyll biosynthesis. The expression of the two barley genes encoding light-dependent POR, PORA and PORB was investigated. Expression of both genes was found to be reduced in slender seedlings relative to the wild type, in both etiolated and light-grown leaf tissue; this was most marked in the zone of rapid cell extension. Western blot analysis showed that POR protein was also less abundant in etiolated and in light-grown slender than in the equivalent wild-type leaf tissue, although the effect was less pronounced than at the transcript level. Protochlorophyllide content in etiolated slender seedlings was reduced in comparison with wild-type seedlings, though chlorophyll content in light-grown leaf blades was unaffected. The reduction in POR expression in slender barley may reflect a novel response to the constitutive activation of gibberellin signalling in this mutant. Despite the consequences of the mutation for POR gene expression, slender seedlings develop apparently normal chloroplasts in the light, and etioplasts with well-defined prolamellar bodies when grown in continuous darkness. This suggests that the POR content of wild-type barley seedlings is well in excess of the minimum required for normal plastid development.
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Affiliation(s)
- H J Ougham
- Cell Biology Department, Institute of Grassland and Environmental Research, Plas Gogerddan, Aberystwyth, Ceredigion SY23 3EB, Wales, UK.
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Cornish BH, Chapman M, Hirst C, Mirolo B, Bunce IH, Ward LC, Thomas BJ. Early diagnosis of lymphedema using multiple frequency bioimpedance. Lymphology 2001; 34:2-11. [PMID: 11307661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Multiple frequency bioelectrical impedance analysis (MFBIA) has previously been shown to provide accurate relative measures of lymphedema in the upper limb of patients (1). This paper reports the results of a three year prospective study to evaluate the efficacy of MFBIA to predict the early onset of lymphedema in patients following treatment for breast cancer. Bioelectrical impedance measurements and circumferential measurements of each upper limb were recorded in healthy control subjects (n = 60) to determine the normal range of the ratio (dominant/non-dominant) of extracellular and total limb volumes respectively. Patients undergoing surgery for the treatment of breast cancer were recruited as the study group; MFBIA and circumferential measurements were recorded pre-surgery, one month post-surgery and then at two month intervals for 24 months. One hundred and two patients were recruited into the study. Twenty patients developed lymphedema in the 24 months follow up period of this study. In each of these 20 cases MFBIA predicted the onset of the condition up to 10 months before the condition could be clinically diagnosed. Estimates of the sensitivity and specificity were both approximately 100%. At the time of detection by MFBIA, only one of the patients returned a positive test result from the total limb volumes determined from the circumferential measures. These results confirmed the suitability of the MFBIA technique as a reliable diagnostic procedure for the early detection of lymphedema.
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Affiliation(s)
- B H Cornish
- Centre for Medical & Health Physics, Queensland University of Technology, Australia.
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Abstract
PURPOSE This study was designed to investigate the immediate effect of exercise intensity and duration on body fluid volumes in rats throughout a 3-wk exercise program. METHODS Changes in the extracellular water (ECW) and total body water (TBW) volumes of rats were measured preexercise and postexercise using multiple frequency bioelectrical impedance analysis. Groups of rats were exercised at two intensities (6 m.min(-1) and 12 m.min(-1)) for two exercise times (60 min and 90 min) 5 d.wk(-1) during a 3-wk period. Changes in plasma electrolytes, glucose, and lactate resulting from the exercise were also measured on 3 d of each week. RESULTS Each group of animals showed significant losses in ECW and TBW as a direct result of daily exercise. The magnitude of fluid loss was directly related to the intensity of the exercise, but not to exercise duration; although the magnitude of daily fluid loss at the higher intensity exercise (12 m.min(-1)) decreased as the study progressed, possibly indicating a training effect. CONCLUSION At low-intensity exercise, there is a small but significant loss in both TBW and ECW fluids, and the magnitude of these losses does not change throughout a 3-wk exercise program. At moderate levels of exercise intensity, there is a greater loss of both TBW and ECW fluids. However, the magnitudes of these losses decrease significantly during the 3-wk exercise program, thus demonstrating a training effect.
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Affiliation(s)
- B H Cornish
- Centre for Medical and Health Physics, Queensland University of Technology, Brisbane, Australia.
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Abstract
Differentiation in the developing Drosophila eye requires synchronization of cells in the G(1) phase of the cell cycle. The roughex gene product plays a key role in this synchronization by negatively regulating cyclin A protein levels in G(1). We show here that coexpressed Roughex and cyclin A physically interact in vivo. Roughex is a nuclear protein, while cyclin A was previously shown to be exclusively cytoplasmic during interphase in the embryo. In contrast, we demonstrate that in interphase cells in the eye imaginal disk cyclin A is present in both the nucleus and the cytoplasm. In the presence of ectopic Roughex, cyclin A becomes strictly nuclear and is later degraded. Nuclear targeting of both Roughex and cyclin A under these conditions is dependent on a C-terminal nuclear localization signal in Roughex. Disruption of this signal results in cytoplasmic localization of both Roughex and cyclin A, confirming a physical interaction between these molecules. Cyclin A interacts with both Cdc2 and Cdc2c, the Drosophila Cdk2 homolog, and Roughex inhibits the histone H1 kinase activities of both cyclin A-Cdc2 and cyclin A-Cdc2c complexes in whole-cell extracts. Two-hybrid experiments suggested that the inhibition of kinase activity by Roughex results from competition with the cyclin-dependent kinase subunit for binding to cyclin A. These findings suggest that Roughex can influence the intracellular distribution of cyclin A and define Roughex as a distinct and specialized cell cycle inhibitor for cyclin A-dependent kinase activity.
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Affiliation(s)
- S N Avedisov
- Laboratory of Biochemistry, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-4255, USA
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Nelson M, Lean ME, Connor H, Thomas BJ, Lord K, Hartland B, Waldron S, McGough N, Walker L, Ryan A, Start K. Survey of dietetic provision for patients with diabetes. Diabet Med 2000; 17:565-71. [PMID: 11073177 DOI: 10.1046/j.1464-5491.2000.00337.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [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: 11/20/2022]
Abstract
AIMS To survey dietitians involved in diabetes care regarding the provisions for patients with diabetes. METHODS A national survey of 512 dietitians known to be engaged in provision of diabetes care was conducted in 1997 and 391 (76%) responded. RESULTS Nationally the median provision of dietetic care for diabetes reported was 10.7 h per 100,000 general population per week, but the provision was uneven ranging from 2.0 to 27.6 h per 100,000. Eighty-five per cent of dietitians worked in areas where the provision was less than 22 h per 100,000 general population per week (the current recommended minimum standard). Dietetic provision was greater in secondary care (median 9.1 h per 100,000 general population per week) than in general practice, residential homes and other locations (median 4.4 h per 100,000 general population per week). Provision was greater in those areas in which a designated dietitian had responsibility for co-ordinating the dietetic service for diabetes than in areas where the co-ordinator was not a dietitian or where there was no co-ordinator. Over 90% of dietitians reported following British Diabetic Association (BDA) recommendations regarding advice on carbohydrate, sugar, fat and fibre consumption, but only one-third routinely advised on salt restriction. Of the 17% of dietitians who continue to use carbohydrate exchanges, all combine this method with other approaches. Of the recommendations made by the Clinical Standards Group, only 69% of dietitians reported seeing more than half of newly diagnosed adult patients within four weeks, and less than 50% reported offering half or more of their patients an annual review. Amongst the literature in current use, 98% of dietitians use BDA literature for teaching patients and 90% use BDA publications in their own education. Seventy-six per cent of dietitians believed that there was a role for commercial slimming organizations in weight management of people with diabetes. CONCLUSIONS Given the proven value of dietetic input in diabetes management, there would be advantages to correcting the regional inequalities in dietetic provision for diabetes care in the UK.
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Affiliation(s)
- M Nelson
- Department of Nutrition and Dietetics, King's College London, UK
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Keane FE, Thomas BJ, Gilroy CB, Renton A, Taylor-Robinson D. The association of Chlamydia trachomatis and Mycoplasma genitalium with non-gonococcal urethritis: observations on heterosexual men and their female partners. Int J STD AIDS 2000; 11:435-9. [PMID: 10919484 DOI: 10.1258/0956462001916209] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Our objectives were to study the distribution of Chlamydia trachomatis and Mycoplasma genitalium in men with or without non-gonococcal urethritis (NGU) and their respective female partners. A case-control study was carried out to which men with or without NGU and their female partners were recruited. All study participants were tested for the presence of C. trachomatis and M. genitalium. An analysis firstly of the distribution of each of these microorganisms among men with or without urethritis and their respective female partners was carried out. Furthermore, we examined the association of each of these microorganisms and NGU when the other had been excluded. Chlamydia trachomatis was present in 14 (36%) of 39 men with NGU compared to none of 12 men without NGU (P=0.022). The prevalence rates for female partners of men with NGU were 10 (26%) of 39 compared to none of 12 partners of men without NGU (P=0.092). M. genitalium was detected in 12 (33%) of 36 men with NGU compared to 1 (9%) of men without NGU (not significant; P=0.147). The prevalence rates for female partners of men with NGU were 10 (32%) of 31 women compared to none of 7 partners of men without NGU (not significant; P=0.156). There was a greater concordance than discordance of carriage of each of the 2 microorganisms among the study couples and each tended to be carried independently of the other by men. Analysis of the association between the presence of C. trachomatis in men and NGU was significantly improved by the exclusion of men with M. genitalium (P=0.0058). Likewise, the association between the presence of M. genitalium in men and NGU was significantly improved by the exclusion of couples in whom either the man or woman was C. trachomatis-positive (P=0.049). The independent carriage of C. trachomatis and M. genitalium by men with NGU, coupled with the improved association between each pathogen and NGU by exclusion of the other provides support for the separate role of each in the aetiology of NGU.
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Affiliation(s)
- F E Keane
- Division of Medicine, Imperial College School of Medicine, St Mary's Hospital, London, UK
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Keane FE, Thomas BJ, Gilroy CB, Renton A, Taylor-Robinson D. The association of Mycoplasma hominis, Ureaplasma urealyticum and Mycoplasma genitalium with bacterial vaginosis: observations on heterosexual women and their male partners. Int J STD AIDS 2000; 11:356-60. [PMID: 10872907 DOI: 10.1258/0956462001916056] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The prevalence of 3 mycoplasmas (Mycoplasma hominis, Ureaplasma urealyticum and Mycoplasma genitalium) was determined in a cohort of women with or without bacterial vaginosis (BV) and in their respective male partners. Heterosexual women with or without BV and their male partners were recruited and genital sampling for these microorganisms was performed. Seventeen women with BV and 21 women with normal flora, and their respective male partners, were recruited. M. hominis was present in 9 (53%) of 17 women with BV compared with none of 21 women without BV (P=0.0001). Of the 17 male partners of women with BV, 8 (47%) had M. hominis compared to 5 (24%) of 21 male partners of women without BV (not significant [n/s]). U. urealyticum was detected in 11 (65%) of 17 women with BV in comparison with 10 (48%) of 21 women without BV (n/s). U. urealyticum was present in 4 (24%) of 17 male partners of women with BV compared to 6 (29%) of 21 male partners of women without BV (n/s). M. genitalium was not detected in any of 15 women with BV and in only 2 (12%) of 17 women without BV (n/s). M. genitalium was present in 4 (25%) male partners of 16 women with BV in comparison with 3 (16%) male partners of 19 women without BV (n/s). Thus, M. hominis was the only mycoplasma detected significantly more often in women with, rather than in those without, BV. None of the mycoplasmas was found significantly more often in male partners of women with, rather than those without, BV. Overall, M. genitalium behaved somewhat similar to Chlamydia trachomatis. It was the least commonly occurring mycoplasma, a reflection perhaps of the relatively low incidence of partner change in this study population.
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Affiliation(s)
- F E Keane
- Division of Medicine, Imperial College School of Medicine, St Mary's Hospital, London, UK
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