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1.
Breast Cancer Res Treat ; 174(3): 669-677, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30612274

ABSTRACT

PURPOSE: Linear tumor size (T-size) estimated with conventional histology informs breast cancer management. Previously we demonstrated significant differences in margin and focality estimates using conventional histology versus digital whole-mount serial sections (WMSS). Using WMSS we can measure T-size or volume. Here, we compare WMSS T-size with volume, and with T-size measured conventionally. We also compare the ellipsoid model for calculating tumor volume to direct, WMSS measurement. METHODS: Two pathologists contoured regions of invasive carcinoma and measured T-size from both WMSS and (simulated) conventional sections in 55 consecutive lumpectomy specimens. Volume was measured directly from the contours. Measurements were compared using the paired t-test or Spearman's rank-order correlation. A five-point 'border index' was devised and assigned to each case to parametrize tumor shape considering 'compactness' or cellularity. Tumor volumes calculated assuming ellipsoid geometry were compared with direct, WMSS measurements. RESULTS: WMSS reported significantly larger T-size than conventional histology in the majority of cases [61.8%, 34/55; means = (2.34 cm; 1.99 cm), p < 0.001], with a 16.4% (9/55) rate of 'upstaging'. The majority of discordances were due to undersampling. T-size and volume were strongly correlated (r = 0.838, p < 0.001). Significantly lower volume was obtained with WMSS versus ellipsoid modeling [means = (1.18 cm3; 1.45 cm3), p < 0.001]. CONCLUSIONS: Significantly larger T-size is measured with WMSS than conventionally, due primarily to undersampling in the latter. Volume and linear size are highly correlated. Diffuse tumors interspersed with normal or non-invasive elements may be sampled less extensively than more localized masses. The ellipsoid model overestimates tumor volume.


Subject(s)
Breast Neoplasms/surgery , Histological Techniques/methods , Imaging, Three-Dimensional/methods , Neoplasm Invasiveness/pathology , Breast Neoplasms/diagnostic imaging , Breast Neoplasms/pathology , Female , Humans , Margins of Excision , Mastectomy, Segmental , Neoplasm Invasiveness/diagnostic imaging , Specimen Handling , Tumor Burden
3.
Mucosal Immunol ; 12(2): 580, 2019 03.
Article in English | MEDLINE | ID: mdl-30514887

ABSTRACT

The original version of this Article omitted the author Margarita Parada-kusz from the Center for Computational and Integrative Biology, Massachusetts General Hospital, Boston, MA, USA.

4.
Clin Exp Immunol ; 194(1): 103-117, 2018 10.
Article in English | MEDLINE | ID: mdl-30260475

ABSTRACT

Polymorphonuclear (PMN) leucocytes participate in acute inflammatory pathologies such as acute respiratory distress syndrome (ARDS) following traumatic injury and shock, which also activates the coagulation system systemically. Trauma can prime the PMN nicotinamide adenine dinucleotide phosphate (NADPH) oxidase complex for an enhanced respiratory burst, but the relative role of various priming agents in this process remains incompletely understood. We therefore set out to identify mediators of PMN priming during coagulation and trauma-shock and determine whether PMN reactive oxygen species (ROS) generated in this manner could influence organ injury and coagulation. Initial experiments demonstrated that PMN are primed for predominantly extracellular ROS production by products of coagulation, which was abrogated by CD88/C5a receptor(C5aR) inhibition. The importance of this was highlighted further by demonstrating that known PMN priming agents result in fractionally different amounts of extracellular versus intracellular ROS release depending on the agent used. Plasma from trauma patients in haemodynamic shock (n = 10) also primed PMN for extracellular ROS in a C5a-dependent manner, which correlated with both complement alternative pathway activation and thrombin generation. Furthermore, PMN primed by preincubation with products of blood coagulation directly caused loss of endothelial barrier function in vitro that was abrogated by C5aR blockade or NADPH oxidase inhibition. Finally, we show in a murine model of trauma-shock that p47phox knock-out (KO) mice with PMN incapable of generating ROS were protected from inflammatory end-organ injury and activated protein C-mediated coagulopathy. In summary, we demonstrate that trauma-shock and coagulation primes PMN for predominantly extracellular ROS production in a C5a-dependent manner that contributes to endothelial barrier loss and organ injury, and potentially enhances traumatic coagulopathy.


Subject(s)
Blood Coagulation/physiology , Neutrophils/immunology , Reactive Oxygen Species/metabolism , Receptor, Anaphylatoxin C5a/antagonists & inhibitors , Shock/pathology , Wounds and Injuries/pathology , Adult , Aged , Animals , Female , Humans , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Middle Aged , NADPH Oxidases/antagonists & inhibitors , NADPH Oxidases/genetics , NADPH Oxidases/metabolism , Neutrophil Activation/immunology , Respiratory Burst , Respiratory Distress Syndrome/immunology , Respiratory Distress Syndrome/pathology , Shock/immunology , Thrombin/biosynthesis , Wounds and Injuries/immunology
5.
Breast Cancer Res Treat ; 170(1): 169-177, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29520532

ABSTRACT

PURPOSE: We have limited capability to predict survival among patients treated for metastatic HER2-positive breast cancer. Further research is warranted to identify significant prognostic and predictive factors. METHODS: We identified all HER2-positive metastatic breast cancer patients receiving trastuzumab at the Sunnybrook Odette Cancer Centre (SOCC) from 1999 to 2013 through the Cancer Care Ontario (CCO) Registry (n = 256) and selected patients with available pathology reports (n = 154). A retrospective review was completed documenting clinical, pathologic, and laboratory characteristics at the time of first trastuzumab therapy and survival outcomes. Cox proportional hazards regression models were used to identify prognostic factors for overall survival (OS) (primary endpoint) and failure-free survival (FFS), adjusted for the known prognostic factors of the presence of CNS metastases and the presence of ≥ 2 distant metastatic sites. RESULTS: A multivariable model identified older age [hazard ratio (HR) 1.18/decade, 95% confidence interval (CI) 1.02-1.37)], increased platelet-to-lymphocyte ratio (PLR) (HR 1.75/log-unit, 95% CI 1.25-2.46), increased serum alkaline phosphatase (ALP) (HR 1.87/log-unit, 95% CI 1.41-2.49), and ER positivity (HR 0.63, 95% CI 0.42-0.96) as significant prognostic factors for OS after adjusting for the presence of CNS metastasis (HR 3.19, 95% CI 1.59-6.38) and the presence of ≥ 2 distant metastatic sites (HR 2.10, 95% CI 1.19-3.70). PLR (HR 1.54/log-unit, 95% CI 1.12-2.12) was the only prognostic factor associated with FFS after adjusting for CNS and ≥ 2 distant metastatic sites. CONCLUSION: Older age, increased PLR, and ALP were identified as poor prognostic factors and ER positivity as a favorable prognostic factor for OS after adjusting for the presence of CNS metastasis and the presence of number of ≥ 2 distant metastatic sites. Increased PLR was a poor prognostic factor for both OS and FFS, and warrants further investigation into its prognostic ability amongst patients with HER2-positive metastatic breast cancer.


Subject(s)
Blood Platelets , Breast Neoplasms/drug therapy , Lymphocytes , Neoplasms, Second Primary/drug therapy , Receptor, ErbB-2/blood , Adult , Aged , Breast Neoplasms/blood , Breast Neoplasms/epidemiology , Breast Neoplasms/pathology , Disease-Free Survival , Female , Humans , Kaplan-Meier Estimate , Middle Aged , Neoplasm Metastasis , Neoplasms, Second Primary/blood , Neoplasms, Second Primary/epidemiology , Neoplasms, Second Primary/pathology , Ontario , Prognosis , Proportional Hazards Models , Trastuzumab/administration & dosage , Trastuzumab/adverse effects
6.
Mucosal Immunol ; 11(3): 703-715, 2018 05.
Article in English | MEDLINE | ID: mdl-29139475

ABSTRACT

Retinoic acid (RA), a dietary vitamin A metabolite, is crucial in maintaining intestinal homeostasis. RA acts on intestinal leukocytes to modulate their lineage commitment and function. Although the role of RA has been characterized in immune cells, whether intestinal epithelial cells (IECs) rely on RA signaling to exert their immune-regulatory function has not been examined. Here we demonstrate that lack of RA receptor α (RARα) signaling in IECs results in deregulated epithelial lineage specification, leading to increased numbers of goblet cells and Paneth cells. Mechanistically, lack of RARα resulted in increased KLF4+ goblet cell precursors in the distal bowel, whereas RA treatment inhibited klf4 expression and goblet cell differentiation in zebrafish. These changes in secretory cells are associated with increased Reg3g, reduced luminal bacterial detection, and an underdeveloped intestinal immune system, as evidenced by an almost complete absence of lymphoid follicles and gut resident mononuclear phagocytes. This underdeveloped intestinal immune system shows a decreased ability to clear infection with Citrobacter rodentium. Collectively, our findings indicate that epithelial cell-intrinsic RARα signaling is critical to the global development of the intestinal immune system.


Subject(s)
Citrobacter rodentium/immunology , Enterobacteriaceae Infections/immunology , Goblet Cells/physiology , Intestinal Mucosa/physiology , Mononuclear Phagocyte System , Retinoic Acid Receptor alpha/metabolism , Tretinoin/metabolism , Animals , Cell Differentiation , Cells, Cultured , Homeostasis , Kruppel-Like Factor 4 , Kruppel-Like Transcription Factors/metabolism , Mice , Mice, Inbred C57BL , Mice, Knockout , Pancreatitis-Associated Proteins/genetics , Pancreatitis-Associated Proteins/metabolism , Retinoic Acid Receptor alpha/genetics , Signal Transduction , Zebrafish
7.
Curr Oncol ; 23(Suppl 1): S23-31, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26985143

ABSTRACT

BACKGROUND: Obtaining accurate histopathologic detail for breast lumpectomy specimens is challenging because of sampling and loss of three-dimensional conformational features with conventional processing. The whole-mount (wm) technique is a novel method of serial pathologic sectioning designed to optimize cross-sectional visualization of resected specimens and determination of margin status. METHODS: Using a Markov chain cohort simulation cost-effectiveness model, we compared conventional processing with wm technique for breast lumpectomies. Cost-effectiveness was evaluated from the perspective of the Canadian health care system and compared using incremental cost-effectiveness ratios (icers) for cost per quality-adjusted life-year (qaly) over a 10-year time horizon. Deterministic and probabilistic sensitivity analyses were performed to test the robustness of the model with willingness-to-pay (wtp) thresholds of $0-$100,000. Costs are reported in adjusted 2014 Canadian dollars, discounted at a rate of 3%. RESULTS: Compared with conventional processing, wm processing is more costly ($19,989 vs. $18,427) but generates 0.03 more qalys over 10 years. The icer is $45,414, indicating that this additional amount is required for each additional qaly obtained. The model was robust to all variance in parameters, with the prevalence of positive margins accounting for most of the model's variability. CONCLUSIONS: After a wtp threshold of $45,414, wm processing becomes cost-effective and ultimately generates fewer recurrences and marginally more qalys over time. Excellent baseline outcomes for the current treatment of breast cancer mean that incremental differences in survival are small. However, the overall benefit of the wm technique should be considered in the context of achieving improved accuracy and not just enhancements in clinical effectiveness.

8.
Curr Oncol ; 22(3): 174-6, 2015 Jun.
Article in English | MEDLINE | ID: mdl-26089713
9.
Eur Psychiatry ; 30(2): 329-33, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25282362

ABSTRACT

OBJECTIVE: The purpose of the current study was to assess the associations of illness perception-related variables with satisfaction with life (SwL) among adolescents with mental disorders. METHODS: Insight into mental disorder (SAI-E), Internalized stigma of mental illness (ISMI) and Multidimensional Students' Life Satisfaction Scale (MSLSS) were administrated to 30 adolescent patients. Adapted version for parents of the SAI-E was also administrated to 37 of their parents. RESULTS: Significant positive correlations were found between insight into the illness, self-stigma and parental insight. Insight and self-stigma were significantly negatively related to the total score of SwL and few of its dimensions while parental insight was significantly associated only with the SwL dimensions of school and self. Regression models revealed main negative effects of insight and self-stigma on SwL and no interaction effect. CONCLUSIONS: The possible independent contribution of insight and self-stigma to SwL should be addressed in interventions designed for family and adolescents coping with mental illness. Special attention should be given to the possible negative implications that insight possesses. In lack of support of the moderation role of self-stigma, reported in studies among adults with mental illness, future studies should trace other variables in order to further understand the insight paradox among adolescents.


Subject(s)
Mental Disorders/psychology , Parents , Personal Satisfaction , Social Perception , Social Stigma , Adaptation, Psychological , Adolescent , Adult , Awareness , Female , Humans , Judgment , Male , Middle Aged , Parents/psychology , Problem Solving , Self Concept
10.
Phys Med Biol ; 59(21): 6621-35, 2014 Nov 07.
Article in English | MEDLINE | ID: mdl-25325670

ABSTRACT

A reader study was conducted to tune the parameters of an observer model used to predict the detectability index (dʹ ) of test objects as a task-based quality control (QC) metric for digital mammography. A simple test phantom was imaged to measure the model parameters, namely, noise power spectrum,modulation transfer function and test-object contrast. These are then used ina non-prewhitening observer model, incorporating an eye-filter and internal noise, to predict dʹ. The model was tuned by measuring dʹ of discs in a four-alternative forced choice reader study. For each disc diameter, dʹ was used to estimate the threshold thicknesses for detectability. Data were obtained for six types of digital mammography systems using varying detector technologies and x-ray spectra. A strong correlation was found between measured and modeled values of dʹ, with Pearson correlation coefficient of 0.96. Repeated measurements from separate images of the test phantom show an average coefficient of variation in dʹ for different systems between 0.07 and 0.10. Standard deviations in the threshold thickness ranged between 0.001 and 0.017 mm. The model is robust and the results are relatively system independent, suggesting that observer model dʹ shows promise as a cross platform QC metric for digital mammography.


Subject(s)
Breast/pathology , Mammography/methods , Mammography/standards , Models, Theoretical , Phantoms, Imaging , Quality Control , Radiographic Image Enhancement/methods , Radiographic Image Enhancement/standards , Female , Humans , X-Rays
11.
Cell Death Differ ; 21(6): 854-63, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24510127

ABSTRACT

TAZ, a transcriptional modulator, has a key role in cell proliferation, differentiation and stem cell self-renewal. TAZ activity is regulated by several signalling pathways, including Hippo, GPCR and Wnt signalling, but the regulatory mechanisms of TAZ activation are not yet clearly understood. In this report, we show that TAZ is regulated by canonical Wnt signalling during osteogenic differentiation. Wnt3a increases TAZ expression and an inhibitor of GSK3ß, a downstream effector of Wnt signalling, induces TAZ. Wnt3a facilitates the dephosphorylation of TAZ, which stabilises TAZ and prevents it from binding 14-3-3 proteins, thus inducing the nuclear localisation of TAZ. Dephosphorylation of TAZ occurs via PP1A, and depletion of PP1A blocks Wnt3a-induced TAZ stabilisation. Wnt3a-induced TAZ activates osteoblastic differentiation and siRNA-induced TAZ depletion decreases Wnt3a-induced osteoblast differentiation. Taken together, these results show that TAZ mediates Wnt3a-stimulated osteogenic differentiation through PP1A, suggesting that the Wnt signal regulates the Hippo pathway.


Subject(s)
Osteogenesis/genetics , Signal Transduction/genetics , Transcription Factors/genetics , Wnt3A Protein/metabolism , 14-3-3 Proteins/genetics , Acyltransferases , Animals , Cell Differentiation/genetics , Cell Proliferation/genetics , Gene Expression Regulation, Developmental , Hippo Signaling Pathway , Humans , Mice , NIH 3T3 Cells , Osteoblasts/metabolism , Protein Serine-Threonine Kinases/genetics , Transcription Factors/metabolism , Wnt3A Protein/genetics
12.
Phys Med Biol ; 57(22): 7443-57, 2012 Nov 21.
Article in English | MEDLINE | ID: mdl-23093428

ABSTRACT

In this paper we present the results of an automated and entirely reproducible algorithm that estimates the breast volume, dense tissue volume and the volumetric breast density from digital mammograms. The algorithm was applied to 55, 087 digital images (CC view only) from 15 351 individual women, acquired between 2008 and 2011 at the Sunnybrook Health Sciences Centre in Toronto, Canada. The algorithm is based on a prior calibration of the digital image signal versus tissue thickness and composition, and the thickness of the compressed breast is estimated using an empirical model that corrects the thickness readout of the mammography system as a function of compression force. The mean volumetric density and breast volumes for our study group were 30% and 687 cm(3), respectively. The left and right volumetric density and breast volume were strongly correlated, with a Pearson correlation of 0.92 and 0.91, respectively. The volumetric density decreased from 45% to 25% as age increased from 35 to 75 years, with an increase to 30% at 80 years. For a given woman, the volumetric density decreased at an average rate of -2 density percentage points per year while the breast volume increased by 2% per year.


Subject(s)
Breast/anatomy & histology , Breast/cytology , Mammography/methods , Radiographic Image Enhancement/methods , Aged , Aging , Algorithms , Female , Humans , Middle Aged , Organ Size , Phantoms, Imaging
13.
Br J Cancer ; 107(1): 24-30, 2012 Jun 26.
Article in English | MEDLINE | ID: mdl-22588560

ABSTRACT

BACKGROUND: The addition of breast magnetic resonance imaging (MRI) to screening mammography for women with BRCA mutations significantly increases sensitivity, but there is little data on clinical outcomes. We report screening performance, cancer stage, distant recurrence rate, and breast cancer-specific mortality in our screening study. METHODS: From 1997 to 2009, 496 women aged 25 to 65 years with a known BRCA1/2 mutation, of whom 380 had no previous cancer history, were enrolled in a prospective screening trial that included annual MRI and mammography. RESULTS: In 1847 screening rounds, 57 cancers were identified (53 screen-detected, 1 interval, and 3 incidental at prophylactic mastectomy), of which 37 (65%) were invasive. Sensitivity of MRI vs mammography was 86% vs 19% over the entire study period (P<0.0001), but was 74% vs 35% from 1997 to 2002 (P=0.02) and 94% vs 9% from 2003 to 2009 (P<0.0001), respectively. The relative sensitivities of MRI and mammography did not differ by mutation, age, or invasive vs non-invasive disease. Of the incident cancers, 97% were Stage 0 or 1. Of 28 previously unaffected women diagnosed with invasive cancer, 1 BRCA1 mutation carrier died following relapse of a 3 cm, node-positive breast cancer diagnosed on her first screen at age 48 (annual breast cancer mortality rate=0.5%). Three patients died of other causes. None of the 24 survivors has had a distant recurrence at a median follow-up of 8.4 years since diagnosis. CONCLUSION: Magnetic resonance imaging surveillance of women with BRCA1/2 mutations will detect the majority of breast cancers at a very early stage. The absence of distant recurrences of incident cancers to date is encouraging. However, longer follow-up is needed to confirm the safety of breast surveillance.


Subject(s)
Breast Neoplasms/diagnosis , Genes, BRCA1 , Genes, BRCA2 , Magnetic Resonance Imaging , Adult , Breast Neoplasms/genetics , Breast Neoplasms/mortality , Breast Neoplasms/pathology , Early Detection of Cancer , Female , Humans , Mammography , Middle Aged , Mutation , Sensitivity and Specificity
14.
Int J Breast Cancer ; 2012: 691205, 2012.
Article in English | MEDLINE | ID: mdl-23320179

ABSTRACT

Tumour size, most commonly measured by maximum linear extent, remains a strong predictor of survival in breast cancer. Tumour volume, proportional to the number of tumour cells, may be a more accurate surrogate for size. We describe a novel "3D pathology volumetric technique" for lumpectomies and compare it with 2D measurements. Volume renderings and total tumour volume are computed from digitized whole-mount serial sections using custom software tools. Results are presented for two lumpectomy specimens selected for tumour features which may challenge accurate measurement of tumour burden with conventional, sampling-based pathology: (1) an infiltrative pattern admixed with normal breast elements; (2) a localized invasive mass separated from the in situ component by benign tissue. Spatial relationships between key features (tumour foci, close or involved margins) are clearly visualized in volume renderings. Invasive tumour burden can be underestimated using conventional pathology, compared to the volumetric technique (infiltrative pattern: 30% underestimation; localized mass: 3% underestimation for invasive tumour, 44% for in situ component). Tumour volume approximated from 2D measurements (i.e., maximum linear extent), assuming elliptical geometry, was seen to overestimate volume compared to the 3D volumetric calculation (by a factor of 7x for the infiltrative pattern; 1.5x for the localized invasive mass).

15.
Med Phys ; 39(6Part21): 3871, 2012 Jun.
Article in English | MEDLINE | ID: mdl-28518256

ABSTRACT

PURPOSE: To describe the current state of dual energy contrast-enhanced digital mammography, to discuss those aspects of its operation that require evaluation or monitoring and to propose elements of a program for quality assurance of such systems. METHODS: The principles of dual-energy contrast imaging will be discussed and tools and techniques for assessment of performance will be described. RESULTS: Many of the elements affecting image quality and dose performance in digital mammography (eg noise, system linearity, consistency of x-ray output and detector performance, artifacts) remain important. In addition, the ability to register images can influence the resultant image quality. The maintenance of breast compression thickness during the imaging procedure and calibration of the system to allow quantification of iodine in the breast represent new challenges to quality assurance. CONCLUSION: CESM provides a means of acquiring new information regarding tumor angiogenesis and may reveal some cancers that will not be detectable on digital mammography. It may also better demonstrate the extent of disease. The medical physicist must understand the dependence of image quality on physical factors. Implementation of a relevant QA program will be required if the promise of this new modality is to be delivered.

16.
Dentomaxillofac Radiol ; 40(6): 362-8, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21831976

ABSTRACT

OBJECTIVES: The assessment of image quality is a crucial step in the development of a new imaging protocol. Having proposed and reported on a preliminary protocol for sialography using cone beam CT (CBCT), the purpose of this study was to further optimize this protocol by maximizing the image signal difference-to-noise ratio (SDNR) and to relate these new data to previously published dosimetric data for CBCT sialography. METHODS: An imaging phantom was constructed using samples with different concentrations of iodine and a water-immersed mandible. The CB MercuRay (Hitachi Medical Systems, Tokyo, Japan) was used to image the phantom using different peak kilovoltage (kVp) and milliamperage (mA) settings. SDNR was then calculated using the raw images based on mean pixel values (MPV) measured in selected regions of interest (ROI). Finally, a figure of merit (FOM) was calculated to examine the trade-off between image SDNR and effective radiation dose. RESULTS: The SDNR demonstrated an expected increase as the kVp increased from 60 to 120. Also, images made with the higher mA setting (15) had greater SDNR. The iodine concentration also influenced the image quality such that SDNR increased with increased amounts of iodine. The calculated FOM was greatest for the technique using 80 kVp, with equivalent results for 10 mA and 15 mA. CONCLUSION: An optimized protocol for CBCT sialography using CB MercuRay entails a 6 inch field of view with 80 kVp and 10 mA.


Subject(s)
Cone-Beam Computed Tomography/methods , Sialography/methods , Artifacts , Cadaver , Contrast Media , Humans , Iodine , Mandible/diagnostic imaging , Phantoms, Imaging , Radiometry
17.
Breast Cancer Res Treat ; 126(2): 453-61, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21221773

ABSTRACT

We hypothesized that exemestane (EXE) would reduce mammographic breast density and have unique effects on biomarkers of bone and lipid metabolism. Healthy postmenopausal women were randomized to EXE (25 mg daily) or placebo (PLAC) for 12 months and followed for a total of 24 months. The primary endpoint was change in percent breast density (PD) between the baseline and 12-month mammograms and secondary endpoints were changes in serum lipid levels, bone biomarkers, and bone mineral density (BMD). Ninety-eight women were randomized (49 to EXE; 49 to PLAC) and 65 had PD data at baseline and 12 months. Among women treated with EXE, PD was not significantly changed from baseline at 6, 12, or 24 months and was not different from PLAC. EXE was associated with significant percentage increase from baseline in N-telopeptide at 12 months compared with PLAC. No differences in percent change from baseline in BMD (lumbar spine and femoral neck) were observed between EXE and PLAC at either 12 or 24 months. Patients on EXE had a significantly larger percent decrease in total cholesterol than in the PLAC arm at 6 months and in HDL cholesterol at 3, 6, and 12 months. No significant differences in percent change in LDL or triglycerides were noted at any time point between the two treatment arms. EXE administered for 1 year to healthy postmenopausal women did not result in significant changes in mammographic density. A reversible increase in the bone resorption marker N-telopeptide without significant change in bone specific alkaline phosphatase or BMD during the 12 months treatment period and 1 year later was noted. Changes in lipid parameters on this trial were modest and reversible.


Subject(s)
Androstadienes/therapeutic use , Aromatase Inhibitors/therapeutic use , Bone Density/drug effects , Bone and Bones/metabolism , Breast/drug effects , Lipid Metabolism/drug effects , Lipids/blood , Postmenopause/metabolism , Alkaline Phosphatase/blood , Breast Neoplasms/prevention & control , Collagen Type I/urine , Double-Blind Method , Female , Humans , Mammography , Middle Aged , Peptides/urine
18.
Int J Obes (Lond) ; 35(3): 427-35, 2011 Mar.
Article in English | MEDLINE | ID: mdl-20820172

ABSTRACT

OBJECTIVE: We examined the effects of an aerobic exercise intervention on adiposity outcomes that may be involved in the association between physical activity and breast cancer risk. DESIGN: This study was a two-centre, two-armed, randomized controlled trial. The 1-year-long exercise intervention included 45 min of moderate-to-vigorous aerobic exercise five times per week, with at least three of the sessions being facility based. The control group was asked not to change their activity and both groups were asked not to change their diet. SUBJECTS: A total of 320 postmenopausal, sedentary, normal weight-to-obese women aged 50-74 years who were cancer-free, nondiabetic and nonhormone replacement therapy users were included in this study. MEASUREMENTS: Anthropometric measurements of height, weight and waist and hip circumferences; dual energy X-ray absorptiometry measurements of total body fat; and computerized tomography measurements of abdominal adiposity were carried out. RESULTS: Women in the exercise group exercised a mean of 3.6 days (s.d.=1.3) per week and 178.5 min (s.d.=76.1) per week. Changes in all measures of adiposity favored exercisers relative to controls (P<0.001). The mean difference between groups was: -1.8 kg for body weight; -2.0 kg for total body fat; -14.9 cm(2) for intra-abdominal fat area; and -24.1 cm(2) for subcutaneous abdominal fat area. A linear trend of greater body fat loss with increasing volume of exercise was also observed. CONCLUSION: A 1-year aerobic exercise program consistent with current public health guidelines resulted in reduced adiposity levels in previously sedentary postmenopausal women at higher risk of breast cancer.


Subject(s)
Adiposity/physiology , Exercise/physiology , Postmenopause , Absorptiometry, Photon , Aged , Female , Health Promotion , Humans , Middle Aged , Motor Activity , Postmenopause/physiology , Risk Factors , Treatment Outcome
19.
Dentomaxillofac Radiol ; 39(5): 257-63, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20587648

ABSTRACT

OBJECTIVES: As a first step in developing a protocol for multidimensional sialography using cone beam CT (CBCT), the objective of this study was to compare the effective radiation doses from sialography of the parotid and submandibular glands using plain radiography and CBCT. METHODS: The effective doses were calculated from dose measurements made at 25 selected locations in the head and neck of a radiation analogue dosimeter (RANDO) phantom, using International Commission on Radiological Protection 2007 tissue weighting factors. RESULTS: The effective dose (E) changed in relationship to changes in CBCT field of view (FOV), peak kilovoltage (kVp) and milliamperage (mA). Specifically, E decreased from a maximum of 932 microSv (30 cm FOV, 120 kVp, 15 mA) to 60 microSv (15 cm FOV, 80 kVp, 10 mA) for a parotid gland study and to 148 microSv (15 cm FOV, 80 kVp, 10 mA) for a submandibular study. The collective series of plain radiographs made during sialography of the parotid and submandibular glands yielded effective doses of 65 microSv and 156 microSv, respectively. The plain parotid gland series included one panoramic, two anterior-posterior skull and four lateral skull radiographs, whereas the submandibular gland series included one panoramic, one standard mandibular occlusal and four lateral skull radiographs. CONCLUSION: The effective doses from CBCT examinations centred on the parotid and submandibular glands were similar to those calculated for plain radiograph sialography when a 15 cm FOV was chosen in combination with exposure conditions of 80 kVp and 10 mA.


Subject(s)
Cone-Beam Computed Tomography/methods , Radiation Dosage , Sialography/methods , Bone Marrow/radiation effects , Brain/radiation effects , Humans , Imaging, Three-Dimensional/methods , Mandible/diagnostic imaging , Parotid Gland/diagnostic imaging , Parotid Gland/radiation effects , Phantoms, Imaging , Radiographic Image Enhancement/methods , Radiography, Panoramic/methods , Relative Biological Effectiveness , Skull/diagnostic imaging , Submandibular Gland/diagnostic imaging , Submandibular Gland/radiation effects , Thermoluminescent Dosimetry/instrumentation , Thyroid Gland/radiation effects
20.
Phys Med Biol ; 55(11): 3027-44, 2010 Jun 07.
Article in English | MEDLINE | ID: mdl-20463377

ABSTRACT

The purpose of this study was to evaluate the performance of an algorithm used to measure the volumetric breast density (VBD) from digital mammograms. The algorithm is based on the calibration of the detector signal versus the thickness and composition of breast-equivalent phantoms. The baseline error in the density from the algorithm was found to be 1.25 +/- 2.3% VBD units (PVBD) when tested against a set of calibration phantoms, of thicknesses 3-8 cm, with compositions equivalent to fibroglandular content (breast density) between 0% and 100% and under x-ray beams between 26 kVp and 32 kVp with a Rh/Rh anode/filter. The algorithm was also tested against images from a dedicated breast computed tomography (CT) scanner acquired on 26 volunteers. The CT images were segmented into regions representing adipose, fibroglandular and skin tissues, and then deformed using a finite-element algorithm to simulate the effects of compression in mammography. The mean volume, VBD and thickness of the compressed breast for these deformed images were respectively 558 cm(3), 23.6% and 62 mm. The displaced CT images were then used to generate simulated digital mammograms, considering the effects of the polychromatic x-ray spectrum, the primary and scattered energy transmitted through the breast, the anti-scatter grid and the detector efficiency. The simulated mammograms were analyzed with the VBD algorithm and compared with the deformed CT volumes. With the Rh/Rh anode filter, the root mean square difference between the VBD from CT and from the algorithm was 2.6 PVBD, and a linear regression between the two gave a slope of 0.992 with an intercept of -1.4 PVBD and a correlation with R(2) = 0.963. The results with the Mo/Mo and Mo/Rh anode/filter were similar.


Subject(s)
Breast/pathology , Image Processing, Computer-Assisted/methods , Mammography/methods , Adipose Tissue/pathology , Algorithms , Calibration , Female , Finite Element Analysis , Humans , Models, Statistical , Reproducibility of Results , Skin/pathology , Software , Tomography, X-Ray Computed/methods , X-Rays
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