Publications by authors named "Frost M"

Introduction: The use of image-derived arterial input functions (IDAIF) for the dynamic quantification of bone metabolism using 18F-fluoride positron emission tomography 18F-PET is an attractive alternative to direct arterial blood sampling.

Purposes: (a) To validate a method for obtaining the IDAIF by imaging the femoral artery against a method for deriving the IDAIF at the aorta that was previously validated against direct arterial sampling. (b) To compare the accuracy of bone plasma clearance measurements (Ki) at the total hip site obtained using the femoral artery IDAIF against Ki values at the same site obtained using the aorta IDAIF.

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Purpose: The study aims to identify Minnesota nurses' perceptions regarding nursing diagnoses and to examine how these perceptions have changed over time.

Methods: Five hundred sixty-four out of 2,000 randomly selected registered nurses in Minnesota responded to the Perceptions of Nursing Diagnosis Survey.

Findings: Nurses have neutral to slightly negative perceptions of nursing diagnoses.

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Regions of turbulence downstream of bioprosthetic heart valves may cause damage to blood components, vessel wall as well as to aortic valve leaflets. Stentless aortic heart valves are known to posses several hemodynamic benefits such as larger effective orifice areas, lower aortic transvalvular pressure difference and faster left ventricular mass regression compared with their stented counterpart. Whether this is reflected by diminished turbulence formation, remains to be shown.

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Quantitative radionuclide imaging using (18)F-fluoride positron emission tomography (18F-PET) or (99m)Tc-methylene diphosphonate ((99m)Tc-MDP) bone scans provides a novel tool for studying regional and whole skeleton bone turnover that complements the information provided by biochemical markers. Radionuclide bone scans can be quantified by measuring either tracer uptake or, if blood sampling is performed, bone plasma clearance. This study examines whether these two methods provide equivalent information about bone turnover.

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Background: Solid pseudopapillary epithelial neoplasms (SPENs) of the pancreas are rare but curable tumours that have a low-grade malignant potential and occur almost exclusively in young women, with an excellent prognosis after complete resection. This study examines the clinicopathological characteristics of these tumours and evaluates the role of surgery in relation to their size and location.

Study Design: We reviewed the pre-, intra- and postoperative data on 21 patients with SPENs who underwent resection during a 30-year period.

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Studies of bone remodeling using bone biopsy and biochemical markers of bone turnover play an important role in research studies to investigate the effect of new osteoporosis treatments on bone quality. Quantitative radionuclide imaging using either positron emission tomography with fluorine-18 sodium fluoride or gamma camera studies with technetium-99m methylene diphosphonate provides a novel tool for studying bone metabolism that complements conventional methods, such as bone turnover markers (BTMs). Unlike BTMs, which measure the integrated response to treatment across the whole skeleton, radionuclide imaging can distinguish the changes occurring at sites of particular clinical interest, such as the spine or proximal femur.

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Dense aggregations of tube-worms can stabilize sediments and generate oases for benthic communities that are different and often more diverse and abundant than those of the surroundings. If these features are to qualify as biogenic reefs under nature-conservation legislation such as the EC Habitats Directive, a level of stability and longevity is desirable aside from physical and biological attributes. Lanice conchilega (Pallas, 1766) is widely distributed around the European coast and aggregations of this tube-dwelling polychaete are known to have a positive effect on the biodiversity of associated species in inter- and sub-tidal areas.

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Teriparatide increases skeletal mass, bone turnover markers, and bone strength, but local effects on bone tissue may vary between skeletal sites. We used positron emission tomography (PET) to study (18)F-fluoride plasma clearance (K(i)) at the spine and standardized uptake values (SUVs) at the spine, pelvis, total hip, and femoral shaft in 18 postmenopausal women with osteoporosis. Subjects underwent a 1-hour dynamic scan of the lumbar spine and a 10-minute static scan of the pelvis and femurs at baseline and after 6 months of treatment with 20 µg/day teriparatide.

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Purpose: To increase our understanding of the mechanisms that remodel the sclera during the development of lens-induced myopia, when the sclera responds to putative "go" signals of retinal origin, and during recovery from lens-induced myopia, when the sclera responds to retinally-derived "stop" signals.

Methods: Seven groups of tree shrews were used to examine mRNA levels during minus lens compensation and recovery. Starting 24 days after eye opening (days of visual experience [VE]) lens compensation animals wore a monocular -5D lens for 1, 4, or 11 days.

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Objectives: Our aim was to examine the relationship of arterial stiffness to measures of atherosclerosis, arterial calcification, and bone mineral density (BMD); the heritability of these measures; and the degree to which they are explained by common genetic influences.

Background: Arterial stiffening relates to arterial calcification, but this association could result from coexistent atherosclerosis. A reciprocal relationship between arterial stiffening/calcification and BMD could explain the association between cardiovascular morbidity and osteoporosis.

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Summary: Risk factors for fractures were assessed in a random sample of 4,696 elderly men followed for 5.4 years. Results highlighted the importance of assessment of falls and dizziness as well as novel risk factors including frequent urination and erectile dysfunction.

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Objectives: (i) To validate two new image-based methods for finding the plasma arterial input function (AIF) and evaluate the performance of these and two similar techniques against arterial sampling. (ii) To evaluate the performance of all four image-derived AIF (IDAIF) methods against arterial sampling for measuring the F plasma clearance (Ki) to the lumbar spine.

Methods: Eight healthy postmenopausal women had a F-fluoride positron emission tomography scan of the lumbar spine.

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Unlabelled: Osteoporosis in men is underdiagnosed. The use of dual-emission X-ray absorptiometry (DXA) was evaluated in almost 5,000 men aged 60-74 years. DXA was infrequent, despite the presence of multiple risk factors for osteoporosis and a high FRAX score.

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Patients with an activation mutation of the Lrp5 gene exhibit high bone mass (HBM). Limited information is available regarding compartment-specific changes in bone. The relationship between the phenotype and serum serotonin is not well documented.

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Intrahospital transportation can be complicated and hazardous. Mobile computerized tomography (CT) of the head performed at the neurointensive care unit is a new technique that minimizes the need for transportation of unstable patients. Even small changes in physiological parameters can be detrimental for these patients and cause secondary injury and thus affect their prognoses.

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Epidermal growth factor (EGF), hepatocyte growth factor (HGF), and vascular endothelial growth factor (VEGF) regulate angiogenesis and cell growth in the developing brain. EGF, HGF, and VEGF modulate the activity of the mammalian target of rapamycin (mTOR) cascade, a pathway regulating cell growth that is aberrantly activated in tuberous sclerosis complex (TSC). We hypothesized that expression of EGF, HGF, VEGF, and their receptors EGFR, c-Met, and Flt-1, respectively, would be altered in TSC.

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Estrogen receptor (ER) is expressed in normal and malignant breast epithelium, and expression levels have been found to increase with age in normal breast epithelium but not in atypical hyperplasia (AH) and carcinoma in situ. Here we assess ER expression in AH and its association with later breast cancer. ER expression was assessed immunohistochemically in archival sections from 246 women with AH who had open benign breast biopsy from 1967 to 1991.

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Background: Lobular involution, or age-related atrophy of breast lobules, is inversely associated with breast cancer risk, and mammographic breast density (MBD) is positively associated with breast cancer risk.

Methods: To evaluate whether lobular involution and MBD are independently associated with breast cancer risk in women with benign breast disease, we performed a nested cohort study among women (n = 2666) with benign breast disease diagnosed at Mayo Clinic between January 1, 1985, and December 31, 1991 and a mammogram available within 6 months of the diagnosis. Women were followed up for an average of 13.

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Objective: The goal of this paper is to discuss cancer-related fatigue (CRF) and address issues related to the investigation into potential biological and genetic causal mechanisms. The objectives are to: (1) describe CRF as a component of quality of life (QOL); (2) address measurement issues that have slowed progress toward an understanding of mechanisms underlying this symptom; (3) review biological pathways and genetic approaches that have promise for the exploration of causal mechanisms of CRF; and (4) offer directions for future research.

Methods: Review, synthesis, and interpretation of the literature.

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Purpose: Neighborhood features have been linked with adult mental-health problems, particularly depression. A recent comprehensive review indicated structural neighborhood features derived from data sources such as the census may be less important predictors of mental health problems than social processes but that most studies lack multiple neighborhood measures. The aim of the study is to investigate relations between multiple neighborhood factors (observations, interviewer ratings, UK Census data) and maternal mental-health problems.

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Background: The aim of this study was to investigate whether contralateral prophylactic mastectomy (CPM) in addition to therapeutic mastectomy (TM) is associated with a survival advantage in high-risk women with breast cancer.

Methods: A total of 385 women with stage I or II breast cancer and a family history of breast cancer who underwent TM and CPM between 1971 and 1993 were evaluated and compared to 385 patients matched on age at diagnosis, tumor stage, nodal status, and year of diagnosis who underwent TM-only. Contralateral breast cancer (CBC) events and survival outcomes were compared.

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Background And Aim Of The Study: Stiffening of the aortic root may entail asynchronous aortic leaflet movement, and result in enhanced flexion-stress in specific areas of the cusps. As stentless prostheses are more flexible than their stented counterparts, they are more likely to exhibit physiologic leaflet movements. The study aim was to compare leaflet movement dynamics in stented versus non-stented aortic valves implanted in pigs.

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Uncertainties exist regarding whether FGF-23 production is influenced by PTH and its involvement in bone formation. We evaluated FGF-23 response and its relation to changes in biomarkers of bone formation following intermittent PTH treatment. Twenty-seven women with a mean [SD] age of 75.

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