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Nodular lymphoid hyperplasia is a rare, benign, lymphoproliferative disease usually found in the gastrointestinal tract. It has never been reported in the sinuses. We present an unusual case of pulmonary nodular lymphoid hyperplasia with locally invasive sinus involvement and describe the CT, MRI and positron emission tomography findings.

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Significant gaps persist in our understanding of chondrocyte biology. We do not know when, how, or even whether these cells are replenished throughout the normal, human life span. We are taught that as much as 90% of the cartilage is "metabolically inert" interterritorial matrix, but we do not know how this substance is regularly replaced (as it is known to be) by the distant chondrocytes, We recognise that the "tidemark" is the most conspicuous histological feature within cartilage, but we do not understand why that layer stains with haematoxylin or what that may imply for the biology of the tissue. These, and other issues may be clarified if the lifetime of each chondrocyte begins as a mesenchymal stem cell at the articular margin, plays out over years on an arcing trajectory along collagenous guidelines, and ends as an extracellular deposit of intracellular remains at the interface between uncalcified and calcified cartilage. This hypothesis is presented here, and some of its potential implications are considered.

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BACKGROUND: Nonhuman primates develop the characteristic lesions of osteoarthritis, making them attractive biomedical models for the study of environmental factors, such as diet, which may influence the progress of the condition. METHODS AND MATERIALS: We used ELISA assays of potential markers of osteoarthritis which were developed for use in humans to see if we could determined the presence of immunoreactivity in two nonhuman primate genera - Macaca (macaque monkeys) and Saimiri (squirrel monkeys). RESULTS: Inter-generic differences were significant for most markers. Three markers (bone alkaline phosphatase, hyaluronin and YKL-40) were outside the human range and two markers (laminin and C2C) did not yield useful results because they were off-scale high. CONCLUSION: Our results indicate that most of the ELISA assays designed for use with human serum can be used in nonhuman primates. The highly significant differences we observed between the sera of Macaca and Saimiri, suggest that further examination is warranted.

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An earlier localization ROC (LROC) study that found attenuation correction (AC) degraded the detection of solitary pulmonary nodules (SPN) in hybrid SPECT lung images had several potential shortcomings related to the simulation methods. We sought to address these issues with a revised LROC study. Clinical Tc-99m NeoTect scans acquired with a simultaneous transmission-emission protocol defined the normal cases in a single-slice LROC study. Abnormal cases contained a simulated 1-cm lung lesion. Four rescaled-block-iterative EM (RBI) reconstruction strategies applied: 1) AC, scatter correction (SC), and resolution compensation (RC); 2) AC only; 3) RC only; and 4) no corrections (NC). Images from these strategies underwent 3D Gaussian post-smoothing. Performances were defined by the average area under the LROC curve obtained from three human observers. The strategy ranking in order of decreasing performance was: 1) RBI with RC; 2) RBI with all corrections; 3) RBI with AC; and 4) RBI with no corrections. A multireader-multicase (MRMC) analysis only found significant patient and patient-strategy effects. The conflicting results concerning AC from this study and the previous one may revolve around lesion masking effects, which, by design, were not a factor in the current study.

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BACKGROUND: Tumour necrosis factor alpha (TNF alpha) antagonists are effective for the treatment of rheumatoid arthritis (RA), but concerns remain about the safety of these agents in the presence of chronic infections, including hepatitis C virus (HCV) infection. OBJECTIVE: To examine the influence of treatment with TNF alpha antagonists on levels of HCV viraemia and serum transaminases in patients with RA and HCV. METHODS: In a retrospective survey the course of 16 HCV infected patients with RA who had received the TNF alpha antagonists etanercept or infliximab was analysed. Eight additional patients with RA and HCV were also enrolled into a three month prospective trial of etanercept. Serum concentrations of albumin, alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase, and HCV were followed. RESULTS: Viraemia was measured in 22 patients receiving a TNF alpha antagonist at the start of treatment and after 1-34 months (median 9 months follow up). Twenty four patients had serial tests of liver related enzymes and albumin. None of the differences between liver related tests at baseline and at follow up achieved significance (p>0.05). Similarly, the mean HCV measurement at 1-3, 4-6, 7-12, and 13-34 months did not differ significantly from baseline (p>0.05). CONCLUSION: In this study, liver related blood tests and HCV viral load measurements did not change substantially. These findings suggest that TNF alpha antagonists merit further study for the treatment of RA in HCV infected patients. Larger and longer term studies are still needed.

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Recombinant human TSH (rhTSH), usually given as 0.9-mg doses im on 2 successive days, increases serum thyroglobulin (Tg) and radioactive iodine uptake (RAIU) in residual thyroid tissue in patients with thyroid cancer. We previously reported that a single, relatively low dose of rhTSH (0.1 mg im) is a potent stimulator of T(4), T(3), and Tg secretion in normal subjects. The present study describes the effects of higher doses of rhTSH on thyroid hormone and Tg secretion. Six normal subjects for each dose group, having no evidence of thyroid disease, received either 0.3 or 0.9 mg rhTSH by im injection. Serum TSH, T(4), T(3), and Tg concentrations were measured at 2, 4, and 8 h and 1, 2, 3, 4, and 7 days after rhTSH administration. The peak serum TSH concentrations were 82 +/- 18 and 277 +/- 89 mU/L, respectively, for the 0.3- and 0.9-mg doses of rhTSH. Serum T(4), T(3), and Tg concentrations increased significantly in subjects receiving 0.3 and 0.9 mg rhTSH, with significant increases in T(4) and T(3) being observed before significant increases in serum TG: Peak concentrations of serum T(4), T(3), and Tg, after 0.3 mg rhTSH administration, were 100 +/- 19, 131 +/- 14, and 1035 +/- 724% above individual baselines, respectively. Similarly, peak concentrations of serum T(4), T(3), and Tg, after 0.9 mg rhTSH administration, were 102 +/- 16, 134 +/- 7, and 1890 +/- 768% above individual baselines, respectively. These data, compared with previously reported data for the responses to 0.1 mg rhTSH, indicated that 0.1, 0.3, and 0.9 mg rhTSH had similar quantitative stimulatory effects on thyroid hormone and Tg secretion, except that the T(4) response was greater in groups receiving 0.3 and 0.9 mg rhTSH than in the group receiving 0.1 mg rhTSH. We also studied the effect of rhTSH on the thyroid RAIU in the group that received 0.9 mg rhTSH. The 6- and 24-h RAIU values were significantly higher after rhTSH (pre-rhTSH, 6-h value = 12.5 +/- 1.8%; 24 h value = 23 +/- 2.7%; post-rhTSH, 6 h value = 27 +/- 4.8%; 24-h value = 41 +/- 4.2%). The stimulating effects of 0.9 mg rhTSH on the 6- and 24-h RAIUs were similar. rhTSH is a potent stimulator of T(4), T(3), and Tg secretion and the RAIU in normal subjects. Single doses greater than 0.1--0.3 mg do not seem to further enhance thyroid hormone or Tg secretion.

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BACKGROUND: Little has been studied about pregnant women's perceptions of their nurse's role during labor and delivery. The objective of this study was to determine nulliparous pregnant women's expectations of their nurse's role during labor and delivery as expressed during the last trimester of pregnancy. METHOD: Nulliparous women in childbirth classes were asked on a questionnaire, "What do you think your nurse's role will be during labor and delivery? You may list as many things as you wish." RESULTS: Fifty-seven completed surveys were collected. The women listed a total of 174 items. Approximately 29 percent of the nursing tasks listed by the nulliparous women were related to providing them with physical comfort and emotional support, 24 percent related to providing informational support, almost 21 percent were related to providing technical nursing care, and 21 percent related to monitoring of the baby, mother, or labor progress; approximately 5 percent related to indirect care (outside the room). CONCLUSION: The expectations of women in our study were in contrast with findings from two previous work sampling studies, in which nurses provided much less time giving women physical comfort, emotional support, and informational support than would have been expected by women in our study. Fulfilling women's expectations about childbirth can increase women's satisfaction with their birth experiences. Further studies can help maternity caregivers learn more about women's expectations.

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In the hip and sacroiliac joints, ankylosing spondylitis attacks the acetabulum over the femoral head and the ilium in preference to the sacrum. Both sites involve inflammation in bone subjacent to fibrocartilage with relative sparing of opposing, hyaline cartilage-surfaced mates. This disease appears to target connective tissues rich in fibrillin-1. A cell-mediated autoimmune response may be involved.

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UNLABELLED: Iterative reconstruction of SPECT images has recently become clinically available as an alternative to filtered backprojection (FBP). However, there is conflicting evidence on whether iterative reconstruction, such as with the ordered-subsets expectation maximization (OSEM) algorithm, improves diagnostic performance over FBP. The study objective was to determine if the detection and localization of small lesions in simulated thoracic gallium SPECT images are better with OSEM reconstruction than with FBP, both with and without attenuation correction (AC). METHODS: Images were simulated using an analytic projector acting on the mathematic cardiac torso computer phantom. Perfect scatter rejection was assumed. Lesion detection accuracy was assessed using localization receiver operating characteristic methodology. The images were read by 5 nuclear medicine physicians. For each reconstruction strategy and for each observer, data were collected in 2 viewing sessions of 100 images. Two-way ANOVA and, when indicated, the Scheffé multiple comparisons test were applied to check for significant differences. RESULTS: Little difference in the accuracy of detection or localization was seen between FBP with and without AC. OSEM with AC extended the contrast range for accurate lesion detection and localization over that of the other methods investigated. Without AC, no significant difference between OSEM and FBP reconstruction was detected. CONCLUSION: OSEM with AC may improve the detection and localization of thoracic gallium-labeled lesions over FBP reconstruction.

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A case of low thyroid radioactive iodine uptake (RAIU) thyrotoxicosis due to a large struma ovarii comprising pure thyroid tissue is presented, including a detailed diagnostic evaluation, histopathology, and demonstration of rapid recovery of native thyroid function after surgical excision. In addition, the first comprehensive analysis of thyroglobulin obtained from an ovarian struma is reported.

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OBJECTIVE: To evaluate whether extended use of continuous passive motion (CPM) may allay the pain of walking, diminish disease effect, and increase the usual walking speed in patients with osteoarthritis (OA) of the hip. METHODS: This pilot study comprised 21 patients with Kellgren-Lawrence grade 2-4 OA of the hip who used CPM for periods of 1.2 to 7.6 h daily throughout a 12 week trial. RESULTS: Significant improvements were found in the patients' assessment of pain on visual analog scale, Sickness Impact Profile, self-selected walking speed, and the number of subjects who decreased their medication usage. None of these improvements was related to the radiographic grade of the patients' OA or the daily duration of CPM. CONCLUSION: Although regular exercise is now routinely recommended to patients with OA, there has been relatively little study of specific exercise programs. As such investigations are undertaken, we believe CPM should be included among the options that are studied.

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Tumor detection can be significantly affected by filtering so determining an optimal filter is an important aspect of establishing a clinical reconstruction protocol. The purpose of this study was to identify the cut-off frequency of a Butterworth filter used in a filtered backprojection (FBP) reconstruction that maximized the detection and localization accuracy of 1 cm spherical lesions in Ga-67 citrate, thoracic SPECT images. Image quality was evaluated by means of a localization receiver operating characteristic (LROC) study using computer simulated images. Projection data were generated using the mathematical cardiac-torso digital phantom with a clinically realistic background source distribution. The images were reconstructed using FBP with multiplicative Chang attenuation correction and fifth-order Butterworth filtering. The cut-off frequencies considered were 0.25, 0.32, 0.47, and 0.79 cm(-1) for the case of three-dimensional (3D) post-filtering and 0.25, 0.32, and 0.47 cm(-1) for two-dimensional (2D) post-filtering. The images were read by three research scientists and one board certified nuclear medicine clinician. The area under the LROC curve and the localization accuracy for all test conditions were compared using Scheffé's multiple comparisons test. It was found that 3D post-filtering using filters with cut-off frequencies of 0.32 and 0.47 cm(-1) resulted in the highest lesion detectability and localization accuracy. These two test conditions did not differ significantly from each other but were significantly better (p<0.05) than all of the 2D, and the 3D 0.79 cm(-1) cut-off frequency cases.

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OBJECTIVE: To investigate the role of the posterior tibial tendon in the flat foot deformity of rheumatoid arthritis (RA). METHODS: Eleven patients with hyperpronated feet and 9 without hyperpronation underwent magnetic resonance imaging (MRI) of the feet and ankles. Radial oblique double echo images provided cross sectional views of the posterior tibial tendon as it coursed behind and under the medial malleolus and inserted beneath the midfoot. RESULTS: Complete tears (Type III) of the posterior tibial tendon were seen in one patient with hyperpronation and in one without hyperpronation. However, partial tears (Types I and II) of the posterior tibial tendon were common, and when Type I-III posterior tibial tendon tears were grouped together, they were seen in 68% of flat feet and in 43% of feet that were not flat. Abnormalities of the tarsal sinus, including cortical erosions and replacement of the normal fat signal with intermediate signal soft tissue, were seen in 74% of flat feet and in 5% of feet that were not flat. CONCLUSION: Posterior tibial tendon tears are common in RA flat feet, but are usually incomplete and are not solely responsible for the flat foot deformity.

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