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991.
992.
Jelusić M Lukić IK Tambić-Bukovac L Dubravcić K Malcić I Rudan I Batinić D 《Clinical rheumatology》2007,26(8):1332-1334
The objective of this report is to explore the balance between serum and synovial fluid levels of interleukin (IL)-18 in children
with juvenile idiopathic arthritis (JIA). Blood samples were obtained from 81 children with JIA and 18 control children. Synovial
fluid samples were collected from 16 children with oligoarticular JIA. Concentrations of IL-18 were determined using commercial
kit. Patients with systemic JIA had higher serum levels of IL-18 than patients with other forms of JIA or control children,
both during the active (median, range: 6,240, 1,600–78,750 pg/ml) and inactive (1,615, 513–3,270 pg/ml) phase of disease [analysis
of variance (ANOVA), P < 0.05). Levels of IL-18 in sera of children with oligoarticular JIA (255, 89–4,342 pg/ml) were similar to the respective
synovial fluid levels (217, 89–1,245 pg/ml). Serum levels of IL-18 were proportional to the erythrocyte sedimentation rate
and levels of C-reactive protein, but inversely proportional to the haemoglobin levels. IL-18 appears to be an important mediator
of systemic JIA, while it seems of a lesser relevance in pathogenesis of other JIA forms. Therefore, inhibition of IL-18 might
be a base for a successful biological therapy for systemic JIA. 相似文献
993.
Vernaleken I Buchholz HG Kumakura Y Siessmeier T Stoeter P Bartenstein P Cumming P Gründer G 《Human brain mapping》2007,28(10):931-939
Dopamine neurotransmission influences those cognitive processes, which are generally regarded as prefrontal cortical functions. In previous positron-emission-tomography (PET) studies, net blood-brain clearance of [18F]-fluoro-l-DOPA (FDOPA) correlated with impaired cognitive performance in patients with Parkinson's disease or schizophrenia. We hypothesized that FDOPA influx also correlates with performance of cognitive tasks associated with prefrontal functioning in healthy volunteers. The net blood-brain clearance of FDOPA (K(in)(app)) was mapped in a group of 11 healthy volunteers and calculated in striatal volumes-of-interest. The Wisconsin-Card-Sorting-Test (WCST), Stroop-Test, Trail-Making-Test (TMT-A/B), and Continuous-Performance-Test (CPT-M) had been administered previously to the same subjects. No correlation of K(in) (app) with perseverative errors in WCST or age could be found. However, there were significant positive correlations between the magnitude of K(in)(app) in caudate nucleus, putamen, and midbrain with performance of the TMT-B, CPT-M, and the Stroop test. Highest correlations were found between the time needed to perform the Stroop interference task and the K(in)(app) of striatal areas (Caudate nucleus: -0.780, P = 0.005; putamen: -0.870, P < 0. 001). Thus, the present findings reveal a strong correlation between dopamine synthesis capacity in striatum of healthy volunteers and performance of cognitive tasks linked to the prefrontal cortex. 相似文献
994.
von Falck C Maecker B Schirg E Boerner AR Knapp WH Klein C Galanski M 《European journal of radiology》2007,63(3):427-435
Post transplant lymphoproliferative disease (PTLD) is a severe complication after solid organ or bone marrow transplantation. In pediatric transplant recipients PTLD is the most common malignancy. The aim of this study was to evaluate a possible role for positron emission tomography with [18F]-2-fluoro-2-desoxy-glucose (FDG) in the initial staging and in therapy monitoring of pediatric patients suffering from biopsy-proven CD20-positive PTLD after solid organ transplantation. Seven pediatric patients were included. All available imaging studies - CT (n=15), MRI (n=16) and PET/PETCT (n=16) - were reviewed on a lesion by lesion base. The performance of FDG-PET in the initial staging and during therapy with a chimeric anti-CD20 antibody was compared to conventional cross sectional imaging and correlated with the clinical outcome. FDG-PET identified all sites of disease as shown by CT/MRI and helped to clarify the significance of equivocal findings. The initial stage of disease was correctly identified by FDG-PET alone when compared to CT/MRI. During therapy, FDG-PET was superior to conventional cross-sectional imaging in the early evaluation of response. 相似文献
995.
GOALS: 18F FDG PET/CT is used for diagnosis, staging and establishing the response to therapy in various malignancies, including breast cancer (BC). Dedicated breast MRI (BMRI) is gaining a role in the management of BC patients (pts), demonstrating high sensitivity and specificity for detection of small lesions. We were therefore prompted to review our experience with PET and BMRI in BC. METHODS: This is a retrospective study of 21 women with BC, 30-76 years old, who had BMRI and whole-body FDG PET/CT at our institution from Jun 2002 to May 2005. A total of 6 patients (group A) had BMRI and PET/CT in the preoperative period and 15 patients (group B) had BMRI and PET/CT after surgery. Reinterpretation of the imaging studies for accuracy and data analysis from medical records were performed. RESULTS: For group A, BMRI identified breast lesions in 4 patients, while PET/CT was able to identify breast lesions in 5 patients. All these were proven to be malignancy on pathology examination. In group B, BMRI detected recurrent breast lesions in 8 patients, with 88.9% sensitivity and 83.3% specificity. In the same patient population, PET/CT was 33.3% sensitive and 91.7% specific. As a whole body examination, PET/CT revealed metastatic disease in 6 patients (100% sensitive and 90% specific). Overall, sensitivities and specificities for breast disease detection were 85.7% and 85.7% for BMRI, and 75% and 92.3% for 18F FDG PET/ CT. CONCLUSIONS: As expected, BMRI is more sensitive than PET/CT in the detection of breast lesions. However, PET/CT as a whole-body examination changed the management of disease by detection of distant lesions in 6 of the 21 patients. Our study suggests that 18F FDG PET/CT and BMRI should be considered as complimentary imaging tools in the pre- and postoperative work-up of patients diagnosed with breast cancer. 相似文献
996.
Kitajima K Nakamoto Y Senda M Onishi Y Okizuka H Sugimura K 《Annals of nuclear medicine》2007,21(7):405-410
Objective The aim of this study was to assess the physiological uptake of 18F-fluoro-2-deoxyglucose (FDG) by an apparently normal testis with combined positron emission tomography–computed tomography
(PET/CT) and its correlation with age, blood glucose level, and testicular volume.
Methods The testicular uptake of 18F-FDG, expressed as the standardized uptake value (SUV), was measured on PET/CT images in 203 men. The correlation between
SUV and age, blood glucose level, and testicular volume was assessed.
Results The SUV in the total of 406 testes was 2.44 ± 0.45 (range 1.23–3.85). The SUV was 2.81 ± 0.43 (2.28–3.85) for 30–39 years
(n = 12), 2.63 ± 0.45 (1.77–3.75) for 40–49 years (n = 64), 2.46 ± 0.35 (1.44–3.15) for 50–59 years (n = 82), 2.51 ± 0.41 (1.50–3.46) for 60–69 years (n = 86), 2.43 ± 0.47 (1.42–3.29) for 70–79 years (n = 86), and 2.18 ± 0.45 (1.23–3.03) for 80–89 years (n = 76). When we calculated the mean SUV of bilateral testes in each patient, there were significant statistical differences
between those in the age group of 30–39 years and 80–89 years, 40–49 years and 80–89 years, and 50–60 years and 80–89 years,
when using an unpaired test with Bonferroni correction. The laterality index (|L − R|/(L + R) × 2) in 203 men was 0.066 ±
0.067 (0–0.522). There was a mild correlation between the mean SUV and age (r = −0.284, P < 0.001) as well as between the mean SUV and mean volume (r = +0.368, P < 0.001). There was no correlation between the mean SUV and glucose blood level (r = −0.065, P = 0.358).
Conclusions Some uptake of FDG is observed in the normal testis and declines slightly with age. Physiological FDG uptake in the testis
should not be confused with pathological accumulation. 相似文献
997.
Objective This study was performed to evaluate the effects of intravenous (i.v.) contrast agent on semi-quantitative values and lymph
node (LN) staging of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) in patients with lung cancer.
Methods Thirty-five patients with lung cancer were prospectively included. Whole-body PET and nonenhanced CT images were acquired
60 min following the i.v. injection of 370 MBq 18F-FDG and subsequently, enhanced-CT images were acquired with the i.v. administration of 400 mg iodinated contrast agent without
positional change. PET images were reconstructed with both nonenhanced and enhanced CTs, and the maximum and average standardized
uptake values (SUVmax and SUVave) calculated from lung masses, LNs, metastatic lesions, and normal structures were compared. To evaluate the effects of the
i.v. contrast agent on LN staging, we compared the LN status on the basis of SUVs (cut-offs; SUVmax = 3.5, SUVave = 3.0).
Results The mean differences of SUVmax in normal structures between enhanced and nonenhanced PET/CT were 15.23% ± 13.19% for contralateral lung, 8.53% ± 6.11% for
aorta, 5.85% ± 4.99% for liver, 5.47% ± 6.81% for muscle, and 2.81% ± 3.05% for bone marrow, and those of SUVave were 10.17% ± 9.00%, 10.51% ± 7.89%, 4.95% ± 3.89%, 5.66% ± 9.12%, and 2.49% ± 2.50%, respectively. The mean differences
of SUVmax between enhanced and nonenhanced PET/CT were 5.89% ± 3.92% for lung lesions (n = 41), 6.27% ± 3.79% for LNs (n = 76), and 3.55% ± 3.38% for metastatic lesions (n = 35), and those of SUVave were 3.22% ± 3.01%, 2.86% ± 1.71%, and 2.33% ± 3.95%, respectively. Although one LN status changed from benign to malignant
because of contrast-related artifact, there was no up- or down-staging in any of the patients after contrast enhancement.
Conclusions An i.v. contrast agent may be used in PET/CT without producing any clinically significant artifact. 相似文献
998.
Mucoepidermoid carcinomas in the bronchial tree are extremely rare tumors. Such tumors are classified into low-grade and high-grade on the basis of histological criteria. Fluorine-18-fluorodeoxyglucose positron emission tomography (F-18 FDG PET) is a useful technique for the evaluation of pulmonary lesions; however, to our knowledge, F-18 FDG PET findings in mucoepidermoid carcinoma of the bronchus have been described in only a few cases. Identifiable focal F-18 FDG uptake has been reported in high-grade mucoepidermoid carcinoma, but it is unclear whether F-18 FDG accumulates in low-grade mucoepidermoid carcinoma. Here, we present the case of a 37-year-old woman, with pathologically proven low-grade mucoepidermoid carcinoma, who underwent high-resolution computed tomography (CT) and F-18 FDG PET/CT before treatment. 相似文献
999.
Kennedy JA Israel O Frenkel A Bar-Shalom R Azhari H 《European journal of nuclear medicine and molecular imaging》2007,34(4):517-531
Purpose To improve the PET image quality of a hybrid PET/CT scanner by merging CT borders with PET texture. PET/CT scanners provide
both high-resolution CT images showing anatomical details and PET images of low-resolution physiological information about
radiopharmaceutical uptake. Standard smoothing of noisy PET images may further impair PET resolution, reducing small lesion
detectability.
Methods The CT edge data and the PET texture data were merged using a modified form of an algorithm called HCT (hybrid computed tomography).
In merged PET/CT images, each PET pixel value was estimated by iteratively applying a corrected 2D Taylor expansion to each
of its eight neighbors. The spatial derivative term was used only near anatomical edges provided by the CT. This counts-preserving
algorithm was tested on a special resolution phantom and patient data sets obtained by PET/CT acquisitions.
Results The HCT algorithm provided phantom PET images with sharp borders and improved resolution (≤3 mm as compared to ≥4 mm). HCT
increased the signal to background contrast ratios by an average of 61% (40–89%) while maintaining noise reduction similar
to the Gaussian filtering standard in PET. In the clinical PET images, HCT allowed for an improved delineation of pulmonary
and pelvic lesions and an improved visualization of the brain.
Conclusion A new reconstruction algorithm for merging CT anatomical edge data with functional PET data has been introduced. The algorithm
smoothes noisy PET images while retaining sharper edges at corresponding anatomical borders, resulting in an improvement in
resolution and contrast ratio. 相似文献
1000.
Madar I Ravert H Nelkin B Abro M Pomper M Dannals R Frost JJ 《European journal of nuclear medicine and molecular imaging》2007,34(12):2057-2065
Purpose Mitochondrial dysfunction has been attributed a critical role in the etiology and pathogenesis of numerous diseases, and is
manifested by alterations of the organelle’s membrane potential (Δψm). This suggests that Δψm measurement can be highly useful for diagnostic purposes. In the current study, we characterized the capability of the novel
PET agent 18F-fluorobenzyl triphenylphosphonium (18F-FBnTP) to assess Δψm, compared with the well-established voltage sensor 3H-tetraphenylphosphonium (3H-TPP).
Methods
18F-FBnTP and 3H-TPP uptake under conditions known to alter Δψm and plasma membrane potential (Δψp) was assayed in the H345 lung carcinoma cell line. 18F-FBnTP biodistribution was assessed in CD1 mice using dynamic PET and ex vivo gamma well counting.
Results
18F-FBnTP and 3H-TPP demonstrated similar uptake kinetics and plateau concentrations in H345 cells. Stepwise membrane depolarization resulted
in a linear decrease in 18F-FBnTP cellular uptake, with a slope (−0.58±0.06) and correlation coefficient (0.94±0.07) similar (p>0.17) to those measured for 3H-TPP (−0.63±0.06 and 0.96±0.05, respectively). Selective collapse of Δψm caused a substantial decrease in cellular uptake for 18F-FBnTP (81.6±8.1%) and 3H-TPP (85.4±6.7%), compared with control. Exposure to the proapoptotic staurosporine, known to collapse Δψm, resulted in a decrease of 68.7±10.1% and 71.5±8.4% in 18F-FBnTP and 3H-TPP cellular uptake, respectively. 18F-FBnTP accumulated mainly in kidney, heart and liver.
Conclusion
18F-FBnTP is a mitochondria-targeting PET radiopharmaceutical responsive to alterations in membrane potential with voltage-dependent
performance similar to that of 3H-TPP. 18F-FBnTP is a promising new voltage sensor for detection of physiological and pathological processes associated with mitochondrial
dysfunction, such as apoptosis, using PET. 相似文献