132 resultados para fluorodeoxyglucose f 18


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Ectopic ACTH Cushing's syndrome (EAS) is often caused by neuroendocrine tumors (NETs) of lungs, pancreas, thymus, and other less frequent locations. Localizing the source of ACTH can be challenging. A 64-year-old man presented with rapidly progressing fatigue, muscular weakness, and dyspnea. He was in poor condition and showed facial redness, proximal amyotrophy, and bruises. Laboratory disclosed hypokalemia, metabolic alkalosis, and markedly elevated ACTH and cortisol levels. Pituitary was normal on magnetic resonance imaging (MRI), and bilateral inferior petrosal sinus blood sampling with corticotropin-releasing hormone stimulation showed no significant central-to-periphery gradient of ACTH. Head and neck, thoracic and abdominal computerized tomography (CT), MRI, somatostatin receptor scintigraphy (SSRS), and (18)F-deoxyglucose-positron emission tomography (FDG-PET) failed to identify the primary tumor. (18)F-dihydroxyphenylalanine (F-DOPA)-PET/CT unveiled a 20-mm nodule in the jejunum and a metastatic lymph node. Segmental jejunum resection showed two adjacent NETs, measuring 2.0 and 0.5 cm with a peritoneal metastasis. The largest tumor expressed ACTH in 30% of cells. Following surgery, after a transient adrenal insufficiency, ACTH and cortisol levels returned to normal values and remain normal over a follow-up of 26 months. Small mid-gut NETs are difficult to localize on CT or MRI, and require metabolic imaging. Owing to low mitotic activity, NETs are generally poor candidates for FDG-PET, whereas SSRS shows poor sensitivity in EAS due to intrinsically low tumor concentration of type-2 somatostatin receptors (SST2) or to receptor down regulation by excess cortisol. However, F-DOPA-PET, which is related to amine precursor uptake by NETs, has been reported to have high positive predictive value for occult EAS despite low sensitivity, and constitutes a useful alternative to more conventional methods of tumor localization. LEARNING POINTS: Uncontrolled high cortisol levels in EAS can be lethal if untreated.Surgical excision is the keystone of NETs treatment, thus tumor localization is crucial.Most cases of EAS are caused by NETs, which are located mainly in the lungs. However, small gut NETs are elusive to conventional imaging and require metabolic imaging for detection.FDG-PET, based on tumor high metabolic rate, may not detect NETs that have low mitotic activity. SSRS may also fail, due to absent or low concentration of SST2, which may be down regulated by excess cortisol.F-DOPA-PET, based on amine-precursor uptake, can be a useful method to localize the occult source of ACTH in EAS when other methods have failed.

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Peroxisome proliferator-activated receptors (PPARs) are ligand activated transcription factors belonging to the nuclear hormone receptor superfamily. PPARγ is involved in many different activities in the epidermis, such as keratinocyte differentiation, permeability barrier recovery, dermal wound closure, sebaceous gland formation, sebocyte differentiation, and melanogenesis. Preclinical studies with PPARγ ligands on various skin diseases have been performed and they could represent a new strategy in the treatment of scarring alopecia. PPARγ deserves further studies as therapeutic target, likely not with the current drugs, but with future new classes of safer molecules and in combined therapies.

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Positron emission tomography (PET) data are commonly analyzed in terms of regional intensity, while covariant information is not taken into account. Here, we searched for network correlates of healthy cognitive function in resting state PET data. PET with [(18)F]-fluorodeoxyglucose and a test of verbal working memory (WM) were administered to 35 young healthy adults. Metabolic connectivity was modeled at a group level using sparse inverse covariance estimation. Among 13 WM-relevant Brodmann areas (BAs), 6 appeared to be robustly connected. Connectivity within this network was significantly stronger in subjects with above-median WM performance. In respect to regional intensity, i.e., metabolism, no difference between groups was found. The results encourage examination of covariant patterns in FDG-PET data from non-neurodegenerative populations.

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The aim of this study was to examine the prevalence of trisomies 18 and 13 in Europe and the prevalence of associated anomalies. Twenty-five population-based registries in 16 European countries provided data from 2000-2011. Cases included live births, fetal deaths (20+ weeks' gestation), and terminations of pregnancy for fetal anomaly (TOPFAs). The prevalence of associated anomalies was reported in live births. The prevalence of trisomy 18 and trisomy 13 were 4.8 (95%CI: 4.7-5.0) and 1.9 (95%CI: 1.8-2.0) per 10,000 total births. Seventy three percent of cases with trisomy 18 or trisomy 13 resulted in a TOPFA. Amongst 468 live born babies with trisomy 18, 80% (76-83%) had a cardiac anomaly, 21% (17-25%) had a nervous system anomaly, 8% (6-11%) had esophageal atresia and 10% (8-13%) had an orofacial cleft. Amongst 240 Live born babies with trisomy 13, 57% (51-64%) had a cardiac anomaly, 39% (33-46%) had a nervous system anomaly, 30% (24-36%) had an eye anomaly, 44% (37-50%) had polydactyly and 45% (39-52%) had an orofacial cleft. For babies with trisomy 18 boys were less likely to have a cardiac anomaly compared with girls (OR = 0.48 (0.30-0.77) and with trisomy 13 were less likely to have a nervous system anomaly [OR = 0.46 (0.27-0.77)]. Babies with trisomy 18 or trisomy 13 do have a high proportion of associated anomalies with the distribution of anomalies being different in boys and girls. © 2015 Wiley Periodicals, Inc.

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BACKGROUND: To compare the prognostic value of different anatomical and functional metabolic parameters determined using [(18)F]FDG-PET/CT with other clinical and pathological prognostic parameters in cervical cancer (CC). METHODS: Thirty-eight patients treated with standard curative doses of chemo-radiotherapy (CRT) underwent pre- and post-therapy [(18)F]FDG-PET/CT. [(18)F]FDG-PET/CT parameters including mean tumor standardized uptake values (SUV), metabolic tumor volume (MTV) and tumor glycolytic volume (TGV) were measured before the start of CRT. The post-treatment tumor metabolic response was evaluated. These parameters were compared to other clinical prognostic factors. Survival curves were estimated by using the Kaplan-Meier method. Cox regression analysis was performed to determine the independent contribution of each prognostic factor. RESULTS: After 37 months of median follow-up (range, 12-106), overall survival (OS) was 71 % [95 % confidence interval (CI), 54-88], disease-free survival (DFS) 61 % [95 % CI, 44-78] and loco-regional control (LRC) 76 % [95 % CI, 62-90]. In univariate analyses the [(18)F]FDG-PET/CT parameters unfavorably influencing OS, DFS and LRC were pre-treatment TGV-cutoff ≥562 (37 vs. 76 %, p = 0.01; 33 vs. 70 %, p = 0.002; and 55 vs. 83 %, p = 0.005, respectively), mean pre-treatment tumor SUV cutoff ≥5 (57 vs. 86 %, p = 0.03; 36 vs. 88 %, p = 0.004; 65 vs. 88 %, p = 0.04, respectively) and a partial tumor metabolic response after treatment (9 vs. 29 %, p = 0.0008; 0 vs. 83 %, p < 0.0001; 22 vs. 96 %, p < 0.0001, respectively). After multivariate analyses a partial tumor metabolic response after treatment remained as an independent prognostic factor unfavorably influencing DFS and LRC (RR 1:7.7, p < 0.0001, and RR 1:22.6, p = 0.0003, respectively) while the pre-treatment TGV-cutoff ≥562 negatively influenced OS and DFS (RR 1:2, p = 0.03, and RR 1:2.75, p = 0.05). CONCLUSIONS: Parameters capturing the pre-treatment glycolytic volume and metabolic activity of [(18)F]FDG-positive disease provide important prognostic information in patients with CC treated with CRT. The post-therapy [(18)F]FDG-PET/CT uptake (partial tumor metabolic response) is predictive of disease outcome.

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Objective - To describe the global and language development of children with cleft palate or cleft lip and palate at the age of 18 months, and to evaluate whether the type of cleft has an impact on psychomotor development. Study Design - Prospective cohort study. Settings - Tertiary care hospital Patients - All children born between December 2002 and November 2009 with an orofacial cleft, operated and seen at the developmental unit (UD) of the same hospital at the age of 18 months. Outcome Measures - Developmental quotients of the Griffiths Mental Development Scale and the French Communicative Development Inventory (IFDC) were used to assess the overall and language development of the children. Statistics- The population characteristics were described with means for continuous variables, and frequencies for binary or categorical variables. Chi-squared and regression analysis were used to analyse the results. Results - 69 children with clefts were examined at the age of 18 months with the IFDC and the Griffith test. The results showed that there was no significant difference in the test results of language development and global psychomotor development between the children with different types of clefts, and all were within the normal range. Conclusion - Psychomotor development is not affected by orofacial clefts, and there is no difference between children with cleft palate or cleft lip and palate.