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So far, no suitable 5‐HT7R radioligand exists for clinical positron emission tomography (PET) imaging. [18F]2FP3 was first tested in vivo in cats, and the results were promising for further evaluations. Here, we evaluate the radioligand in pigs and non‐human primates (NHPs). Furthermore, we investigate species differences in 5‐HT7R binding with [3H]SB‐269970 autoradiography in post‐mortem pig, NHP, and human brain tissue. Specific binding of [18F]2FP3 was investigated by intravenous administration of the 5‐HT7R specific antagonist SB‐269970. [3H]SB‐269970 autoradiography was performed as previously described. [18F]2FP3 was synthesized in an overall yield of 35% to 45%. High brain uptake of the tracer was found in both pigs and NHPs; however, pretreatment with SB‐269970 only resulted in decreased binding of 20% in the thalamus, a 5‐HT7R–rich region. Autoradiography on post‐mortem pig, NHP, and human tissues revealed that specific binding of [3H]SB‐269970 was comparable in the thalamus of pig and NHP. Despite the high uptake of [18F]2FP3 in both species, the binding could only be blocked to a limited degree with the 5‐HT7R antagonists. We speculate that the affinity of the radioligand is too low for imaging the 5‐HT7Rs in vivo and that part of the PET signal arises from targets other than the 5‐HT7R.  相似文献   
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Purpose

To determine whether personality disorders (PDs) are associated with increased risk of disability pensioning in young adults, independent of other common mental disorders.

Methods

2,770 young adults from the general population were assessed for PDs by the Structured Interview for DSM-IV Personality, and for common mental disorders by the Composite of International Diagnostic Interview. These data were linked to the Norwegian National Insurance Administration’s recordings of disability benefits for a 10-year period. Logistic regression analyses were applied to investigate the association between PDs and disability pensioning. The analyses were conducted for three types of PD measures: categorical diagnoses (any PD), dimensional scores of individual PDs and higher order components retrieved by principal component analyses.

Results

Having any PD was strongly associated with disability pensioning, regardless of disability diagnosis. The estimated odds ratio (OR) was substantially higher for PDs [OR 4.69 (95 % confidence interval (CI) 2.6–8.5)] than for mood disorders [OR 1.3 (CI 0.7–2.3)] and anxiety disorders [OR 2.3 (CI 1.3–4.3)]. Measured dimensionally, all PD traits except antisocial traits were significantly associated with disability pensioning. After adjusting for co-occurring traits of other PDs, only schizoid, dependent and borderline PD traits showed a significant positive association with disability pension, while antisocial traits showed a significant negative association. The principal component analyses showed that negative affectivity, psychoticism, and detachment was associated with an increased risk of disability pensioning, while antagonism/disinhibition and obsessivity were not.

Conclusions

PDs are strongly associated with disability pensioning in young adults, and might be more important predictors of work disability than anxiety and depressive disorders. Certain aspects of pathologic personalities are particularly important predictors of disability.  相似文献   
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Background: Patients with inflammatory bowel disease (IBD) and symptoms of irritable bowel syndrome (IBS) may be intolerant to fermentable carbohydrates (FODMAPs). The aim of this study was to test the feasibility of eliminating and subsequently reintroducing FODMAPs in patients with IBS symptoms as part of the IBD manifestation and to compare the severity of IBS symptoms and pain, bloating and quality of life (QoL). Methods: An eight-week randomised open-label FODMAP elimination with double-blinded, crossover provocations of FODMAP and placebo. Diet patients were on a low-FODMAP diet for eight weeks with blinded two-week provocations after two and six weeks. Questionnaires, blood and stool samples were collected. Results: Patient enrolment was challenging. Nineteen participants were included in the study. Eliminating low FODMAP for two weeks resulted in significant decreases in pain and bloating scores (p < 0.003), whereas there were no statistical differences in pain scores between diet patients and controls. Pain and bloating scores increased, returning to baseline levels after two weeks of double-blinded provocations with placebo, (p > 0.05). Conclusions: The results document the possibility of performing a randomised controlled study following the gold standard for testing food intolerance with blinding of the Low FODMAP diet. Recruitment of participants was challenging.  相似文献   
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Blood-brain barrier permeability to the inhibitory neurotransmitter gamma-aminobutyric acid (GABA), to sucrose and to sodium was studied in rats with galactosamine-induced liver damage and hepatic encephalopathy by means of an arterial integral uptake technique. Permeability to GABA was unaltered in all examined brain regions (2.47 +/- 0.25.10(-5) cm3.s-1.g-1, mean +/- S.D.) as compared to control rats (2.49 +/- 0.19.10(-5) cm3.s-1.g-1). The permeability to sucrose (galactosamine 0.25 +/- 0.02 vs. controls 0.24 +/- 0.02.10(-5) cm3.s-1.g-1) and to sodium (galactosamine 5.33 +/- 0.04 vs. controls 5.40 +/- 0.05.10(-5) cm3.s-1.g-1) was also unchanged in hepatic encephalopathy. At the time of investigation mean liver function measured by antipyrine clearance was reduced from 0.39 in control rats to 0.23 ml/min/100 g body wt. in galactosamine-treated animals. The present study does not support the suggestion that peripheral GABA penetrates the blood-brain barrier to any higher extent in hepatic encephalopathy. This provides evidence against at least part of the GABA-hypothesis. Furthermore, an unspecific increased blood-brain barrier permeability in hepatic encephalopathy, as measured by sucrose and sodium uptake, was not found. It is concluded that the GABA-theory requires further careful reevaluation.  相似文献   
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BACKGROUND: Alternatively activated macrophages expressing the CD163 and CD206 surface receptors are the dominant immune-cell type found in the placenta. The placental number and distribution of macrophages is altered in pre-eclampsia, and the generalised inflammatory reaction associated with pre-eclampsia might lead to shedding of soluble CD163 into the circulation. METHODS: Serum samples from 18 women with pre-eclampsia and 90 normal pregnancies were obtained from a longitudinal study of 955 pregnant women at Randers County Hospital, Denmark. sCD163 and Neopterin were measured by ELISA on samples collected in weeks 18, 28, 32, and 38 of pregnancy. RESULTS: sCD163 levels in pregnancy (2-3 mg/l) were similar to previously measured levels in non-pregnant women, and did not increase from week 18 to 38. There was a tendency towards higher sCD163 in week 38 in pre-eclamptic women compared to healthy women. Neopterin increased throughout pregnancy in both healthy (from median 5.4 to 6.7 nmol/l, p<0.0001) and pre-eclamptic women (from 5.0 to 8.0 nmol/l, p<0.0001), but there were no differences between groups at any time-point. sCD163 correlated to neopterin in both the control (r=0.25, p<0.0001) and in the pre-eclampsia group (r=0.32, p=0.011). C-reactive protein was higher in pre-eclampsia than in healthy pregnancies by week 38 (159 versus 91 nmol/l, p=0.0189). CONCLUSIONS: The macrophage serum-markers sCD163 and neopterin are not pre-symptomatic nor prognostic markers for pre-eclampsia.  相似文献   
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