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Pregnancy-induced metabolic changes are regulated by signals from an expanded adipose organ. Placental growth factor (PlGF), acting through vascular endothelial growth factor receptor-1, may be among those signals. There is a steep rise in circulating PlGF during normal pregnancy, which is repressed in gravidas who develop preeclampsia. PlGF-deficiency in mice impairs adipose vascularization and development. Here we studied young-adult PlGF-deficient (PlGF(-/-)) and wild-type mice on a high-fat diet in the nongravid state and at embryonic day (E) 13.5 or E18.5 of gestation. Litter size and weight were normal, but E18.5 placentas were smaller in PlGF(-/-) pregnancies. PlGF(-/-) mice showed altered intraadipose dynamics, with the following: 1) less blood vessels and fewer brown, uncoupling protein (UCP)-1-positive, adipocytes in white sc and perigonadal fat compartments and 2) white adipocyte hypertrophy. The mRNA expression of beta(3)-adrenergic receptors, peroxisome proliferator-activated receptor-gamma coactivator-1alpha, and UCP-1 was decreased accordingly. Moreover, PlGF(-/-) mice showed hyperinsulinemia. Pregnancy-associated changes were largely comparable in PlGF(-/-) and wild-type dams. They included expanded sc fat compartments and adipocyte hypertrophy, whereas adipose expression of key angiogenesis/adipogenesis (vascular endothelial growth factor receptor-1, peroxisome proliferator-activated receptor-gamma(2)) and thermogenesis (beta(3)-adrenergic receptors, peroxisome proliferator-activated receptor-gamma coactivator-1alpha, and UCP-1) genes was down-regulated; circulating insulin levels gradually increased during pregnancy. In conclusion, reduced adipose vascularization in PlGF(-/-) mice impairs adaptive thermogenesis in favor of energy storage, thereby promoting insulin resistance and hyperinsulinemia. Pregnancy adds to these changes by PlGF-independent mechanisms. Disturbed intraadipose dynamics is a novel mechanism to explain metabolic changes in late pregnancy in general and preeclamptic pregnancy in particular.  相似文献   
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The low frequency of antigen‐specific naïve T cells has challenged numerous laboratories to develop various techniques to study the naïve T‐cell repertoire. Here, we combine the generation of naïve repertoire‐derived antigen‐specific T‐cell lines based on MHC‐tetramer staining and magnetic‐bead enrichment with in‐depth functional assessment of the isolated T cells. Cytomegalovirus (CMV) specific T‐cell lines were generated from seronegative individuals. Generated T‐cell lines consisted of a variety of immunodominant CMV‐epitope‐specific oligoclonal T‐cell populations restricted to various HLA‐molecules (HLA‐A1, A2, B7, B8, and B40), and the functional and structural avidity of the CMV‐specific T cells was studied. Although all CMV‐specific T cells were isolated based on their reactivity toward a specific peptide‐MHC complex, we observed a large variation in the functional avidity of the MHC‐tetramer positive T‐cell populations, which correlated with the structural avidity measured by the recently developed Streptamer koff‐rate assay. Our data demonstrate that MHC‐tetramer staining is not always predictive for specific T‐cell reactivity, and challenge the sole use of MHC‐tetramers as an indication of the peripheral T‐cell repertoire, independent of the analysis of functional activity or structural avidity parameters.  相似文献   
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European Child & Adolescent Psychiatry - Parents of children with ADHD experience several difficulties while raising their children and report lower levels of knowledge about their...  相似文献   
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Journal of Neurology - The relationship between visual impairment and cognitive performance in multiple sclerosis (MS) remains poorly understood. To determine associations between visual acuity and...  相似文献   
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neurogenetics - The second most common form of Charcot-Marie-Tooth neuropathy (CMT), X-linked CMT type X1 (CMTX1), is caused by coding and non-coding mutations in the gap junction beta 1 (GJB1)...  相似文献   
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ObjectiveWomen with early-stage, ER + breast cancer are recommend to receive genomic profiling tests, such as the 21-gene Recurrence Score (RS) test, to guide treatment decisions. We examined test- and treatment-related information discussed and the associations between RS categories and aspects of communication during patient-oncologist clinical encounters.MethodsAs part of a larger trial, clinical encounters (N = 46) were audiorecorded and coded for 1) RS- and treatment-related information, 2) shared decision making, 3) patient active participation, and 4) oncologist patient-centered communication. We examined differences by RS category using mixed models, adjusting for nesting within oncologist.ResultsPatients with a high RS were more likely to receive a chemotherapy recommendation (p < .01), hear about the risks/side effects of chemotherapy (p < .01), and offer their preferences (p = .02) than those with intermediate or low RS. Elements of shared decision making increased with RS. Oncologist patient-centered communication (M = 4.09/5, SD = .25) and patient active participation (M = 3.5/4, SD = 1.0) were high across RS.ConclusionFindings suggest that disease severity, rather than clinical uncertainty, impact treatment recommendations and shared decision making.Practice implicationsOncologists adjust test- and treatment-related information and shared decision making by disease severity. This information provides a framework to inform decision making in complex cancer and genomics settings.  相似文献   
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