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991.
Sabine Pfeifenbring Imke Metz David Kremer Patrick Küry Hans‐Peter Hartung Wolfgang Brück 《Glia》2013,61(8):1250-1260
Impaired remyelination in multiple sclerosis (MS) might be due to the failure of oligodendrocyte precursor cells (OPC) to differentiate into myelinating oligodendrocytes. Animal experimental data have shown that p57kip2 inhibits oligodendroglial differentiation, indicating that this factor could contribute to remyelination failure. This study investigates oligodendroglial p57kip2 expression and its association with remyelination in MS lesions. To analyze the potential association of p57kip2 expression with human oligodendroglial maturation, double immunofluorescence staining was performed on brain tissue from 30 MS patients and 20 controls. Anti‐p57kip2 antibody was combined with either anti‐Nogo‐A to label mature oligodendrocytes or anti‐Olig2 antibodies to identify immature OPCs. We evaluated MS lesions with or without remyelination, the periplaque white matter (PPWM) as well as control white matter (WM). p57kip2‐expressing cells were assessed and correlated with the extent of remyelination. Most Nogo‐A‐positive oligodendrocytes (range, 87–98%) and all Olig2strong‐positive OPCs expressed p57kip2 in MS lesions, in the PPWM and in control WM. p57kip2 expression in oligodendrocytes and OPCs were similar in MS lesions with remyelination compared to MS lesions lacking remyelination. Interestingly, all oligodendroglial lineage cells showed nuclear p57kip2 expression only, with mature oligodendrocytes expressing p57kip2 at low or intermediate levels and OPCs featuring strong expression levels, indicating that this factor may be dynamically expressed during maturation processes. Therefore, p57kip2 appears to be widely expressed in the human oligodendroglial lineage, and potential beneficial effects on remyelination in the MS brain are not based on subcellular p57kip2 localization shifts, as suggested by previous animal experiments. GLIA 2013;61:1250–1260 相似文献
992.
Ina Giegling Beatrice Balzarro Stefano Porcelli Martin Schäfer Annette M. Hartmann Marion Friedl Bettina Konte Philipp Krämer Hans-Jürgen Möller Diana De Ronchi Hans H. Stassen Alessandro Serretti Dan Rujescu 《European archives of psychiatry and clinical neuroscience》2013,263(1):65-74
The present study explores whether ankyrin repeat and kinase domain containing 1 (ANKK1) and dopamine receptor D2 (DRD2) variants could predict efficacy and tolerability of haloperidol in the treatment of psychotic patients. We also attempted to replicate findings in a group of schizophrenic patients from the Clinical Antipsychotic Trials in Intervention Effectiveness (CATIE) study. Eighty-eight acutely psychotic patients were genotyped for 9 ANKK1 and 27 DRD2 SNPs. Treatment efficacy and tolerability were assessed using the Positive and Negative Symptoms Scale and the Udvalg for Kliniske Undersogelser side effects rating scales, respectively. Multivariate analyses were employed to test possible influences of single-nucleotide polymorphisms on clinical and safety variables. Analysis of haplotypes was also performed. Outcomes in the replication sample were response versus nonresponse and the presence versus absence of motor side effects at 1 month of treatment. rs2242592 within ANKK1 gene and rs1124493 within DRD2 gene were associated with clinical improvement (p = 0.008 and p = 0.001, respectively). Results were confirmed in the allelic analysis. Three haplotype blocks, one among ANKK1 and two among DRD2 gene were associated with better clinical improvement. Our results were not replicated in the CATIE sample, although rs11604671, which is in strong linkage disequilibrium with rs2242592, was associated with response in the replication sample. Our findings support a possible role of ANKK1 and DRD2 variability on haloperidol efficacy. However, due to the discrepancies between the results in the two samples, our results need further validation. 相似文献
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995.
Lenny Kamelia Laura de Haan Bert Spenkelink Ben Bruyneel Hans B. Ketelslegers Peter J. Boogaard Ivonne M.C.M. Rietjens 《Journal of applied toxicology : JAT》2020,40(3):330-341
In vitro assays presently used for prenatal developmental toxicity (PDT) testing only assess the embryotoxic potential of parent substances and not that of potentially embryotoxic metabolites. Here we combined a biotransformation system, using hamster liver microsomes, with the ES-D3 cell differentiation assay of the embryonic stem cell test (EST) to compare the in vitro PDT potency of two 5-ring polycyclic aromatic hydrocarbons (PAHs), benzo[a]pyrene (BaP) and dibenz[a,h]anthracene (DBA), and dimethyl sulfoxide extracts from five PAH-containing petroleum substances (PS) and a gas-to-liquid base oil (GTLb), with and without bioactivation. In the absence of bioactivation, DBA, but not BaP, inhibited the differentiation of ES-D3 cells into beating cardiomyocytes in a concentration-dependent manner. Upon bioactivation, BaP induced in vitro PDT, while its major metabolite 3-hydroxybenzo[a]pyrene was shown to be active in the EST as well. This means BaP needs biotransformation to exert its embryotoxic effects. GTLb extracts tested negative in the EST, with and without bioactivation. The PS-induced PDT in the EST was not substantially changed following bioactivation, implying that metabolism may not play a crucial role for the PS extracts under study to exert the in vitro PDT effects. Altogether, these results indicate that although some PAH require bioactivation to induce PDT, some do not and this latter appears to hold for the (majority of) the PS constituents responsible for the in vitro PDT of these complex substances. 相似文献
996.
Sangjune Laurence Lee Ananth Ravi Gerard Morton Andrew Loblaw Chia-Lin Tseng Masoom Haider Jure Murgic Alexandru Nicolae Mark Semple Hans T. Chung 《Brachytherapy》2019,18(5):567-573
PurposeTo explore the changes in T2-weighted (T2w) and apparent diffusion coefficient (ADC) magnetic resonance imaging -derived radiomic features of the gross tumor volume (GTV) from focal salvage high-dose-rate prostate brachytherapy (HDRB) and to correlate with clinical parameters.Materials and MethodsEligible patients included those with biopsy-confirmed local recurrence that correlated with MRI (T2w, ADC). Patients received 27 Gy in 2 fractions separated by 1 week to a quadrant consisting of the GTV. The MRI was repeated 1 year after HDRB. GTVs, planning target volumes, and normal prostate tissue control volumes were identified on the pre- and post-HDRB MRIs. Radiomic features from each GTV were extracted, and principle component analysis identified features with the highest variance.ResultsPre- and post-HDRB MRIs were obtained from 14 trial patients. Principle component analysis showed that 18 and 17 features contributed to 93% and 86% of the variance observed in the T2w and ADC data, respectively. Sixteen T2w features and 1 ADC GTV feature were different from the control volumes in the pre-HDRB images (p < 0.05). Ten T2w and 7 ADC GTV post-HDRB features were different from those of pre-HDRB (p < 0.05).ConclusionsExploratory analysis reveals several radiomic features in the T2w and ADC image GTVs that distinguish the GTV from healthy prostate tissue and change significantly after salvage HDRB. 相似文献
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998.
Care improves self-reported daily functioning of adolescents with emotional and behavioural problems
Verhage Vera Reijneveld Sijmen. A. Wunderink Charlotte Grietens Hans Almansa Josue Jansen Danielle E. M. C. 《European child & adolescent psychiatry》2022,31(11):1685-1693
European Child & Adolescent Psychiatry - Emotional and behavioural problems (EBP) have a negative impact on various life domains of adolescents. Receiving care for EBP may improve the... 相似文献
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