The genetic architecture of the human cerebral cortex

INTRODUCTION The cerebral cortex underlies our complex cognitive capabilities. Variations in human cortical surface area and thickness are associated with neurological, psychological, and behavioral traits and can be measured in vivo by magnetic resonance imaging (MRI). Studies in model organisms have identified genes that influence cortical structure, but little is known about common genetic variants that affect human cortical structure. RATIONALE To identify genetic variants associated with human cortical structure at both global and regional levels, we conducted a genome-wide association meta-analysis of brain MRI data from 51,665 individuals across 60 cohorts. We analyzed the surface area and average thickness of the whole cortex and 34 cortical regions with known functional specializations. RESULTS We identified 306 nominally genome-wide significant loci (P < 5 × 10−8) associated with cortical structure in a discovery sample of 33,992 participants of European ancestry. Of the 299 loci for which replication data were available, 241 loci influencing surface area and 14 influencing thickness remained significant after replication, with 199 loci passing multiple testing correction (P < 8.3 × 10−10; 187 influencing surface area and 12 influencing thickness). Common genetic variants explained 34% (SE = 3%) of the variation in total surface area and 26% (SE = 2%) in average thickness; surface area and thickness showed a negative genetic correlation (rG = −0.32, SE = 0.05, P = 6.5 × 10−12), which suggests that genetic influences have opposing effects on surface area and thickness. Bioinformatic analyses showed that total surface area is influenced by genetic variants that alter gene regulatory activity in neural progenitor cells during fetal development. By contrast, average thickness is influenced by active regulatory elements in adult brain samples, which may reflect processes that occur after mid-fetal development, such as myelination, branching, or pruning. When considered together, these results support the radial unit hypothesis that different developmental mechanisms promote surface area expansion and increases in thickness. To identify specific genetic influences on individual cortical regions, we controlled for global measures (total surface area or average thickness) in the regional analyses. After multiple testing correction, we identified 175 loci that influence regional surface area and 10 that influence regional thickness. Loci that affect regional surface area cluster near genes involved in the Wnt signaling pathway, which is known to influence areal identity. We observed significant positive genetic correlations and evidence of bidirectional causation of total surface area with both general cognitive functioning and educational attainment. We found additional positive genetic correlations between total surface area and Parkinson’s disease but did not find evidence of causation. Negative genetic correlations were evident between total surface area and insomnia, attention deficit hyperactivity disorder, depressive symptoms, major depressive disorder, and neuroticism. CONCLUSION This large-scale collaborative work enhances our understanding of the genetic architecture of the human cerebral cortex and its regional patterning. The highly polygenic architecture of the cortex suggests that distinct genes are involved in the development of specific cortical areas. Moreover, we find evidence that brain structure is a key phenotype along the causal pathway that leads from genetic variation to differences in general cognitive function

The pharmacological and clinical aspects behind dose loading of biological disease modifying anti-rheumatic drugs (bDMARDs) in auto-immune rheumatic diseases (AIRDs): rationale and systematic narrative review of clinical evidence

Contains fulltext : 225359.pdf (publisher's version ) (Open Access)BACKGROUND: Dose loading of biological disease modifying anti-rheumatic drugs (bDMARDs) in auto-immune rheumatic diseases (AIRDs) is performed to achieve steady state drug concentrations earlier after treatment start compared to dosing regimens without loading. Although loading inherently results in increased costs, treatment targets in terms of reduced disease activity may be achieved at an earlier state. It is an interesting topic that, surprisingly, has not received much attention in literature. METHODS: In this review, we aimed at providing a theoretical description of the pharmacodynamic / -kinetic rationale for dose loading of bDMARDs in AIRDs and to systematically review the clinical evidence on the effectiveness of dose loading on disease activity in AIRDs. RESULTS: Only a small number of studies (n = 5) has been published comparing the effectiveness of dose loading versus a regimen without dose loading of bDMARDs in AIRDs, addressing abatacept (n = 2), certolizumab pegol (n = 1), and secukinumab (n = 2). These studies provide insufficient evidence on superiority of dose loading in terms of disease activity compared to a dosing regimen without loading, while safety issues might be comparable. CONCLUSIONS: Although dose loading is commonly adopted for several bDMARDs in AIRDs, scientific evidence on its effectiveness and safety is surprisingly scarce and does not suggest superiority compared to a regimen without dose loading. More research in this field, also with regard to the pharmaco-economic consequences of dose loading, is urgently needed

Intermediate-dose melphalan compared with myeloablative treatment in multiple myeloma: long-term follow-up of the Dutch Cooperative Group HOVON 24 trial.

Contains fulltext : 34603.pdf (publisher's version ) (Open Access)BACKGROUND AND OBJECTIVES. The Dutch-Belgian HOVON group performed a randomized phase 3 trial to compare single non-myeloablative intensive treatment with double, intensive treatment in previously untreated patients with multiple myeloma (MM). DESIGN AND METHODS. Three hundred and three patients with stage II/III MM were randomized after VAD induction chemotherapy to receive two cycles of non-myeloablative intermediate-dose melphalan (70 mg/m2) (single treatment) or the same regimen followed by cyclophosphamide 120 mg/kg iv plus total body irradiation (TBI) 9 Gy and autologous stem cell transplantation (double, intensive treatment). In both treatment arms interferon .IIa was given as maintenance until relapse/progression. RESULTS. A significantly higher proportion of patients achieved a complete remission (CR) on protocol treatment with double, intensive therapy (32 % vs 13 %, p<0.001). Double treatment produced better outcome in terms of event-free survival (median 22 vs 21 months, 28% vs 14% at 4 years and 15% vs 7% at 6 years after randomization; logrank p=0.013; univariate HR 0.74, 95% CI, 0.58-0.94), progression-free survival (median 27 vs 24 months, 33% vs 16% at 4 years, and 17% vs 9% at 6 years after randomization; logrank p=0.006; HR=0.71, 95% CI 0.56-0.91), but not overall survival (median 50 vs 55 months, 52% vs 56% at 4 years and 39% vs 36% at 6 years after randomization; logrank p=0.51; HR=1.10, 95% CI 0.83-1.46). The achievement of a CR had a favorable prognostic impact on event-free survival (HR=0.60 , 95% CI=0.44 -0.82 , p=0.001) and progression-free survival (HR=0.62 , 95% CI=0.45 -0.84, p=0.002). INTERPRETATION AND CONCLUSIONS. Double, intensive treatment resulted in a better CR rate, event-free survival and progression-free survival but not overall survival compared to single non-myeloablative treatment in previously untreated patients with multiple myeloma

Intensified 12-week CHOP (I-CHOP) plus G-CSF compared with standard 24-week CHOP (CHOP-21) for patients with intermediate-risk aggressive non-Hodgkin lymphoma: a phase 3 trial of the Dutch-Belgian Hemato-Oncology Cooperative Group (HOVON).

Contains fulltext : 53318.pdf (publisher's version ) (Closed access)Optimal dose and timing of CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) chemotherapy for aggressive non-Hodgkin lymphoma (NHL) is still an unresolved issue. We assessed whether dose intensifications with cyclophosphamide and doxorubicin might improve outcome in younger patients with intermediate-risk aggressive NHL. Previously untreated patients were assigned to receive either 8 courses of standard CHOP (n = 239) or 6 courses of intensified (I)-CHOP (n = 238). Although there was a tendency in favor of I-CHOP for overall survival (OS), disease-free survival (DFS), and event-free survival (EFS), the differences were not significant. However, although these analyses were not planned, when the intermediate-risk group was divided into low-intermediate- and high-intermediate-risk patients according to the International Prognostic Index (IPI), low-intermediate-risk patients had improved 6-year OS (67% vs 52%; P = .05), DFS (58% vs 45%; P = .06), and EFS (41% vs 30%; P = .21) when they were treated with I-CHOP compared with standard CHOP. On the other hand, high-intermediate-risk patients seem to have no benefit from I-CHOP. Although clinically relevant side effects occurred more often in the I-CHOP arm, treatment-related mortality was similar. These data suggest that I-CHOP might be preferable to standard CHOP in younger patients with low-intermediate-risk aggressive NHL

The value of fludarabine in addition to ARA-C and G-CSF in the treatment of patients with high-risk myelodysplastic syndromes and AML in elderly patients.

Item does not contain fulltextFludarabine in addition to cytosine-arabinoside (ARA-C) increases the accumulation of ARA-C-5'-triphosphate (ARA-CTP), which is responsible for the cytotoxic effect in leukemic blasts. In a randomized phase 3 trial, patients with high-risk myelodysplastic syndrome (MDS) (n = 91) or elderly patients with acute myeloid leukemia (AML) (n = 43) were randomized to receive 2 induction courses consisting of ARA-C (2 g/m2 days 1 through 5) and granulocyte colony-stimulating factor (G-CSF) (filgrastim, 5 microg/kg) during and after chemotherapy with or without fludarabine (25 mg/m2, days 1 through 5) (FLAG versus AG). Consolidation consisted of daunorubicin (45 mg/m2, days 1 through 3) and ARA-C (200 mg/m2, days 1 through 7). Complete remission (CR) rate following AG was 65% versus 71% with FLAG (P =.49). Overall survival (OS) at 24 months was 24% for AG treatment and 39% for FLAG (P =.32). Event-free survival (EFS) at 2 years was 10% and 19% (P =.31) for the AG and FLAG treatments, respectively. Platelet and granulocyte recovery times after the second cycle were prolonged in the FLAG treatment group. Grades 3 to 4 neurotoxicities were more often reported in the FLAG arm (14% versus 3%, P =.03), whereas no significant differences in other toxicities were observed. In a cohort of patients, the in vivo accumulation of ARA-CTP in leukemic cells was determined. Although ARA-CTP accumulation in leukemic cells after FLAG was enhanced, clinical outcome in terms of CR rate, OS, EFS, and disease-free survival (DFS) was not significantly improved by combining fludarabine with ARA-C

Chemotherapy only compared to chemotherapy followed by transplantation in high risk myelodysplastic syndrome and secondary acute myeloid leukemia; two parallel studies adjusted for various prognostic factors.

Comparisons of the effectiveness of chemotherapy and transplantation in AML in first complete remission (CR) have focused almost exclusively on patients with de novo disease. Here we used Cox modelling to compare these strategies in patients with MDS and s-AML treated by the Leukemia Group of the EORTC or at the MD Anderson Cancer Center. All patients were aged 15-60. The 184 EORTC patients received conventional dose ara-C + idarubicin + etoposide for remission induction, and after one consolidation course, were scheduled to receive an allograft, or an autograft if a sibling donor was unavailable. The 215 MDA patients received various high-dose ara-C containing induction regimens, and in CR, continued to receive these regimens at reduced dose for 6-12 months. CR rates were 54% EORTC and 63% MDA (P = 0.09). Sixty-five of the 100 EORTC patients who entered CR received a transplant in first CR. Disease-free survival in patients achieving CR was superior in the EORTC cohort, the 4-years DFS rates were 28.9% (s.e. = 4.8%) EORTC vs 17.3% (s.e. = 3.7%) MDA (P = 0.017). Survival from CR was not significantly different in the EORTC and MDA groups, as was survival from start of treatment. After accounting for prognostic factors the conclusions were unchanged. Despite various problems with the analysis discussed below, the data suggest that neither transplantation nor chemotherapy, as currently practised, can be unequivocally recommended for these patients in first CR and that questions as to the superior modality may be less important than the need to improve results with both

Achtergronden bij de richtlijn voor de behandeling van chronische myeloïde leukemie anno 2018 Deel 2: Het belang van responsmijlpalen, monitoring en mutaties en de behandeling van gevorderde CML-fasen

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