Radiological progression may originate from progressive disease (PD) or pseudoprogression/treatment-associated changes. We assessed radiological progression in O6-methylguanine-DNA methyltransferase ...(MGMT) promoter-methylated glioblastoma treated with standard-of-care chemoradiotherapy with or without the integrin inhibitor cilengitide according to the modified response assessment in neuro-oncology (RANO) criteria of 2017.
Patients with ≥ 3 follow-up MRIs were included. Preliminary PD was defined as a ≥ 25% increase of the sum of products of perpendicular diameters (SPD) of a new or increasing lesion compared to baseline. PD required a second ≥25% increase of the SPD. Treatment-associated changes require stable or regressing disease after preliminary PD.
Of the 424 evaluable patients, 221 patients (52%) were randomized into the cilengitide and 203 patients (48%) into the control arm. After chemoradiation with or without cilengitide, preliminary PD occurred in 274 patients (65%) during available follow-up, and 88 of these patients (32%) had treatment-associated changes, whereas 67 patients (25%) had PD. The remaining 119 patients (43%) had no further follow-up after preliminary PD. Treatment-associated changes were more common in the cilengitide arm than in the standard-of-care arm (24% vs. 17%; relative risk, 1.3; 95% CI, 1.004-1.795; P = .047). Treatment-associated changes occurred mainly during the first 6 months after RT (54% after 3 months vs. 13% after 6 months).
With the modified RANO criteria, the rate of treatment-associated changes was low compared to previous studies in MGMT promoter-methylated glioblastoma. This rate was higher after cilengitide compared to standard-of-care treatment. Confirmatory scans, as recommended in the modified RANO criteria, were not always available reflecting current clinical practice.
The present study is an analysis of a Czech political corruption network known as the Rath affair reconstructed with publicly available data. We argue that for the study of criminal networks it is ...fruitful to follow a multiplex approach, i.e., to distinguish several interdependent network dimensions and study how they are interrelated. Relational elements in corruption are identified, and we propose three dimensions that are essential for understanding the Rath network: pre-existing ties (e.g., marriage or co-membership of the same party), resource transfer (e.g., bribing), and collaboration (e.g., communication). The aim of the study was threefold. We aimed to examine if the network exhibits the core/periphery structure, to investigate the multiplex structure of the network by assessing the overlap of the main dimensions of the network, and to determine the central and multiplex actors while considering the differentiation of centrality according to the three network dimensions. The core/periphery model appears to have a perfect fit to the aggregated network, leading to a four-block adjacency matrix. Studying the frequency of ties in these blocks shows that collaboration ties are present in all the blocks, while resource transfer ties are mainly located between the core and periphery, and pre-existing ties are rare generally. We also identify central actors, none of which are strategically positioned, occupying more visible positions instead. The majority of actors display strong multiplexity in the composition of their own ties. In the conclusion the potential usefulness of multiplex descriptive measures and of mixed methods approaches, implications of our results for trust incriminal networks, and potential merits of analytical sociology approach are discussed.
The aim of this study was to unravel the interrelatedness of friendship and help, and to examine the characteristics of friendship and help networks. The effects of mutual versus one‐sided help ...relations on friendship initiation and maintenance, and vice versa, were examined. Friendship and help networks were analyzed (N = 953 students; 41 classrooms; Mage = 12.7). The results illustrate that friendship and help networks show some similarities, but only partly overlap and have distinct characteristics. Longitudinal multiplex social network analyses showed that mutual help was important for the maintenance of friendship, but not for the initiation of friendship. Further, particularly mutual friendships provided a context in which help took place. Implications of these findings are discussed.
Longitudinal studies of criminal networks are rare yet necessary to assess the adaptation and recovery of criminal networks after disruptions. We study the structural and individual effects of law ...enforcement disruption on criminal networks using longitudinal data on two Dutch jihadi networks (n1 = 57; n2 = 26). We expect that actors in criminal networks under disruption seek security and to remain concealed as much as possible. We argue how the structural properties of networks as well as mechanisms operating at the actor level might change after a disruption. We used descriptive measures of network cohesion together with core-periphery model fit and modularity to analyse the structural changes in the networks. To obtain the actor-level tendencies, we used undirected stochastic actor oriented models. At the structural level, both networks display opposite tendencies – the larger one is becoming less cohesive after the disruption, whereas the smaller network counter-intuitively becomes structurally more cohesive. Despite the structural differences, the actor-level mechanisms are similar in both studied networks with actors being inclined towards triadic closure and reliance on pre-existing ties. Our study demonstrates the importance of considering the analytical levels of networks and actors by showing that a disruption may disrupt the network at the structural level, while triggering contradictory unintended consequences by increasing individual-level connectivity as in the case of our second network.
•Network structure and actor-level mechanisms in criminal networks changes after a disruption.•We analyse longitudinal data about two disrupted Dutch jihadi networks.•While the structure of network 1 was dismantled after the disruption, the cohesion of network 2 increased.•Te found triadic closure operating in both networks accompanied by pre-existing ties translation in network 1.
Although biopsies and tumor resection are prognostically beneficial for glioblastomas (GBM), potential negative effects have also been suggested. Here, using retrospective study of patients and ...intravital imaging of mice, we identify some of these negative aspects, including stimulation of proliferation and migration of non-resected tumor cells, and provide a strategy to prevent these adverse effects. By repeated high-resolution intravital microscopy, we show that biopsy-like injury in GBM induces migration and proliferation of tumor cells through chemokine (C-C motif) ligand 2 (CCL-2)-dependent recruitment of macrophages. Blocking macrophage recruitment or administrating dexamethasone, a commonly used glucocorticoid to prevent brain edema in GBM patients, suppressed the observed inflammatory response and subsequent tumor growth upon biopsy both in mice and in multifocal GBM patients. Taken together, our study suggests that inhibiting CCL-2-dependent recruitment of macrophages may further increase the clinical benefits from surgical and biopsy procedures.
Postoperative ischemia can lead to neurological deficits and is a known complication of glioma resection. There is inconsistency in documented incidence of ischemia after glioma resection, and the ...precise cause of ischemia is often unknown.
To assess the incidence of postoperative ischemia and neurological deficits after glioma resection and to evaluate their association with potential risk factors.
One hundred thirty-nine patients with 144 surgeries between January 2012 and September 2014 for World Health Organization (WHO) 2016 grade II-IV diffuse supratentorial gliomas with postoperative MRI within 72 hours were retrospectively included. Patient, tumor, and perioperative data were extracted from the electronic patient records. Occurrence of postoperative confluent ischemia, defined as new confluent areas of diffusion restriction, and new or worsened neurological deficits were analyzed univariably and multivariably using logistic regression models.
Postoperative confluent ischemia was found in 64.6% of the cases. Occurrence of confluent ischemia was associated with an insular location ( P = .042) and intraoperative administration of vasopressors ( P = .024) in multivariable analysis. Glioma location in the temporal lobe was related to an absence of confluent ischemia ( P = .01). Any new or worsened neurological deficits occurred in 30.6% and 20.9% at discharge from the hospital and at first follow-up, respectively. Occurrence of ischemia was significantly associated with the presence of novel neurological deficits at discharge ( P = .013) and after 3 months ( P = .024).
Postoperative ischemia and neurological deficit were significantly correlated. Intraoperative administration of vasopressors, insular glioma involvement, and absence of temporal lobe involvement were significantly associated with postoperative ischemia.
Using data on 32 actors and ties among them drawn from available court files, we combine analytical sociology with statistical models for networks in order to analyse a case of a counterfeit alcohol ...distribution network from the Czech Republic. We formulate a theory of action and identify relational mechanisms which could explain how the structure of the network emerged and describe. We use the exponential random graph model to test these mechanisms. The analysis reveals that the two actors capable of manufacturing the poisonous mixture were considerably though not optimally proximate to others enabling fast distribution of the mixture. Our model results that the structure was formed by mechanisms of triadic closure, negative tendency to concentrate ties, and tie translation of pre-existing ties into operational ties. We conclude with the discussion of the implications our approach for the study of criminal networks.
This study examined how classroom peer relations can be described in terms of the network of help relations among students, and the positions students take up in this help network, and whether the ...structure of adolescent classroom help networks and individual network positions were associated with academic achievement. Help networks were based on the peer nomination question "Who helps you with problems?" Building on previous studies on classroom climate and individual network position, higher academic achievement was expected in classrooms with: a dense help network; no or a few network isolates (referring to students that did not give or receive help at all); less segmentation in help relations; equally distributed help nominations. In addition, higher achievement was expected for individuals with more helpers and a more central position in the help network. Using the Dutch SNARE data (54 classrooms; 1,144 students), the multilevel models suggested that lower achievement was related to an unequal distribution of help relations in a classroom. Moreover, the centrality of individuals in the help network was linked to higher achievement. Classrooms varied strongly on network dimensions, and networks that would theoretically be expected to be most beneficial for achievement (with high density, a few isolates, low segmentation, and high equality) turned out to be highly uncommon. The findings demonstrated that subtle network processes were relevant for academic success, and that classroom network characteristics are associated with classroom-level variation in academic achievement. Descriptive results underlined the complexity of the social context of classrooms, and the absence of 'beneficial' classrooms suggests that researchers should adjust their notion of what is a beneficial or detrimental classroom environment for adolescents.
Depressive symptoms are common in glioma patients, and can negatively affect health-related quality of life (HRQOL). We performed a nation-wide randomized controlled trial to evaluate the effects of ...an online guided self-help intervention for depressive symptoms in adult glioma patients. Glioma patients with depressive symptoms were randomized to a 5-week online course based on problem-solving therapy, or a waiting list control group. After having received the intervention, the glioma patient groups combined were compared with patients with cancer outside the central nervous system (non-CNS cancer controls), who also received the intervention. Sample size calculations yielded 63 participants to be recruited per arm. The primary outcome depressive symptoms (CES-D) and secondary outcomes fatigue (Checklist Individual Strength (CIS)) and HRQOL (Short Form-36), were assessed online at baseline, post-intervention, and 3 and 12 months follow-up. In total, 89 glioma patients (intervention
N
= 45; waiting list
N
= 44) and 26 non-CNS cancer controls were included, of whom 35 and 54% completed the intervention, respectively. Recruitment could not be extended beyond 3.5 years due to funding. On depression, no statistically significant differences between the groups were found. Fatigue decreased post-treatment in the glioma intervention group compared with the waiting list group (
p
= 0.054,
d
= 0.306). At 12 months, the physical component summary (HRQOL) remained stable in glioma patients, while scores improved in non-CNS cancer controls (
p
= 0.035,
d
= 0.883). In this underpowered study, no evidence for the effectiveness of online guided self-help for depression or HRQOL in glioma patients was found, but it may improve fatigue.
Trial registration
Netherlands Trial Register NTR3223.
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