115 research outputs found
Identification of social relation within pedestrian dyads
This study focuses on social pedestrian groups in public spaces and makes an effort to identify the type of social relation between the group members. As a first step for this identification problem, we focus on dyads (i.e. 2 people groups). Moreover, as a mutually exclusive categorization of social relations, we consider the domain-based approach of Bugental, which precisely corresponds to social relations of colleagues, couples, friends and families, and identify each dyad with one of those relations. For this purpose, we use anonymized trajectory data and derive a set of observables thereof, namely, inter-personal distance, group velocity, velocity difference and height difference. Subsequently, we use the probability density functions (pdf) of these observables as a tool to understand the nature of the relation between pedestrians. To that end, we propose different ways of using the pdfs. Namely, we introduce a probabilistic Bayesian approach and contrast it to a functional metric one and evaluate the performance of both methods with appropriate assessment measures. This study stands out as the first attempt to automatically recognize social relation between pedestrian groups. Additionally, in doing that it uses completely anonymous data and proves that social relation is still possible to recognize with a good accuracy without invading privacy. In particular, our findings indicate that significant recognition rates can be attained for certain categories and with certain methods. Specifically, we show that a very good recognition rate is achieved in distinguishing colleagues from leisure-oriented dyads (families, couples and friends), whereas the distinction between the leisure-oriented dyads results to be inherently harder, but still possible at reasonable rates, in particular if families are restricted to parent-child groups. In general, we establish that the Bayesian method outperforms the functional metric one due, probably, to the difficulty of the latter to learn observable pdfs from individual trajectories
Social aspects of collision avoidance: A detailed analysis of two-person groups and individual pedestrians
Pedestrian groups are commonly found in crowds but research on their social
aspects is comparatively lacking. To fill that void in literature, we study the
dynamics of collision avoidance between pedestrian groups (in particular dyads)
and individual pedestrians in an ecological environment, focusing in particular
on (i) how such avoidance depends on the group's social relation (e.g.
colleagues, couples, friends or families) and (ii) its intensity of social
interaction (indicated by conversation, gaze exchange, gestures etc). By
analyzing relative collision avoidance in the ``center of mass'' frame, we were
able to quantify how much groups and individuals avoid each other with respect
to the aforementioned properties of the group. A mathematical representation
using a potential energy function is proposed to model avoidance and it is
shown to provide a fair approximation to the empirical observations. We also
studied the probability that the individuals disrupt the group by ``passing
through it'' (termed as intrusion). We analyzed the dependence of the
parameters of the avoidance model and of the probability of intrusion on
groups' social relation and intensity of interaction. We confirmed that the
stronger social bonding or interaction intensity is, the more prominent
collision avoidance turns out. We also confirmed that the probability of
intrusion is a decreasing function of interaction intensity and strength of
social bonding. Our results suggest that such variability should be accounted
for in models and crowd management in general. Namely, public spaces with
strongly bonded groups (e.g. a family-oriented amusement park) may require a
different approach compared to public spaces with loosely bonded groups (e.g. a
business-oriented trade fair).Comment: 25 pages, 15 figures, 3 table
Estimating social relation from trajectories
This study focuses on social pedestrian groups in public spaces and makes an effort to identify the social relation between the group members. We particularly consider dyads having coalitional or mating relation. We derive several observables from individual and group trajectories, which are suggested to be distinctive for these two sorts of relations and propose a recognition algorithm taking these observables as features and yielding an estimation of social relation in a probabilistic manner at every sampling step. On the average, we detect coalitional relation with 87% and mating relation with 81% accuracy. To the best of our knowledge, this is the first study to infer social relation from joint (loco)motion patterns and we consider the detection rates to be a satisfactory considering the inherent challenge of the problem
Maternal Epigenetic Dysregulation as a Possible Risk Factor for Neurodevelopmental Disorders
Neurodevelopmental Disorders (NDs) are a heterogeneous group of disorders and are considered multifactorial diseases with both genetic and environmental components. Epigenetic dysregulation driven by adverse environmental factors has recently been documented in neurodevelopmental disorders as the possible etiological agent for their onset. However, most studies have focused on the epigenomes of the probands rather than on a possible epigenetic dysregulation arising in their mothers and influencing neurodevelopment during pregnancy. The aim of this research was to analyze the methylation profile of four well-known genes involved in neurodevelopment (BDNF, RELN, MTHFR and HTR1A) in the mothers of forty-five age-matched AS (Asperger Syndrome), ADHD (Attention Deficit Hyperactivity Disorder) and typically developing children. We found a significant increase of methylation at the promoter of the RELN and HTR1A genes in AS mothers compared to ADHD and healthy control mothers. For the MTHFR gene, promoter methylation was significantly higher in AS mothers compared to healthy control mothers only. The observed dysregulation in AS mothers could potentially contribute to the affected condition in their children deserving further investigation
MEK blockade converts AML differentiating response to retinoids into extensive apoptosis
: The aberrant function of transcription factors and/or kinase-based signaling pathways that regulate the ability of hematopoietic cells to proliferate, differentiate, and escape apoptosis accounts for the leukemic transformation of myeloid progenitors. Here, we demonstrate that simultaneous retinoid receptor ligation and blockade of the MEK/ERK signaling module, using the small-molecule inhibitor CI-1040, result in a strikingly synergistic induction of apoptosis in both acute myeloid leukemia (AML) and acute promyelocytic leukemia (APL) cells with constitutive ERK activation. This proapoptotic synergism requires functional RAR and RXR retinoid receptors, as demonstrated using RAR- and RXR-selective ligands and RAR-defective cells. In the presence of MEK inhibitors, however, retinoid-induced chromatin remodeling, target-gene transcription, and granulocytic differentiation are strikingly inhibited and apoptosis induction becomes independent of death-inducing ligand/receptor pairs; this suggests that apoptosis induction by combined retinoids and MEK inhibitors is entirely distinct from the classical "postmaturation" apoptosis induced by retinoids alone. Finally, we identify disruption of Bcl-2-dependent mitochondrial homeostasis as a possible point of convergence for the proapoptotic synergism observed with retinoids and MEK inhibitors. Taken together, these results indicate that combined retinoid treatment and MEK blockade exert powerful antileukemic effects and could be developed into a novel therapeutic strategy for both AML and APL
Zoledronic acid induces a significant decrease of circulating endothelial cells and circulating endothelial precursor cells in the early prostate cancer neoadjuvant setting
Purpose: Published data demonstrated that zoledronic acid (ZOL) exhibits antiangiogenetic effects. A promising tool for monitoring antiangiogenic therapies is the measurement of circulating endothelial cells (CECs) and circulating endothelial precursor cells (CEPs) in the peripheral blood of patients. Our aim was to investigate the effects of ZOL on levels of CECs and CEPs in localized prostate cancer. Methods: Ten consecutive patients with a histologic diagnosis of low-risk prostate adenocarcinoma were enrolled and received an intravenous infusion of ZOL at baseline (T0), 28 days (T28) and 56 days (T56). Blood samples were collected at the following times: T0 (before the first infusion of ZOL), T3 (72 h after the first dose), T28, T56 (both just before the ZOL infusion) and T84 (28 days after the last infusion of ZOL) and CEC/CEP levels were directly quantified by flow cytometry at all these time points. Results: Our analyses highlighted a significant reduction of mean percentage of CECs and CEPs after initiation of ZOL treatment [p = 0.014 (at day 3) and p = 0.012 (at day 84), respectively]. Conclusion: These preliminary results demonstrate that ZOL could exert an antiangiogenic effect in early prostate cancer through CEP and CEC modulation
Aberrant Proliferative and Apoptotic Pathways in Acute Lymphoblastic Leukemia (ALL): Molecular Therapies to Overcome Chemo-Resistance
ERK1/2 phosphorylation is an independent predictor of complete remission in newly diagnosed adult acute lymphoblastic leukemia
Abstract
Extracellular signal-regulated kinase-1/2 (ERK1/2) is frequently found constitutively activated (p-ERK1/2) in hematopoietic diseases, suggesting a role in leukemogenesis. The aim of this study was to assess the expression and clinical role of p-ERK1/2 in adult acute lymphoblastic leukemia (ALL). In 131 primary samples from adult de novo ALL patients enrolled in the Gruppo Italiano per le Malattie Ematologiche dell'Adulto (GIMEMA) Leucemia Acute Linfoide (LAL) 2000 protocol and evaluated by flow cytometry, constitutive ERK1/2 activation was found in 34.5% of cases; these results were significantly associated with higher white blood cell (WBC) values (P = .013). In a multivariate analysis, p-ERK1/2 expression was an independent predictor of complete remission achievement (P = .027). Effective approaches toward MEK inhibition need to be explored in order to evaluate whether this may represent a new therapeutic strategy for adult ALL patients
High Erk-1 activation and Gadd45a expression as prognostic markers in high risk pediatric haemolymphoproliferative diseases
Studies on activated cell-signaling pathways responsible for neoplastic transformation are numerous in solid tumors and in adult leukemias. Despite of positive results in the evolution of pediatric hematopoietic neoplasias, there are some high-risk subtypes at worse prognosis. The aim of this study was to asses the expression and activation status of crucial proteins involved in cell-signaling pathways in order to identify molecular alterations responsible for the proliferation and/or escape from apoptosis of leukemic blasts. The quantitative and qualitative expression and activation of Erk-1, c-Jun, Caspase8, and Gadd45a was analyzed, by immunocytochemical (ICC) and western blotting methods, in bone marrow blasts of 72 patients affected by acute myeloid leukemia (AML), T-cell acute lymphoblastic leukemia (ALL) and stage IV non-Hodgkin Lymphoma (NHL). We found an upregulation of Erk-1, Caspase8, c-Jun, and Gadd45a proteins with a constitutive activation in 95.8%, 91.7%, 86.2%, 83.4% of analyzed specimens, respectively. It is worth noting that all AML patients showed an upregulation of all proteins studied and the high expression of GADD45a was associated to the lowest DFS median (p = 0.04). On univariate analysis, only Erk-1 phosphorylation status was found to be correlated with a significantly shorter 5-years DFS in all disease subgroups (p = 0.033) and the lowest DFS median in ALL/NHL subgroup (p = 0.04). Moreover, the simultaneous activation of multiple kinases, as we found for c-Jun and Erk-1 (r = 0.26; p = 0.025), might synergistically enhance survival and proliferation potential of leukemic cells. These results demonstrate an involvement of these proteins in survival of blast cells and, consequently, on relapse percentages of the different subgroups of patients
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