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The absence of aldehyde dehydrogenase 1 A1-positive cells in benign mammary stroma is associated with risk factors for breast cancer

In this study, aldehyde dehydrogenase 1 (ALDH1)-expressing cells in stroma of histologically normal breast tissue from premenopausal women were investigated in situ regarding cellular morphology, cell distribution, and relation to the additional stem cell markers, CD44 (+) and CD24 (-). These results were correlated with hormonal and genetic risk factors for breast cancer. Triple immunofluorescenc

Long-term risk of renal and urinary tract diseases in childhood cancer survivors : A population-based cohort study

Background Childhood cancer has been associated with long-term risk of urinary tract diseases, but risk patterns remain to be comprehensively investigated. We analysed the lifetime risk of urinary tract diseases in survivors of childhood cancer in the Nordic countries. Methods We identified 32,519 one-year survivors of childhood cancer diagnosed since the 1940s and 1950s in the five Nordic cancer

Body mass index and suicide methods

Overweight and obesity is associated with lower rates of suicide. However, little is known about the association with different suicide methods. We studied the association between groups of body mass index and suicide methods. We identified all medicolegal autopsy cases with a cause of death due to external causes in Sweden during 1999-2013 (N = 39,368) and included 11,715 suicides and 13,316 acci

A reduced population of CD103+CD11b+ dendritic cells has a limited impact on oral Salmonella infection

CD103+CD11b+ dendritic cells (DC) are the major migratory DC subset in the small intestine lamina propria (siLP) and their survival is dependent on the transcription factor interferon regulatory factor 4 (IRF4). Mice with a DC-specific deletion of irf4 (CD11c-cre.Irf4 mice) have reduced mucosal CD103+CD11b+ DC and altered T cell differentiation to protein antigen. The influence of CD103+CD11b+ DC

Pulmonary and pleural lymphatic endothelial cells from pediatric, but not adult, patients with Gorham-Stout disease and generalized lymphatic anomaly, show a high proliferation rate

Background: Gorham-Stout disease (OMIM 123880) and generalized lymphatic anomaly are two rare disorders of lymphendothelial growth in which thoracic involvement with chylothorax is a feared complication. Currently it is believed that both disorders are prenatal malformations that progress slowly after birth. Several pharmaceuticals with antiproliferative properties, including interferon-α-2b, rapa

Structural conditions for oscillations and multistationarity in aggregate monotone systems

We provide necessary and sufficient structural conditions for multistationarity and oscillations in aggregate monotone systems, defined as the interconnection of stable monotone components. Our classification is based on the presence of exclusively positive or exclusively negative cycles in the system aggregate graph, whose nodes are the monotone subsystems. The results presented here scale up the

Plant tuning: a robust Lyapunov approach

We consider the problem of tuning the output of a static plant whose model is unknown, under the only information that the input-output function is monotonic in each component or, more in general, that its Jacobian belongs to a known polytope of matrices. As a main result, we show that, if the polytope is robustly non-singular (or has full rank, in the non-square case), then a suitable tuning sche

Molecular Titration Promotes Oscillations and Bistability in Minimal Network Models with Monomeric Regulators

Molecular titration is emerging as an important biochemical interaction mechanism within synthetic devices built with nucleic acids and the CRISPR/Cas system. We show that molecular titration in the context of feedback circuits is a suitable mechanism to enhance the emergence of oscillations and bistable behaviors. We consider biomolecular modules that can be inhibited or activated by input monome

A switched system approach to dynamic race modelling

The paper presents and analyses some nonlinear continuous-time dynamic models of social systems whose members, groups or individuals, may change partners and/or opponents at any time, according to a greedy criterion. The main structural properties of these models, which belong to the class of positive switching systems, are investigated with particular regard to the existence of solutions, their p

Polyhedral Lyapunov functions for structural stability of biochemical systems in concentration and reaction coordinates

Structural properties, independent of specific parameter values, can explain the robustness of biochemical systems. In this paper we consider the framework previously proposed by the authors to assess structural stability of biochemical reaction networks with monotone reaction rates, which considers systems in concentration coordinates, and we show that the results can be applied to systems in rea

Neural stem cell transplantation for the treatment of primary torsion dystonia : A case report

Primary torsion dystonia (PTD) occurs due to a genetic mutation and often advances gradually. Currently, there is no therapy available that is able to inhibit progression. Neural stem cells (NSCs) are being investigated as potential therapies for neurodegenerative diseases, such as stroke and trauma. The present study evaluated the clinical effectiveness of NSC transplantation in an 18-year-old ma

Computing the structural influence matrix for biological systems

We consider the problem of identifying structural influences of external inputs on steady-state outputs in a biological network model. We speak of a structural influence if, upon a perturbation due to a constant input, the ensuing variation of the steady-state output value has the same sign as the input (positive influence), the opposite sign (negative influence), or is zero (perfect adaptation),

Compartmental flow control : Decentralization, robustness and optimality

We consider the flow control problem for a general class of compartmental nonlinear systems, which can be associated with a graph whose nodes represent subsystems with their own internal dynamics, and whose arcs represent flow links among them. We consider a network-decentralized control: each agent controls a link between two nodes and decides its actions based on the states of these nodes only.

Robust constrained Model Predictive Control of fast electromechanical systems

A major drawback hinders the application of Model Predictive Control (MPC) to the regulation of electromechanical systems or, more generally, systems with fast dynamics: the time needed for the online computation of the control is often too long with respect to the sampling time. This paper shows how this problem can be overcome by suitably implementing the MPC technique. The main idea is to compu

Network-decentralized control strategies for stabilization

We consider the problem of stabilizing a class of systems formed by a set of decoupled subsystems (nodes) interconnected through a set of controllers (arcs). Controllers are network-decentralized, i.e., they use information exclusively from the nodes they interconnect. This condition requires a block-structured feedback matrix, having the same structure as the transpose of the overall input matrix

Inverse kinematics by means of convex programming : Some developments

A novel approach to the problem of inverse kinematics for redundant manipulators has been recently introduced: by considering the joints as point masses in a fictitious gravity field, and by adding proper constraints to take into account the length of the links, the kinematic inversion may be cast as a convex programming problem. Such a problem can be solved in an efficient way and may be easily m

Set invariance for delay difference equations

This paper deals with set invariance for time delay systems. The first goal of the paper is to review the known necessary or sufficient conditions for the existence of invariant sets with respect to dynamical systems described by discrete-time delay difference equations (dDDEs). Secondly, we address the construction of invariant sets in the original state space (also called D-invariant sets) by ex

Properties of switching-dynamics race models

The paper analyses some continuous-time dynamic models that describe the evolution of social systems characterized by the possibility of changing the alliances among the parties involved or damaging one's competitors. At any time each participant, either an individual or a coalition, can decide to form or terminate a bond, or to start or stop damaging an opponent (i.e., to switch from a network co