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One oxygen breath shortened the time to return of spontaneous circulation in severely asphyxiated piglets
Aim: Asphyxiated neonates should be resuscitated with air, but it remains unclear if oxygen supplementation is needed in ineffectively ventilated newborn infants. We studied the return of spontaneous circulation (ROSC) with oxygen or air in an experimental model of inadequate ventilation. Methods: Asphyxia was induced in 16 newborn piglets until their heart rate was
Absence of microRNA-21 does not reduce muscular dystrophy in mouse models of LAMA2-CMD
MicroRNAs (miRNAs) are short non-coding RNAs that modulate gene expression post-transcriptionally. Current evidence suggests that miR-21 plays a significant role in the progression of fibrosis in muscle diseases. Laminin-deficient congenital muscular dystrophy (LAMA2-CMD) is a severe form of congenital muscular dystrophy caused by mutations in the gene encoding laminin α2 chain. Mouse models dy3K/
Microstructure alterations in the hypothalamus in cranially radiated childhood leukaemia survivors but not in craniopharyngioma patients unaffected by hypothalamic damage
Objective: Metabolic complications are frequent in childhood leukaemia (ALL) survivors treated with cranial radiotherapy (CRT). These complications are potentially mediated by damage to the hypothalamus (HT), as childhood onset (CO) craniopharyngioma (CP) survivors without HT involvement are spared overt obesity. Diffusion tensor imaging (DTI) shows brain tissue microstructure alterations, by frac
Vaginal and urine self-sampling compared to cervical sampling for HPV-testing with the cobas 4800 HPV test
Background/Aim: To compare human papillomavirus (HPV) DNA detection in self-collected vaginal and urine samples with clinician-taken cervical samples in relation to histology. Materials and Methods: Self-collected vaginal, urine and clinician-taken cervical samples were analyzed from 218 women with the Cobas 4800 HPV test (Roche Molecular Diagnostics). Results: The sensitivity for detection of HPV
Qualitative and quantitative responses to press perturbations in ecological networks
Predicting the sign of press perturbation responses in ecological networks is challenging, due to the poor knowledge of the strength of the direct interactions among the species, and to the entangled coexistence of direct and indirect effects. We show in this paper that, for a class of networks that includes mutualistic and monotone networks, the sign of press perturbation responses can be qualita
Lifestyle in progression from hypertensive disorders of pregnancy to chronic hypertension in Nurses' Health Study II : Observational cohort study
Objectives To study the association between lifestyle risk factors and chronic hypertension by history of hypertensive disorders of pregnancy (HDP: gestational hypertension and pre-eclampsia) and investigate the extent to which these risk factors modify the association between HDP and chronic hypertension. Design Prospective cohort study. Setting Nurses' Health Study II (1991-2013). Participants 5
Aggregates of Monotonic Step Response systems : a structural classification
Complex dynamical networks can often be analysed as the interconnection of subsystems, to simplify the model and better understand the global behaviour. Some biological networks can be analysed as aggregates of monotone subsystems. Yet, monotonicity is a strong requirement and relies on the knowledge of an explicit state model. Systems with a Monotonic Step Response (MSR), which include input-outp
Polyhedral Lyapunov functions structurally ensure global asymptotic stability of dynamical networks iff the Jacobian is non-singular
For a vast class of dynamical networks, including chemical reaction networks (CRNs) with monotonic reaction rates, the existence of a polyhedral Lyapunov function (PLF) implies structural (i.e., parameter-free) local stability. Global structural stability is ensured under the additional assumption that each of the variables (chemical species concentrations in CRNs) is subject to a spontaneous infi
A bounded complementary sensitivity function ensures topology-independent stability of homogeneous dynamical networks
This paper investigates the topology-independent stability of homogeneous dynamical networks, composed of interconnected equal systems. Precisely, dynamical systems with identical nominal transfer function F(s) are associated with the nodes of a directed graph whose arcs account for their dynamic interactions, described by a common nominal transfer function G(s). It is shown that topology-independ
Nu är det dessvärre universitetens tur
Synen på kunskap är svenska skolans största problem
Interaction sign patterns in biological networks: from qualitative to quantitative criteria
In stable biological and ecological networks, the steady-state influence matrix gathers the signs of steady-state responses to step-like perturbations affecting the variables. Such signs are difficult to predict a priori, because they result from a combination of direct effects (deducible from the Jacobian of the network dynamics) and indirect effects. For stable monotone or cooperative networks,
Model-free tuning of plants with parasitic dynamics
We have recently considered the problem of tuning a static plant described by a differentiable input-output function, which is completely unknown, but whose Jacobian takes values in a known polytope of matrices: to drive the output to a given desired value, we have suggested an integral feedback scheme, whose convergence is ensured if the polytope of matrices is robustly full row rank. The suggest
Klart är att torsdagens attentat får konsekvenser, men situationen är komplex
Aggregates of Positive Impulse Response systems: a decomposition approach for complex networks
To simplify the analysis of complex dynamical networks, we have recently proposed an approach that decomposes the overall system into the sign-definite interconnection of subsystems with a Positive Impulse Response (PIR). PIR systems include and significantly generalise input-output monotone systems, and the PIR property (or equivalently, for linear systems, the Monotonic Step Response property) c
Atrial fibrosis : An obligatory component of arrhythmia mechanisms in atrial fibrillation?
Atrial fibrosis is common in atrial fibrillation (AF). Experimental studies have provided convincing evidence that fibrotic transformation of atrial myocardium results in deterioration of atrial conduction, increasing anisotropy of impulse propagation and building of boundaries that promote re-entry in the atrial walls that maybe directly relevant for the mechanisms responsible for maintaining AF.
Routine intraoperative cholangiography during cholecystectomy is a cost-effective approach when analysing the cost of iatrogenic bile duct injuries
Background: The total cost of bile duct injuries (BDIs) in an unselected national cohort of patients undergoing cholecystectomy are unknown. The aim was to evaluate costs associated with treatment of cholecystectomy-related BDIs and to calculate cost effectiveness of routine vs. on-demand intraoperative cholangiography (IOC). Methods: Data from Swedish patients suffering a BDI during a 5 year peri
Who are we – and who is I? : About Person and SELF
Optical Coherence Tomography Characterization of Coronary Lithoplasty for Treatment of Calcified Lesions : First Description
Objectives This study sought to determine the mechanistic effects of a novel balloon-based lithoplasty system on heavily calcified coronary lesions and subsequent stent placement using optical coherence tomography (OCT). Background The Shockwave Coronary Rx Lithoplasty System (Shockwave Medical, Fremont, California) delivers localized, lithotripsy-enhanced disruption of calcium within the target l