64 research outputs found
Role of cardiac resynchronization therapy in the development of new-onset atrial fibrillation: A single-center prospective study.
Albeit several studies examined the association between cardiac resynchronization therapy (CRT) and atrial fibrillation (AF) in heart failure (HF), results are still unclear and quite conflicting. We thereby designed a single-center prospective study to determine whether CRT has a favorable effect on the incidence of new-onset AF in a homogeneous population of patients with non-ischemic idiopathic dilated cardiomyopathy and severe heart failure HF. We enrolled 58 patients, AF naïve when received CRT. After 1 year of follow-up our population was subdivided into responders (72.4%) and non (27.6%), so to compare the incidence of AF after 1, 2 and 3 years of follow-up in these two groups. Already after 1 year, there is a significant (p<0.05) difference in new-onset AF in non-responder patients respect to responders (18.2% vs 3.3%). These data are confirmed at 2 year (33.3% vs 12.2%) and 3 year (50.0% vs 15.0%) follow-up. In particular, at 3 year follow-up, non-responders have an increased risk to develop new-onset AF (OR=5.67, 95% confidence interval = 1.36-23.59, p=0.019). The present work suggests a possible favorable role of this non-pharmacological therapy, on the prevention of AF
Introduction: the literature of the Anthropocene
Diletta De Cristofaro and Daniel Cordle introduce the special issue on the Literature of the Anthropocene. They provide the context for the issue and flesh out the main concerns of the essays included: form, scale, the reckoning of the human with the non-human, time, and the relationship between the Humanities and the Sciences
The influence of neighborhood characteristics on police officers\u27 encounters with persons suspected to have a serious mental illness
Objective: Police officers\u27 decisions and behaviors are impacted by the neighborhood context in which police encounters occur. For example, officers may use greater force and be more likely to make arrests in disadvantaged neighborhoods. We examined whether neighborhood characteristics influence police encounters with individuals suspected to have a serious mental illness, addictive disorder, or developmental disability. Method: We obtained data on 916 encounters from 166 officers in six jurisdictions in Georgia, USA and abstracted geographical data pertaining to the location of these encounters from United States Decennial Census data. Encounters were nested within 163 census tracts. Officer-reported data covered general encounter characteristics, the officer\u27s perception of the subject\u27s condition, subject demographics, use of force, and disposition of the encounter (e.g., arrest v. referral or transport to treatment services). Geographical data included 17 variables representing population and housing characteristics of the census tracts, from which three indices pertaining to neighborhood income, stability, and immigration status were derived using factor-analytic techniques. We then examined associations of these indices with various encounter-related variables using multi-level analysis. Results: Encounters taking place in higher-income and higher-stability census tracts were more likely to be dispatch-initiated and take place in a private home compared to those in lower-income and lower-stability neighborhoods. In higher-income neighborhoods, encounters were more likely to involve a subject suspected to have a mental illness (as opposed to an addictive disorder or developmental disability) and less likely to involve a subject suspected to have alcohol problems. The officer\u27s level of force used was not associated with neighborhood factors. Regarding disposition, although the likelihood of arrest was unrelated to neighborhood characteristics, encounters taking place in higher-immigrant neighborhoods were more likely to result in referral or transport to services than those in lower-immigrant neighborhoods. Conclusion: Neighborhood characteristics are important to consider in research on police interactions with individuals with serious mental illnesses, addictive disorders, or developmental disabilities. Such research could inform departmental training policies and procedures based on the needs of the jurisdictions served. (C) 2014 Elsevier Ltd. All rights reserved
Teaching the Basics of Reactive Oxygen Species and their Relevance to Cancer Biology: Mitochondrial Reactive Oxygen Species Detection, Redox Signaling, and Targeted Therapies
Reactive oxygen species (ROS) have been implicated in tumorigenesis (tumor initiation, tumor progression, and metastasis). Of the many cellular sources of ROS generation, the mitochondria and the NADPH oxidase family of enzymes are possibly the most prevalent intracellular sources. In this article, we discuss the methodologies to detect mitochondria-derived superoxide and hydrogen peroxide using conventional probes as well as newly developed assays and probes, and the necessity of characterizing the diagnostic marker products with HPLC and LC-MS in order to rigorously identify the oxidizing species. The redox signaling roles of mitochondrial ROS, mitochondrial thiolperoxidases, and transcription factors in response to mitochondria-targeted drugs are highlighted. ROS generation and ROS detoxification in drug-resistant cancer cells and the relationship to metabolic reprogramming are discussed. Understanding the subtle role of ROS in redox signaling and in tumor proliferation, progression, and metastasis as well as the molecular and cellular mechanisms (e.g., autophagy) could help in the development of combination therapies. The paradoxical aspects of antioxidants in cancer treatment are highlighted in relation to the ROS mechanisms in normal and cancer cells. Finally, the potential uses of newly synthesized exomarker probes for in vivo superoxide and hydrogen peroxide detection and the low-temperature electron paramagnetic resonance technique for monitoring oxidant production in tumor tissues are discussed
Movements detection of deep seated gravitational slope deformations by means of InSAR data and photogeological interpretation: northern Sicily case study
We investigated the northern-central portion of Sicily region (southern Italy) using aerial photographs and Synthetic Aperture Radar (SAR) data obtained by ERS1 and ERS2 satellites. This area shows a geological-structural setting generated by the tectonic superposition of Apenninic-Maghrebian carbonatic structures on terrigenous deposits. Such a structural setting favoured the development of large-scale gravity driven phenomena (known in the geological literature as deep-seated gravitational slope deformations) that are mostly responsible for the landscape evolution of the whole area. Morphological evidences such as landslides, sacking or rock-flow, lateral spread and block slide can be detected from photogeological analysis. In order to understand the temporal behaviour and spatial distribution of such deformations we applied the interferometric SAR (InSAR) technique. Interferograms show fringe patterns spatially coinciding with some of the large-scale gravitative phenomena previously identified by means of aerialphoto analysis. The comparison between photogeological data and InSAR results allows delimiting the active sectors in the study area
Thrombin A-Chain: Activation Remnant or Allosteric Effector?
Although prothrombin is one of the most widely studied enzymes in biology, the role of the thrombin A-chain has been neglected in comparison to the other domains. This paper summarizes the current data on the prothrombin catalytic domain A-chain region and the subsequent thrombin A-chain. Attention is given to biochemical characterization of naturally occurring prothrombin A-chain mutations and alanine scanning mutants in this region. While originally considered to be simply an activation remnant with little physiologic function, the thrombin A-chain is now thought to play a role as an allosteric effector in enzymatic reactions and may also be a structural scaffold to stabilize the protease domain
The relationship between seismic deformation and deep seated gravitational
This paper re-evaluates the origin of some peculiar patterns of ground deformation observed by
space geodetic techniques during the two earthquakes of September 26th of the Colfiorito seismic
sequence. The surface displacement field due to the fault dislocation, as modeled with the classic
Okada elastic formulations, shows some areas with high residuals which cannot be attributed to
unsimulated model complexities. The latter was investigated using geomorphological analysis, by
recognising the geologic evidence of deep seated gravitational slope deformations (DSGSD) of the
block-slide type. The shape and direction of the co-seismic ground displacement observed in these
areas are correlated with the expected pattern of movement produced by the reactivation of the
identified DSGSD. At least a few centimetres of negative Line of Sight ground displacement was
determined for the Costa Picchio, Mt. Pennino, and Mt. Prefoglio areas. A considerable horizontal
component of movement in the Costa Picchio DSGSD is evident from a qualitative analysis of
ascending and descending interferograms. The timing of the geodetic data indicates that the ground
movement occurred during the seismic shaking, and that it did not progress appreciably during the
following months. In this work it has been verified the seismic triggering of DSGSD previously
hypothesized by many authors. A further implication is that in the assessment of DSGSD hazard it is
necessary to consider the seismic input as an important cause of acceleration of the deformation rates
Geomorphological evolution of western Sicily, Italy
This paper proposes a morphoevolutionary model for western Sicily. Sicily is a chain–foredeep–foreland system still being built, with tectonic activity involving uplift which tends to create new relief. To reconstruct the morphoevolutionary model, geological, and geomorphological studies were done on the basis of field survey and aerial photographic interpretation. The collected data show large areas characterized by specific geological, geomorphological, and topographical settings with rocks, landforms, and landscapes progressively older from south to north Sicily. The achieved results display: (1) gradual emersion of new areas due to uplift, its interaction with the Quaternary glacio-eustatic oscillations of the sea level, and the following production of a flight of stair-steps of uplifted marine terraces in southern Sicily, which migrates progressively upward and inwards; in response to the uplift (2) triggering of down-cutting processes that gradually dismantle the oldest terraces; (3) competition between uplift and down-cutting processes, which is responsible for the genesis of river valleys and isolated rounded hills in central Sicily; (4) continuous deepening over time that results in the exhumation of older and more resistant rocks in northern Sicily, where the higher heights of Sicily are realized and the older forms are retained; (5) extensional tectonic event in the northern end of Sicily, that produces the collapse of large blocks drowned in the Tyrrhenian Sea and sealed by coastal-marine deposits during the Calabrian stage; (6) trigger of uplift again in the previously subsiding blocks and its interaction with coastal processes and sea level fluctuations, which produce successions of marine terraces during the Middle–Upper Pleistocene stages
Start-up in microgravity and local thermodynamic states of a hybrid loop thermosyphon/pulsating heat pipe
A wickless passive two phase closed loop heat transfer device especially designed for a future implementation on the heat transfer host module of the International Space Station is tested in relevant environment on board a parabolic flight. The tube internal diameter (3 mm) is larger than the static capillary threshold evaluated in normal gravity for this working fluid (FC-72), leading the device to work as a loop thermosyphon on ground and in hyper-gravity conditions, and as a Pulsating Heat Pipe when micro-gravity occurs. Novel start up tests, where the heat load has been provided after the occurrence of microgravity, show that the 20 s microgravity period is enough for the device activation and, most important, that the device activation is purely thermally induced and not affected by the previous acceleration field. Two miniaturized pressure transducers and direct fluid temperature measurement via two micro-thermocouples, allow to provide a detailed insight on the fluid local thermodynamics states both in the evaporator and in the condenser zone during microgravity. It is shown that the two-phase fluid close to the evaporator and the condenser is subjected to several degrees (up to 5 K) of superheating or subcooling. The level of subcooling seems to increase with the heat input level both in terms of temperature difference and in terms of percentage time with respect to the whole microgravity period
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