Patient and Procedural Correlates of Fluoroscopy Use During Catheter Ablation in the Pediatric and Congenital Electrophysiology Lab

ObjectiveTo identify factors associated with fluoroscopy use in pediatric and congenital heart disease (CHD) patients.DesignRetrospective cohort.SettingPediatric electrophysiology lab in a single tertiary‐care children's hospital.PatientsThree hundred eighty‐three patients who underwent electrophysiology study and ablation between January 2010 and December 2012.MethodsAblation procedures in which nonfluoroscopic navigation was employed were reviewed. Procedures using ≥10 minutes of fluoroscopy (high‐fluoroscopy time; HF) were compared with those using <10 minutes (low‐fluoroscopy time; LF). Group comparison of characteristics was made in the entire cohort and in CHD and anatomically normal heart subsets.ResultsDuring the study period, 416 ablation procedures were performed involving 471 substrates in 383 patients. Median fluoroscopy time was 6.7 minutes overall and 5.1 minutes with anatomically normal hearts. LF comprised 61% of all ablation and 69% of anatomically normal hearts. LF procedures were associated with anatomically normal hearts (93% vs. 63%; P < .0001). In anatomically normal hearts, HF was associated with accessory pathways (64% vs. 47%; P = .01), posteroseptal substrates (22% vs. 9%; P = .002), and ventricular substrates (12% vs. 1%; P < .0001). All cases of intra‐atrial reentrant tachycardia were HF. HF was associated with trans‐septal puncture (47% vs. 23%; P < .0001) though not when controlling for atrioventricular nodal reentrant tachycardia. LF was associated with cryoablation (56% vs. 17%; P < .0001).ConclusionsIn pediatric and congenital EP, ablation procedures using cryoablation and in patients with anatomically normal hearts are associated with LF. In accessory pathway ablation, HF was not associated with trans‐septal puncture.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111901/1/chd12213.pd

A family intervention to reduce delirium in hospitalzed ICU patients: a feasibility randomized controlled trial

Background: Family members could play an important role in preventing and reducing the development of delirium in Intensive Care Units (ICU) patients. This study sought to assess the feasibility of design and recruitment, and accept ability for family members and nurses of a family delivered intervention to reduce delirium in ICU patients. Method: A single centre randomised controlled trial in an Australian medical/surgical ICU was conducted. Sixty-one family members were randomised (29 in intervention and 32 in non-intervention group). Following instructions, the intervention comprised the family members providing orientation, or memory clues (family photographs, orientation to surroundings) to their relative each day. In addition, family members conducted sensory checks (vision and hearing with glasses and hearing aids); and 5 therapeutic or cognitive stimulation (discussing family life, reminiscing) daily. Eleven ICU nurses were interviewed to gain insight into the feasibility and acceptability of implementing the intervention from their perspective. Results: Recruitment rate was 28% of eligible patients (recruited n=90, attrition n=1). Following instruction by the research nurse the family member delivered the intervention which was assessed to be feasible and acceptable by family members and nurses. Protocol adherence could be improved with alternative data collection methods. Nurses considered the activities acceptable. Conclusion: The study was able to recruit, randomise, and retain family member participants. Further strategies are required to assess intervention fidelity and improve data collection

General duality for abelian-group-valued statistical-mechanics models

We introduce a general class of statistical-mechanics models, taking values in an abelian group, which includes examples of both spin and gauge models, both ordered and disordered. The model is described by a set of ``variables'' and a set of ``interactions''. A Gibbs factor is associated to each variable and to each interaction. We introduce a duality transformation for systems in this class. The duality exchanges the abelian group with its dual, the Gibbs factors with their Fourier transforms, and the interactions with the variables. High (low) couplings in the interaction terms are mapped into low (high) couplings in the one-body terms. The idea is that our class of systems extends the one for which the classical procedure 'a la Kramers and Wannier holds, up to include randomness into the pattern of interaction. We introduce and study some physical examples: a random Gaussian Model, a random Potts-like model, and a random variant of discrete scalar QED. We shortly describe the consequence of duality for each example.Comment: 26 pages, 2 Postscript figure

Lamellipodium extension and membrane ruffling require different SNARE-mediated trafficking pathways

<p>Abstract</p> <p>Background</p> <p>Intracellular membrane traffic is an essential component of the membrane remodeling that supports lamellipodium extension during cell adhesion. The membrane trafficking pathways that contribute to cell adhesion have not been fully elucidated, but recent studies have implicated SNARE proteins. Here, the functions of several SNAREs (SNAP23, VAMP3, VAMP4 and syntaxin13) are characterized during the processes of cell spreading and membrane ruffling.</p> <p>Results</p> <p>We report the first description of a SNARE complex, containing SNAP23, syntaxin13 and cellubrevin/VAMP3, that is induced by cell adhesion to an extracellular matrix. Impairing the function of the SNAREs in the complex using inhibitory SNARE domains disrupted the recycling endosome, impeded delivery of integrins to the cell surface, and reduced haptotactic cell migration and spreading. Blocking SNAP23 also inhibited the formation of PMA-stimulated, F-actin-rich membrane ruffles; however, membrane ruffle formation was not significantly altered by inhibition of VAMP3 or syntaxin13. In contrast, membrane ruffling, and not cell spreading, was sensitive to inhibition of two SNAREs within the biosynthetic secretory pathway, GS15 and VAMP4. Consistent with this, formation of a complex containing VAMP4 and SNAP23 was enhanced by treatment of cells with PMA. The results reveal a requirement for the function of a SNAP23-syntaxin13-VAMP3 complex in the formation of lamellipodia during cell adhesion and of a VAMP4-SNAP23-containing complex during PMA-induced membrane ruffling.</p> <p>Conclusions</p> <p>Our findings suggest that different SNARE-mediated trafficking pathways support membrane remodeling during ECM-induced lamellipodium extension and PMA-induced ruffle formation, pointing to important mechanistic differences between these processes.</p

Management of Complications Caused By a Massive Left Ventricle Tumor in a Neonate

We report a case of a neonate born with a giant fibroma occupying the entirety of her left ventricle. Due to the extensive resection, her postoperative course was complicated by severely diminished left ventricular function and complete heart block necessitating extracorporeal support. Ultimately, cardiac resynchronization therapy was employed, after which the infant’s ventricular function gradually improved and she was successfully discharged to home

Filling the void: an optimized polymicrobial interkingdom biofilm model for assessing novel antimicrobial agents in endodontic infection

There is a growing realization that endodontic infections are often polymicrobial, and may contain Candida spp. Despite this understanding, the development of new endodontic irrigants and models of pathogenesis remains limited to mono-species biofilm models and is bacterially focused. The purpose of this study was to develop and optimize an interkingdom biofilm model of endodontic infection and use this to test suitable anti-biofilm actives. Biofilms containing Streptococcus gordonii, Fusobacterium nucleatum, Porphyromonas gingivalis, and Candida albicans were established from ontological analysis. Biofilms were optimized in different media and atmospheric conditions, prior to quantification and imaging, and subsequently treated with chlorhexidine, EDTA, and chitosan. These studies demonstrated that either media supplemented with serum were equally optimal for biofilm growth, which were dominated by S. gordonii, followed by C. albicans. Assessment of antimicrobial activity showed significant effectiveness of each antimicrobial, irrespective of serum. Chitosan was most effective (3 log reduction), and preferentially targeted C. albicans in both biofilm treatment and inhibition models. Chitosan was similarly effective at preventing biofilm growth on a dentine substrate. This study has shown that a reproducible and robust complex interkingdom model, which when tested with the antifungal chitosan, supports the notion of C. albicans as a key structural component

The cytokine temporal profile in rat cortex after controlled cortical impact

Cerebral inflammatory responses may initiate secondary cascades following traumatic brain injury (TBI). Changes in the expression of both cytokines and chemokines may activate, regulate, and recruit innate and adaptive immune cells associated with secondary degeneration, as well as alter a host of other cellular processes. In this study, we quantified the temporal expression of a large set of inflammatory mediators in rat cortical tissue after brain injury. Following a controlled cortical impact (CCI) on young adult male rats, cortical and hippocampal tissue of the injured hemisphere and matching contralateral material was harvested at early (4, 12, and 24 hours) and extended (3 and 7 days) time points post-procedure. Naïve rats that received only anesthesia were used as controls. Processed brain homogenates were assayed for chemokine and cytokine levels utilizing an electrochemiluminescence-based multiplex ELISA platform. The temporal profile of cortical tissue samples revealed a multi-phasic injury response following brain injury. CXCL1, IFN-γ, TNF-α levels significantly peaked at four hours post-injury compared to levels found in naïve or contralateral tissue. CXCL1, IFN-γ, and TNF-α levels were then observed to decrease at least 3-fold by 12 hours post-injury. IL-1β, IL-4, and IL-13 levels were also significantly elevated at four hours post-injury although their expression did not decrease more than 3-fold for up to 24 hours post-injury. Additionally, IL-1β and IL-4 levels displayed a biphasic temporal profile in response to injury, which may suggest their involvement in adaptive immune responses. Interestingly, peak levels of CCL2 and CCL20 were not observed until after four hours post-injury. CCL2 levels in injured cortical tissue were significantly higher than peak levels of any other inflammatory mediator measured, thus suggesting a possible use as a biomarker. Fully elucidating chemokine and cytokine signaling properties after brain injury may provide increased insight into a number of secondary cascade events that are initiated or regulated by inflammatory responses

Enhancement in critical current density and irreversibility field of bulk MgB2 by C and CaCO3 co-addition

Paper ash, a source of C and CaCO3, was used for the first time as a cheap form of sub-micron particles for doping. 0–10 wt% of the ash was added to Mg + 2B and in situ reacted at 850 ◦C for 30 min in flowing Ar atmosphere. The CaCO3 decomposed and reacted with B to form CaB6 as an impurity phase. Also, the Tc and the a-axis lattice parameter decreased with increasing ash content, which suggests that C substitution at boron sites occurred. Enhancement of high-field Jc(H), Hirr(T ) and Hc2(T ) was observed with an optimum level of about 5 wt% ash additio