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Anomalous aortic origin of a coronary artery is the second leading cause of sudden cardiac arrest/death in young athletes in the United States of America. Limited data are available regarding family history in this patient population.
Patients were evaluated prospectively from 12/2012 to 02/2017 in the Coronary Anomalies Program at Texas Children’s Hospital. Relevant family history included the presence of CHD, sudden cardiac arrest/death, arrhythmia/pacemaker use, cardiomyopathy, and atherosclerotic coronary artery disease before the age of 50 years. The presence of one or more of these in 1st- or 2nd-degree relatives was considered significant.
Of 168 unrelated probands (171 patients total) included, 36 (21%) had significant family history involving 19 (53%) 1st-degree and 17 (47%) 2nd-degree relatives. Positive family history led to cardiology referral in nine (5%) patients and the presence of abnormal tests/symptoms in the remaining patients. Coronary anomalies in probands with positive family history were anomalous right (27), anomalous left (five), single right coronary artery (two), myocardial bridge (one), and anomalous circumflex coronary artery (one). Conditions present in their family members included sudden cardiac arrest/death (15, 42%), atherosclerotic coronary artery disease (14, 39%), cardiomyopathy (12, 33%), CHD (11, 31%), coronary anomalies (3, 8%), myocardial bridge (1, 3%), long-QT syndrome (2, 6%), and Wolff–Parkinson–White (1, 3%).
In patients with anomalous aortic origin of a coronary artery and/or myocardial bridges, there appears to be familial clustering of cardiac diseases in approximately 20% of patients, half of these with early occurrence of sudden cardiac arrest/death in the family.
OBJECTIVES/SPECIFIC AIMS: Clostridium difficile infection (CDI) is the most common cause of antibiotic-associated diarrhea and an increasingly common infection in children in both hospital and community settings. Between 20% and 30% of pediatric patients will have a recurrence of symptoms in the days to weeks following an initial infection. Multiple recurrences have been successfully treated with fecal microbiota transplantation (FMT), though the body of evidence in pediatric patients is limited primarily to case reports and case series. The goal of our study was to better understand practices, success, and safety of FMT in children as well as identify risk factors associated with a failed FMT in our pediatric patients. METHODS/STUDY POPULATION: This multicenter retrospective analysis included 373 patients who underwent FMT for CDI between January 1, 2006 and January 1, 2017 from 18 pediatric centers. Demographics, baseline characteristics, FMT practices, C. difficile outcomes, and post-FMT complications were collected through chart abstraction. Successful FMT was defined as no recurrence of CDI within 60 days after FMT. Of the 373 patients in the cohort, 342 had known outcome data at two months post-FMT and were included in the primary analysis evaluating risk factors for recurrence post-FMT. An additional six patients who underwent FMT for refractory CDI were excluded from the primary analysis. Unadjusted analysis was performed using Wilcoxon rank-sum test, Pearson χ2 test, or Fisher exact test where appropriate. Stepwise logistic regression was utilized to determine independent predictors of success. RESULTS/ANTICIPATED RESULTS: The median age of included patients was 10 years (IQR; 3.0, 15.0) and 50% of patients were female. The majority of the cohort was White (89.0%). Comorbidities included 120 patients with inflammatory bowel disease (IBD) and 14 patients who had undergone a solid organ or stem cell transplantation. Of the 336 patients with known outcomes at two months, 272 (81%) had a successful outcome. In the 64 (19%) patients that did have a recurrence, 35 underwent repeat FMT which was successful in 20 of the 35 (57%). The overall success rate of FMT in preventing further episodes of CDI in the cohort with known outcome data was 87%. Unadjusted predictors of a primary FMT response are summarized. Based on stepwise logistic regression modeling, the use of fresh stool, FMT delivery via colonoscopy, the lack of a feeding tube, and a lower number of CDI episodes before undergoing FMT were independently associated with a successful outcome. There were 20 adverse events in the cohort assessed to be related to FMT, 6 of which were felt to be severe. There were no deaths assessed to be related to FMT in the cohort. DISCUSSION/SIGNIFICANCE OF IMPACT: The overall success of FMT in pediatric patients with recurrent or severe CDI is 81% after a single FMT. Children without a feeding tube, who receive an early FMT, FMT with fresh stool, or FMT via colonoscopy are less likely to have a recurrence of CDI in the 2 months following FMT. This is the first large study of FMT for CDI in a pediatric cohort. These findings, if confirmed by additional prospective studies, will support alterations in the practice of FMT in children.
There has been a recent move in psychiatry towards the use of electronic discharge (e-discharge) summaries in an effort to improve the efficiency of communication between primary and secondary care, but there are little data on how this affects the quality of information exchanged.
To evaluate the quality of psychiatric discharge summaries before and after the introduction of the e-discharge summary system.
A retrospective analysis of 50 dictated discharge summaries from 1 January to 1 July 2010 and of 50 e-discharge summaries from 1 January to 1 July 2012, evaluating for the inclusion of 15 key items of clinical information.
The average total score of the dictated summaries (mean=9.5, s.d.=2.0) was significantly higher (p<0.001) than the e-discharge summaries (mean=6.7, s.d.=1.8). There were statistically significant differences in five of the standards: findings of physical examination (p<0.001), ICD-10 code (p<0.001), forensic history (p<0.001), alcohol history (p<0.001) and drug history (p<0.001).
Our results revealed a decline in the quality of discharge summaries following the introduction of an electronic system. The reasons for this are unclear and require further analysis. Specific suggestions will depend on the local need, but include improvements in software design and layout as well as better education and training.
Data were extracted from the case records of UK patients admitted with laboratory-confirmed influenza A(H1N1)pdm09. White and non-White patients were characterized by age, sex, socioeconomic status, pandemic wave and indicators of pre-morbid health status. Logistic regression examined differences by ethnicity in patient characteristics, care pathway and clinical outcomes; multivariable models controlled for potential confounders. Whites (n = 630) and non-Whites (n = 510) differed by age, socioeconomic status, pandemic wave of admission, pregnancy, recorded obesity, previous and current smoking, and presence of chronic obstructive pulmonary disease. After adjustment for a priori confounders non-Whites were less likely to have received pre-admission antibiotics [adjusted odds ratio (aOR) 0·43, 95% confidence interval (CI) 0·28–0·68, P < 0·001) but more likely to receive antiviral drugs as in-patients (aOR 1·53, 95% CI 1·08–2·18, P = 0·018). However, there were no significant differences by ethnicity in delayed admission, severity at presentation for admission, or likelihood of severe outcome.
Small scale explosively driven fragmentation experiments have been performed on Aluminum (Al)-Tungsten (W) granular composite rings processed using cold isostatic compression of Al and W powders with a particle size of 4-30 microns. Fragments collected from the experiments had a maximum size of the order of a few hundred micrometers. This is a dramatic reduction in the fragment size when compared to the 1-10 mm typical for a homogeneous material such as solid aluminum under similar loading conditions. Numerical simulations of the experiment were performed to elucidate the mechanisms of fragmentation that were responsible for this shift in fragmentation size scales. Simulations were performed with a significantly stronger explosive driver to examine how the mechanisms of fragmentation change when the detonation pressure increases.
To investigate predictive factors of complete obliteration following treatment with linac-based stereotactic radiosurgery for intracerebral arteriovenous malformations.
Archived plans for 48 patients treated at the British Columbia Cancer Agency and who underwent post-treatment digital subtraction angiography to assess obliteration were studied. Actuarial estimates of obliteration were calculated using the Kaplan-Meier method. Univariate and multivariate Cox proportional hazards models were used for analysis of incidence of obliteration. Log-rank test was used to search for parameters associated with obliteration.
Complete nidus obliteration was achieved in 38/48 patients (79.2%). Actuarial rate of obliteration was 75.9% at 4 years (95% confidence interval 63.1%-88.6%). On univariate analysis, prescribed dose to the margin (p=0.002) and dose to isocentre (p=0.022) showed statistical significance. No parameters were significant in a multivariate model. According to the log-rank test, prescribed dose to the margin of >20 Gy (p=0.004) and dose to the isocentre of >25 Gy (p=0.004) were associated with obliteration.
Reported series in the literature suggest a number of different factors are predictive of complete obliteration of arteriovenous malformations following radiosurgery. However, differing definitions of volume and complete obliteration makes direct comparison between series difficult. This study demonstrates that complete obliteration of the nidus following linear accelerator-based stereotactic radiosurgery for arteriovenous malformations appears to be most closely related to the prescribed marginal dose. In particular, a marginal dose of >20Gy is strongly associated with obtaining complete obliteration of the nidus.
The extremely high surface areas required for supercapacitors has limited the use of metal based electrodes, despite the other advantages such electrodes might have. Self-assembling surfactants and block co-polymers can be used as templates to produce nanostructured thin films that readily give 60-140 fold increases in surface area on both planar and three-dimensional substrates. However, even when relatively high surface area porous metal substrates such as nickel foam are used as a starting point, the resultant material still has surface area density well short of that available in other types of materials. Micro-emulsions offer a method of generating microstructure that bridges the gap between the 100 micron scale structures of foamed metals and the 10-50 nm scale structure of self-assembling block co-polymers. Electrodeposition of nickel and cobalt from micro-emulsions of Tween surfactants gives rise to structure on the 0.1-10 micron length scale. The scale of the microstructure is strongly influenced by the metal ion concentration and the potential at which the electrodeposition. The nature of the metal ion also strongly effects the ease with which the microstructure can be generated and the distribution of the microstructured film on foamed nickel electrodes. For microstructured nickel films ten fold surface area increases can be achieved. The microstructured films are expected to be compatible with a number of the nanostructuring methods to yield cumulative surface area increases of 1000-2000 fold.
Hafnium nitride films were deposited by ion-beam sputtering, and characterized for their composition, electrical, structural, mechanical and optical characteristics. Films were found to vary widely in their properties, based upon the parameters under which they were deposited. The films were found to have a nitrogen to hafnium ratio of up to 1.45:1, resistivity varying from 10−2 to 105 Ω-cm, as well as widely variable optical characteristics, depending on process variables. Structural characterization of the dielectric phase HfNx (x>l) material by X-ray and electron diffraction reveals a distortion of the hafnium mononitride rock salt structure with increasing amounts of nitrogen, in accordance with previous findings. Infrared spectroscopic characterization of the thin film dielectric phase hafnium nitride optical properties reveals the likely existence of multiple bonding between nitrogen in the material.
Much interest has been shown in the use of tetrahedral amorphous carbon (ta-C) deposited by filtered cathodic arc as an inexpensive, easily produced, wide band-gap semiconductor in the fabrication of electronic devices. There has, however, been limited success in producing devices with properties that might make its use in electronic applications commercially viable, which in part may be due to the high density of electronic trap states as reflected in ta-C's rather high ESR signal of ∼ 1020 spin/g. Recent results at the University of Sydney suggest, however, that a new range of possibilities exist in the utilisation of these traps as a means of producing nonvolatile digital information storage. Devices with write times of 100 μs, read times of 100 ns, and effective memory retention times approaching 1 year, have been fabricated.
Carbon films deposited by filtered cathodic arc show a high compressive stress which limits their thickness because of delamination. We study three methods of relieving the stress in these films. We first determine the dependence of the stress on DC bias up to bias voltages of 1200V and show that the formula of Davis provides a good fit to the data including the stress maximum in the region of 150–200V and the progressive decrease in stress at higher voltages. In the second method, plasma immersion ion implantation (PIII) was used to create multilayer of alternating high density, high stress (PIII on) films and lower density, low stress (PIII off) films. This method enabled thicker structures to be produced. In the third method we made multilayers using amorphous silicon and carbon layers. Annealing of these layers showed that the stress could be reduced to very low values because of the ability of the silicon layers to absorb compressive stress by contracting after the annealing step. The microstructural effects of PIII were studied by transmission and scanning electron microscopy.
Gold nanoparticles were linked to ZnO films and nanowires using phosphonic and carboxylic acid ligands. TEM and STEM-HAADF characterization showed that gold nanoparticles modified with both types of ligands anchored on ZnO nanowire surfaces as well as on ZnO films. After removing the ligands from the interface between ZnO nanowires and supported gold nanoparticles, the electric conductivity in the presence of methanol vapor increased by 100 times as compared to the bare ZnO nanowire, which suggested enhanced-catalytic effects due to the hybrid structure. In addition, ZnO/Au nanomaterials were synthesized by linking ZnO nanoparticles and carboxylate-functionalized gold nanoparticles in solution. UV-vis characterization showed both the bandgap absorption from ZnO and the plasmon absorption from gold nanoparticles. Formation of hybrid nanosystems like these using organic ligands as linkers not only can lead to materials with enhanced properties but also minimize the waste of precious elements because the assembly process is an additive, rather than subtractive, process.
We report on a pair of MSP (Mathematics & Science Partnership) START pilot projects designed to identify nanoscience experiments that will fit within the Alabama course of study for use in Alabama K-12 classrooms. As part of the first project we are testing the development, refinement and evaluation of an activity already partly developed. The form of this activity has had input from a focus group of RETs who were tasked to provide input into the activity and how it can be matched to components of the Alabama Course of Study. This activity consists of using sparks generated by abrasion of misch metal by sand paper of different grit size. Different grit sizes produce metal particles of different sizes, resulting in sparks of different size and length. If done in a dry box no sparks are produced and the powder left is not pyrophoric, demonstrating that high surface area, heat and oxygen are all required to produce sparks. SEM characterization of the powder allows the particle sizes to be determined, giving the correlation between size, grit size and spark track length. The activity was tested on groups of middle school science campers at McWane Science Center, and after evaluation, further modified to increase student interest and impact. The activity was then tested on grades 6-8 in a middle school classroom by a graduate student/undergraduate student team.