Laser arytenoidectomy in children with bilateral vocal fold immobility

Bilateral vocal fold immobility in children is a challenging problem because a balance between good airway and voice quality has to be achieved. Surgery to improve the airway is often postponed or avoided because of fear of losing the voice. In this study our results of laser arytenoidectomy in children are described. This was a retrospective case notes review at a tertiary level paediatric ENT department. The six patients in this case series ranged from nine to 16 years old at the time of laser arytenoidectomy. Post-operative airway and voice quality were assessed. All children in the series had an adequate post-operative airway. Four of these patients had tracheostomies pre-operatively and achieved decannulation. All six patients rated their post-operative voice as better than pre-operatively. This is principally due to increased loudness associated with increased airflow through the larynx, particularly after tracheostomy decannulation. It is recommended that special care should be taken not to disturb the anterior two thirds of the vocal fold during the surgery in order to achieve a good post-operative voice outcome

Causes of deafness in East London Bangladeshi children.

The aim of this study was to examine the causes of sensorineural hearing loss in the Bangladeshi population resident in East London. Almost all of this population originates from Sylhet, a province in Bangladesh. The study was conducted at a community based audiology clinic and tertiary level genetics department. One hundred and fifteen families (134 patients) were ascertained 11 families declined to participate and 4 families could not be contacted. All children of Bangladeshi ethnic origin with bilateral sensorineural hearing loss more than 40dB in the better hearing ear were included in this study. Information on all these patients was collected from their case notes. For the 67 patients in whom the cause of deafness was not clear from the records or unknown (or non- syndromic deafness), families were seen in the research clinic. The prevalence of deafness >40db in Bangladeshi children under 16 years of age in East London was calculated to be approximately 3.86 per 1000 (95%CI: 3.24, 4.47). This is nearly 2.3 times the national average. Parents were consanguineous in 35 out of 105 families (33.3%) in which this information was available. On calculating the prevalence of deafness in the Bangladeshi children belonging to non-consanguineous families, the prevalence falls to 2.72 per 1000 (95%CI: 2.10, 3.34). Genetic causes appear to be the most common cause of deafness in Bangladeshi population in 59.6% patients. Environmental causes were responsible for hearing loss in 18.5% patients and in 21.8% cases the cause of deafness was undetermined. Of the deafness due to genetic causes, 57.7% were non-syndromic, 25.3% syndromic and 16.9% were chromosomal. The single most common cause of sensorineural hearing loss in the Bangladeshi population in this study was due to mutations in the GJB2 gene (Connexin 26) in 14 of these families. The mutations in GJB2 in this population were W24X, IVS1 + 1G->A, M1V, V95M and W77X. W24X was the most common mutation seen in 40% (8/20) patients. Genetic causes are the common cause of deafness in subjects of Bangladeshi origin and 29.8% children with non-syndromic deafness were positive for mutations in GJB2

The Galois Complexity of Graph Drawing: Why Numerical Solutions are Ubiquitous for Force-Directed, Spectral, and Circle Packing Drawings

Many well-known graph drawing techniques, including force directed drawings, spectral graph layouts, multidimensional scaling, and circle packings, have algebraic formulations. However, practical methods for producing such drawings ubiquitously use iterative numerical approximations rather than constructing and then solving algebraic expressions representing their exact solutions. To explain this phenomenon, we use Galois theory to show that many variants of these problems have solutions that cannot be expressed by nested radicals or nested roots of low-degree polynomials. Hence, such solutions cannot be computed exactly even in extended computational models that include such operations.Comment: Graph Drawing 201

Unconventional machine learning of genome-wide human cancer data

Recent advances in high-throughput genomic technologies coupled with exponential increases in computer processing and memory have allowed us to interrogate the complex aberrant molecular underpinnings of human disease from a genome-wide perspective. While the deluge of genomic information is expected to increase, a bottleneck in conventional high-performance computing is rapidly approaching. Inspired in part by recent advances in physical quantum processors, we evaluated several unconventional machine learning (ML) strategies on actual human tumor data. Here we show for the first time the efficacy of multiple annealing-based ML algorithms for classification of high-dimensional, multi-omics human cancer data from the Cancer Genome Atlas. To assess algorithm performance, we compared these classifiers to a variety of standard ML methods. Our results indicate the feasibility of using annealing-based ML to provide competitive classification of human cancer types and associated molecular subtypes and superior performance with smaller training datasets, thus providing compelling empirical evidence for the potential future application of unconventional computing architectures in the biomedical sciences

An open-label pilot single-subject study to monitor the impact of a Food-Based enteral formula on faecal short-chain fatty acid concentrations in children admitted to intensive care with sepsis

Background: Non-digestible dietary fiber undergoes fermentation by the intestinal microbiota to produce short-chain fatty acids (SCFAs). Intestinal SCFAs control the production of T-helper cells, antibodies and are involved in maintaining homeostasis of the mucosal system. Sepsis is the leading cause of mortality in hospitalised children and is treated with antibiotics which disrupts the normal maturation of the microbiome causing dysbiosis. This study assessed the impact of a high-fibre Food-Based formula on feed tolerance and faecal SCFA concentrations in children admitted to intensive care with sepsis. Methods: An open-label single-subject study was based on repeated observations over 14 days in children admitted to intensive care with sepsis who commenced a high-fiber Food-Based enteral formula Compleat®Paediatric, (Nestle Health Science). Stool samples were collected to measure SCFA concentrations (acetate, butyrate and propionate). A Wilcoxon Signed-Rank test was used to measure change in SCFA concentrations. Other data collection included feed tolerance, anthropometrics, antibiotic administration and inflammatory markers. Results: Twenty children with sepsis were recruited over six months. The mean age was 10.8 years (±5.6 years SD). The most common sepsis-related organ failure was the respiratory tract (50 %). The mean duration of mechanical ventilation was 9 days (±4 SD), 25 % of children were treated with more than two antibiotics during their time in intensive care. Faecal propionate and butyrate concentrations were maintained during the children's time in intensive care. Stool frequency reduced from 2.6 per day (±1.08 SD) at baseline to 1.2 per day (±0.45 SD) after one week in intensive care (p < 0.004). Conclusion: In this pilot study children admitted to intensive care with sepsis tolerated a Food-Based formula. Faecal butyrate and propionate concentrations were maintained whilst feeding on a high fiber Food-Based formula. Further research is warranted to assess whether a Food-Based formula is superior to a standard enteral formula in preserving the intestinal microbiota, thereby mitigating gastrointestinal complications associated with antibiotic-related dysbiosis

Quantification of fluoroquinolone uptake through the outer membrane channel OmpF of Escherichia coli

This is the author accepted manuscript. The final version is available from the publisher via the DOI in this record.Decreased drug accumulation is a common cause of antibiotic resistance in microorganisms. However, there are few reliable general techniques capable of quantifying drug uptake through bacterial membranes. We present a semiquantitative optofluidic assay for studying the uptake of autofluorescent drug molecules in single liposomes. We studied the effect of the Escherichia coli outer membrane channel OmpF on the accumulation of the fluoroquinolone antibiotic, norfloxacin, in proteoliposomes. Measurements were performed at pH 5 and pH 7, corresponding to two different charge states of norfloxacin that bacteria are likely to encounter in the human gastrointestinal tract. At both pH values, the porins significantly enhance drug permeation across the proteoliposome membranes. At pH 5, where norfloxacin permeability across pure phospholipid membranes is low, the porins increase drug permeability by 50-fold on average. We estimate a flux of about 10 norfloxacin molecules per second per OmpF trimer in the presence of a 1 mM concentration gradient of norfloxacin. We also performed single channel electrophysiology measurements and found that the application of transmembrane voltages causes an electric field driven uptake in addition to concentration driven diffusion. We use our results to propose a physical mechanism for the pH mediated change in bacterial susceptibility to fluoroquinolone antibiotics.This work was supported by a European Research Council (ERC) Grant (261101 Passmembrane) to UFK. JC acknowledges support from an Internal Graduate Studentship, Trinity College, Cambridge, and a Research Studentship from the Cambridge Philosophical Society. SP was supported by the Leverhulme Trust through an Early Career Fellowship. TM acknowledges support from the Konrad-Adenauer Foundation and the German National Merit Foundation. HB, YB and MW are part of the TRANSLOCATION consortium and have received support from the Innovative Medicines Joint Undertaking under grant agreement 115525, the European Union’s seventh framework program (FP7/2007-2013), and European Federation of Pharmaceutical Industries and Associates companies in-kind contribution

The Evolution of Data Fusion Methodologies Developed to Reconstruct Coronary Artery Geometry From Intravascular Imaging and Coronary Angiography Data: A Comprehensive Review

Understanding the mechanisms that regulate atherosclerotic plaque formation and evolution is a crucial step for developing treatment strategies that will prevent plaque progression and reduce cardiovascular events. Advances in signal processing and the miniaturization of medical devices have enabled the design of multimodality intravascular imaging catheters that allow complete and detailed assessment of plaque morphology and biology. However, a significant limitation of these novel imaging catheters is that they provide two-dimensional (2D) visualization of the lumen and vessel wall and thus they cannot portray vessel geometry and 3D lesion architecture. To address this limitation computer-based methodologies and user-friendly software have been developed. These are able to off-line process and fuse intravascular imaging data with X-ray or computed tomography coronary angiography (CTCA) to reconstruct coronary artery anatomy. The aim of this review article is to summarize the evolution in the field of coronary artery modeling; we thus present the first methodologies that were developed to model vessel geometry, highlight the modifications introduced in revised methods to overcome the limitations of the first approaches and discuss the challenges that need to be addressed, so these techniques can have broad application in clinical practice and research

Square patterns in Rayleigh-Benard convection with rotation about a vertical axis

We present experimental results for Rayleigh-Benard convection with rotation about a vertical axis at dimensionless rotation rates in the range 0 to 250 and upto 20% above the onset. Critical Rayleigh numbers and wavenumbers agree with predictions of linear stability analysis. For rotation rates greater than 70 and close to onset, the patterns are cellular with local four-fold coordination and differ from the theoretically expected Kuppers-Lortz unstable state. Stable as well as intermittent defect-free square lattices exist over certain parameter ranges. Over other ranges defects dynamically disrupt the lattice but cellular flow and local four-fold coordination is maintained.Comment: ReVTeX, 4 pages, 7 eps figures include