Arrhythmia Detection in Pediatric Patients: ECG Quality and Diagnostic Yield of a Patient-Triggered Einthoven Lead-I Event Recorder (Zenicor EKG-2™).

Symptoms that may be caused by arrhythmia are common in pediatric outpatient departments, though it remains challenging to reveal paroxysmal tachycardia. This investigation evaluated prospectively the quality and diagnostic yield of a newly available handheld patient-activated event recorder (ER) in children. In 226 children (pts) aged 0-17 years with or without congenital heart defects, pacemaker/ICDs or arrhythmia, a lead-I ER ECG was created. ER ECGs were recorded by pressing the patients' thumbs on the device and were analyzed in comparison with a lead-12 ECG, as gold standard. Event recording and data transmission were possible in all cases. ECG quality of the ER showed a high accordance in measuring heart rate (ICC = 0.962), duration of QRS complexes (κ = 0.686), and PR interval (ICC = 0.750) (p < 0.001) although P wave detection remained challenging (p = 0.120). 36 % (n = 82) of the pts had heart rhythm disturbances. The ER yielded 92 % sensitivity in diagnosing supraventricular tachycardia plus 77 % sensitivity and 92 % specificity in identifying abnormal ECGs. In children, the application of the tested ER was suitable. ECGs of good quality could be performed and transmitted easily, and also complex arrhythmia analysis was possible. This ER is an excellent diagnostic device for the detection and exclusion of tachycardia in children.

Mucin adhesion of serial cystic fibrosis airways Pseudomonas aeruginosa isolates.

The chronic airway infections with Pseudomonas aeruginosa are the major co-morbidity in people with cystic fibrosis (CF). Within CF lungs, P. aeruginosa persists in the conducting airways together with human mucins as the most abundant structural component of its microenvironment. We investigated the adhesion of 41 serial CF airway P. aeruginosa isolates to airway mucin preparations from CF sputa. Mucins and bacteria were retrieved from five modulator-naïve patients with advanced CF lung disease. The P. aeruginosa isolates from CF airways and non-CF reference strains showed a strain-specific signature in their adhesion to ovine, porcine and bovine submaxillary mucins and CF airway mucins ranging from no or low to moderate and strong binding. Serial CF clonal isolates and colony morphotypes from the same sputum sample were as heterogeneous in their affinity to mucin as representatives of other clones thus making 'mucin binding' one of the most variable intraclonal phenotypic traits of P. aeruginosa known to date. Most P. aeruginosa CF airway isolates did not adhere more strongly to CF airway mucins than to plastic surfaces. The strong binders, however, exhibited a strain-specific affinity gradient to O-glycans, CF airway and mammalian submaxillary mucins.

Intraclonal diversity of the Pseudomonas aeruginosa cystic fibrosis airway isolates TBCF10839 and TBCF121838: distinct signatures of transcriptome, proteome, metabolome, adherence and pathogenicity despite an almost identical genome sequence.

Microevolution of closely related Pseudomonas aeruginosa was compared in the clone TB strains TBCF10839 and TBCF121838 which had been isolated from two unrelated individuals with cystic fibrosis who had acquired clone TB during a local outbreak. Compared with the strain PAO1 reference sequence the two clone TB genomes shared 23 155 nucleotide exchanges, 32 out-of-frame indels in the coding region and another repertoire of replacement and genomic islands such as PAGI-1, PAGI-2, PAGI-5, LESGI-1 and LES-prophage 4. Only TBCF121838 carried a genomic island known from Ralstonia pickettii. Six of the seven strain-specific sequence variations in the core genome were detected in genes affecting motility, biofilm formation or virulence, i.e. non-synonymous nucleotide substitutions in mexS, PA3729, PA5017, mifR, a frameshift mutation in pilF (TBCF121838) and an intragenic deletion in pilQ (TBCF10839). Despite their almost identical genome sequence the two strains differed strongly from each other in transcriptome and metabolome profiles, mucin adherence and phagocytosis assays. TBCF121838 was susceptible to killing by neutrophils, but TBCF10839 could grow in leucocytes. Microevolution in P. aeruginosa apparently can generate novel complex traits by few or even single mutations provided that predisposing mutational events had occurred before in the clonal lineage.

Diagnosis of a terminal deletion of 4p with duplication of Xp22.31 in a patient with findings of Opitz G/BBB syndrome and Wolf-Hirschhorn syndrome.

Opitz G/BBB syndrome (OS) is a congenital midline malformation syndrome characterized by hypertelorism, hypospadias, cleft lip/palate, laryngotracheoesophageal abnormalities, imperforate anus, developmental delay and cardiac defects. The X-linked form is caused by mutations in the MID1 gene, while no gene has yet been identified for the autosomal dominant form. Here, we report on a 15-year-old boy who was referred for MID1 mutation analysis with findings typical of OS, including apparent hypertelorism, hypospadias, a history of feeding difficulties, dysphagia secondary to esophageal arteria lusoria, growth retardation and developmental delay. No MID1 mutation was found, but subsequent sub-megabase resolution array CGH unexpectedly documented a 2.34 Mb terminal 4p deletion, suggesting a diagnosis of WHS, and a duplication in Xp22.31. Wolf-Hirschhorn syndrome (WHS) is a contiguous gene deletion syndrome involving terminal chromosome 4p deletions, in particular 4p16.3. WHS is characterized by typical facial appearance ("Greek helmet facies"), mental retardation, congenital hypotonia, and growth retardation. While the severity of developmental delay in this patient supports the diagnosis of WHS rather than OS, this case illustrates the striking similarities of clinical findings in seemingly unrelated syndromes, suggesting common or interacting pathways at the molecular and pathogenetic level. This is the first report of arteria lusoria (esophageal vascular ring) in a patient with WHS.

Adherence of Pseudomonas aeruginosa to cystic fibrosis buccal epithelial cells.

Pseudomonas aeruginosa cystic fibrosis buccal adherence assay http://ow.ly/lPtB306VKIQ.

Enzymatic Degradation of Films, Particles, and Nonwoven Meshes Made of a Recombinant Spider Silk Protein.

The performance of biomaterials in vivo is largely influenced by their stability and the rate and extent to which they degrade. Materials for tissue engineering applications, for example, have to be mechanically stable to support cell adhesion and proliferation without collapsing. On the other hand they need to be replaced gradually by native extracellular matrix and have to be (slowly) biodegradable. Therefore, it is of critical importance to be able to tune the degradation behavior of a biomaterial. Recombinantly produced spider silk proteins have been shown to be versatile biopolymers for medical applications. They can be processed into a variety of morphologies, and by chemical or genetic modification the properties can be adjusted to specific demands. Furthermore, in vivo experiments confirmed the lack of immunological reactions toward certain spider silks. In this study the degradation behavior of the recombinant spider silk protein eADF4(C16) in solution as well as processed into particles, films and nonwoven meshes was analyzed, and the impact of cross-linking of the scaffolds was assessed thereon. In addition to two bacterial proteolytic model enzymes, protease type XIV from Streptomyces griseus (PXIV) and collagenase type IA from Clostridium histolyticum (CHC) used in all experiments, several recombinant human matrix metalloproteinases (MMPs) and one elastase were used in studying degradation of soluble eADF4(C16). For soluble eADF4(C16) all degradation kinetics were similar. In case of eADF4(C16) scaffolds significant differences were observable between PXIV and CHC. All scaffolds were more stable toward proteolytic degradation in the presence of CHC than in the presence of PXIV. Further, particles were degraded significantly faster than films, and nonwoven meshes showed the highest proteolytic stability. Chemical cross-linking of the scaffolds led to a decrease in both degradation rate and extent.

Enhanced cellular uptake of engineered spider silk particles.

Drug delivery systems allow tissue/cell specific targeting of drugs in order to reduce total drug amounts administered to an organism and potential side effects upon systemic drug delivery. Most drug delivery systems are polymer-based, but the number of possible materials is limited since many commercially available polymers induce allergic or inflammatory responses or lack either biodegradability or the necessary stability in vivo. Spider silk proteins represent a new class of (bio)polymers that can be used as drug depots or drug delivery systems. The recombinant spider silk protein eADF4(C16), which can be processed into different morphologies such as particles, films, or hydrogels, has been shown to fulfil most criteria necessary for its use as biomaterial. Further, eADF4(C16) particles have been shown to be well-suited for drug delivery. Here, a new method was established for particle production to reduce particle size and size distribution. Importantly, cellular uptake of these particles was shown to be poor in HeLa cells. Therefore, variants of eADF4(C16) with inversed net charge or incorporated cell penetrating peptides and receptor interacting motifs were tested, showing much better cellular uptake. Interestingly, uptake of all silk variant particles was mainly achieved by clathrin-mediated endocytosis.

FT-IR spectroscopic characteristics of differently cultivated Bacillus subtilis.

Bacillus subtilis is an aerobic endospore forming bacterium widely spread in different environments. Because it represents a biological agent of some health relevance, its rapid detection and identification is highly desirable. By using FT-IR spectroscopy for this purpose slightly different characteristics were obtained from cell mass grown in differently composed cultural media, and harvested in different phases of bacterial growth. If cultivated uniformly, i.e., 24h at 30 degrees C in a minimum-strength nutrient broth, cell mass of B. subtilis delivered a well differentiated spectrum with major absorption bands of nucleic acid structures at 3300cm(-1), cell wall constituents at 3000-2800cm(-1), proteinaceous structures at 1660, 1544 and 1235cm(-1), and some aliphatic structural units at 1080cm(-1). Attenuated total reflectance, and absorption/transmission scanning techniques, delivered structurally identical spectra but those obtained by the former technique were more expressed.