Echocardiographic assessment and percutaneous closure of multiple atrial septal defects

Percutaneous coronary intervention can be associated with distal embolization of thrombotic material causing myocardial necrosis and infarction. We discuss the role of intravascular imaging to guide the use of a distal protection device by describing the outcome of a young woman presenting with non-ST elevation myocardial infarction. Coronary angiography demonstrated an isolated minor stenosis in the proximal left anterior descending coronary artery with slight haziness beyond the lesion. Intravascular ultrasound confirmed an extensive thrombus overlying a bulky atherosclerotic plaque. A distal filter wire was therefore successfully used to reduce the risk of distal embolization. The use of intravascular ultrasound in patients presenting with acute coronary syndrome may reveal large thrombi that are difficult to image using conventional angiographic techniques. Intravascular ultrasound can therefore be used as a tool to select lesions requiring distal protection.     

Sequence variations in small-subunit ribosomal RNAs of Hartmannella vermiformis and their phylogenetic implications

Evidence of associations between free-living amoebas and human disease has been increasing in recent years. Knowledge about phylogenetic relationships that may be important for the understanding of pathogenicity in the genera involved is very limited at present. Consequently, we have begun to study these relationships and report here on the phylogeny of Hartmannella vermiformis, a free-living amoeba that can harbor the etiologic agent of Legionnaires' disease. Our analysis is based on studies of small-subunit ribosomal RNA genes (srDNA). Nucleotide sequences were determined for nuclear srDNA from three strains of H. vermiformis isolated from the United Kingdom, Germany, and the United States. These sequences then were compared with a sequence previously obtained for a North American isolate by J. H. Gunderson and M. L. Sogin. The four genes are 1,840 bp long, with an average GC content of 49.6%. Sequence differences among the strains range are 0.38%-0.76%. Variation occurs at 19 positions and includes 2 single-base indels plus 14 monotypic and 3 ditypic single-base substitutions. Variation is limited to eight helix/loop structures according to a current model for srRNA secondary structure. Parsimony, distance, and bootstrap analyses used to examine phylogenetic relationships between the srDNA sequences of H. vermiformis and other eukaryotes indicated that Hartmannella sequences were most closely related to those of Acanthamoeba and the alga Cryptomonas. All ditypic sites were consistent with a separation between European and North American strains of Hartmannella, but results of other tests of this relationship were statistically inconclusive.      

The identification of glycoproteins associated with elastic-tissue microfibrils.

Cell cultures derived from foetal bovine ligamentum nuchae accumulate extracellular fibrils morphologically identical with elastic-tissue microfibrils. Two glycoproteins synthesized by the ligament cells are closely related to the matrix microfibrils as assessed by immunological and chemical extraction techniques.     

Human alpha-galactosidase A: characterization of the N-linked oligosaccharides on the intracellular and secreted glycoforms overexpressed by Chinese hamster ovary cells

Human alpha-galactosidase A (alpha-Gal A) is the lysosomal glycohydrolase that cleaves the terminal alpha-galactosyl moieties of various glycoconjugates. Overexpression of the enzyme in Chinese hamster ovary (CHO) cells results in high intracellular enzyme accumulation and the selective secretion of active enzyme. Structural analysis of the N -linked oligosaccharides of the intracellular and secreted glycoforms revealed that the secreted enzyme's oligosaccharides were remarkably heterogeneous, having high mannose (63%), complex (30%), and hybrid (5%) structures. The major high mannose oligosaccharides were Man5-7GlcNAc2 species. Approximately 40% of the high mannose and 30% of the hybrid oligosaccharides had phosphate monoester groups. The complex oligosaccharides were mono-, bi- , 2,4-tri-, 2,6-tri- and tetraantennary with or without core-region fucose, many of which had incomplete outer chains. Approximately 30% of the complex oligosaccharides were mono- or disialylated. Sialic acids were mostly N -acetylneuraminic acid and occurred exclusively in alpha2, 3-linkage. In contrast, the intracellular enzyme had only small amounts of complex chains (7.7%) and had predominantly high mannose oligosaccharides (92%), mostly Man5GlcNAc2 and smaller species, of which only 3% were phosphorylated. The complex oligosaccharides were fucosylated and had the same antennary structures as the secreted enzyme. Although most had mature outer chains, none were sialylated. Thus, the overexpression of human alpha-Gal A in CHO cells resulted in different oligosaccharide structures on the secreted and intracellular glycoforms, the highly heterogeneous secreted forms presumably due to the high level expression and impaired glycosylation in the trans- Golgi network, and the predominately Man5-7GlcNAc2 cellular glycoforms resulting from carbohydrate trimming in the lysosome.      

Tyrosine phosphorylation of myosin heavy chain during skeletal muscle differentiation: an integrated bioinformatics approach

Background  

Previously it has been shown that insulin-mediated tyrosine phosphorylation of myosin heavy chain is concomitant with enhanced association of C-terminal SRC kinase during skeletal muscle differentiation. We sought to identify putative site(s) for this phosphorylation event.     

Influence of nanofibers on growth and gene expression of human tendon derived fibroblast

Background  

Rotator cuff tears are a common and frequent lesion especially in older patients. The mechanisms of tendon repair are not fully understood. Common therapy options for tendon repair include mini-open or arthroscopic surgery. The use of growth factors in experimental studies is mentioned in the literature. Nanofiber scaffolds, which provide several criteria for the healing process, might be a suitable therapy option for operative treatment. The aim of this study was to explore the effects of nanofiber scaffolds on human tendon derived fibroblasts (TDF's), as well as the gene expression and matrix deposition of these fibroblasts.