Surface reconstruction using Delaunay triangulation for applications in life sciences

The Delaunay triangulation is an established method to define neighborhood relations in multi-particle systems. In particular, this method was employed for interacting multi-cellular systems in Biology. The extension of this method to a sub-cellular level that considers the membrane and the inner structure of cells is not straight forward and subject of this article. It is the objective to use a three-dimensional Delaunay-triangulation as a basis for the definition of a triangulation of a subset of particles that form a surface.An essential problem of this objective is the conservation of the number of particles belonging to the surface. This excludes established surface reconstruction algorithms. The presented algorithm allows the definition of a triangulation within a subset of particles attributed to a surface without the deletion of particles. A particular challenge is the deletion of connection that infer three-dimensional structures in the surface. The presented method is suitable for many configurations. Its performance and its limitations are analyzed and discussed.The developed algorithm for the reconstruction of connections in a surface is suitable to be used for simulations of biological cells because of the inherent conservation of the number of particles attributed to the membrane.     

Individual and combined effects of subclinical doses of deoxynivalenol and fumonisins in piglets

Scope: Deoxynivalenol (DON) and fumonisins (FB) are the most frequently encountered mycotoxins produced by Fusarium species and most commonly co‐occur in animal diets. These mycotoxins were studied for their toxicity in piglets on several parameters including plasma biochemistry, organ histopathology and immune response. Methods and results: Twenty‐four 5‐wk‐old animals were randomly assigned to four different groups, receiving separate diets for 5 wk, a control diet, a diet contaminated with either DON (3 mg/kg) or FB (6 mg/kg) or both toxins. At days 4 and 16 of the trial, the animals were subcutaneously immunized with ovalbumin to assess their specific immune response. The different diets did not affect animal performance and had minimal effect on hematological and biochemical blood parameters. By contrast, DON and FB induced histopathological lesions in the liver, the lungs and the kidneys of exposed animals. The liver was significantly more affected when the two mycotoxins were present simultaneously. The contaminated diets also altered the specific immune response upon vaccination as measured by reduced anti‐ovalbumin IgG level in the plasma and reduced lymphocyte proliferation upon antigenic stimulation. Because cytokines play a key role in immunity, the expression levels of IL‐8, IL‐1β, IL‐6 and macrophage inflammatory protein‐1β were measured by RT‐PCR at the end of the experiment. The expression of these four cytokines was significantly decreased in the spleen of piglets exposed to multi‐contaminated diet. Conclusion: Taken together, our data indicate that ingestion of multi‐contaminated diet induces greater histopathological lesions and higher immune suppression than ingestion of mono‐contaminated diets.     

Preliminary results of muscle cuff cervicoplasty in the ewe for the treatment of urinary incontinence

We describe a childhood mitochondrial disorder in which the clinical symptoms began and remained confined to the gastrointestinal (GI) system during the first 4 y. Seizures heralded the onset of progressive encephalopathy at age 7. Peripheral neuropathy, retinitis pigmentosa, and neural deafness developed subsequently. Laboratory investigations disclosed elevated levels of plasma lactate, and a muscle biopsy revealed ragged red fibers lacking cytochrome c oxidase activity and diminished levels of respiratory chain enzyme complexes. Molecular genetic tests failed to show any of the previously reported pathogenic mitochondrial DNA (mtDNA) mutations. We therefore screened the whole mitochondrial genome by coupling restriction digestions with single-strand conformational polymorphism (SSCP) patterns. We identified a unique SSCP in the segment that encompassed the tRNA(Lys) gene, and direct sequencing of this segment revealed a G-->A transition at an evolutionarily conserved nucleotide at mtDNA position 8313. This G8313A transition was heteroplasmic in muscle and fibroblasts of the patient, but was absent in the white blood cells and platelets from his maternal relatives. This report illustrates how GI symptoms can be the initial manifestation in a mitochondrial disorder and suggests that mitochondrial dysfunction should be considered in differentials of unexplained chronic GI symptoms, especially when lactic acidosis or other unrelated clinical signs or symptoms are present.     

Subcutaneous administration of interleukin-2 in ambulatory treatment of patients with metastatic renal cancer. Three-year results of the SCAPP I program

Angina, myocardial infarction, and sudden cardiac death are associated with thrombus formation in coronary arteries. It is generally believed that these conditions benefit from long-term exercise. However, the evidence for such amelioration or prevention is inconclusive and so is the mechanism through which long-term exercise exerts its beneficial effect on various ischaemic conditions. Because of the thrombotic events, the effects of exercise on platelet reactivity, blood coagulation and fibrinolysis have been extensively studied, but the findings are not consistent (1-9). This is mainly due to methodological problems. Analysis of platelet response to a variety of agonists and the dozen of coagulation and fibrinolysis variables makes the assessment of the overall platelet function, coagulation and fibrinolysis status extremely difficult.     

Effect of microencapsulation on survival of Lactobacillus plantarum in simulated gastrointestinal conditions, refrigeration, and yogurt

In the present research the survival of free and microencapsulated cells of a new strain of Lactobacillus plantarum BL011 under stress conditions was tested in sodium alginate or pectin, coated with sodium alginate or chitosan. Results for the simulated gastrointestinal medium (SGT) showed no change in viability of cells in relation to the control. However, the simulated gastric medium (GM) drastically reduced the viability under the tested conditions, with no significant differences between free and immobilized cells. Under refrigerated storage viability of immobilized cells were greatly enhanced compared to the free microorganisms, and the treatments showing the lowest loss of viability were those of 4% (w/v) pectin, 3% (w/v) sodium alginate coated with chitosan and a mixture of 2% (w/v) sodium alginate and 2% (w/v) pectin, respectively. Loss of viability of immobilized L. plantarum in 3% alginate coated with chitosan in yogurt was of 0.55 log cycles during 38 days of storage. The results of this study suggest the efficiency of immobilization techniques to increase the survival of lactobacilli in yogurt under refrigerated storage.     

Corrosion of Ceramics in Aqueous Hydrofluoric Acid

A variety of commercially available ceramic-based oxides, carbides, nitrides, and borides were evaluated for chemical attack in an azeotropic aqueous hydrofluoric acid (HF) test protocol at 90°C. Weight change measurements and microstructure analysis showed that HF corrosion in polycrystalline ceramics generally occurred at grain boundaries by the dissolution of grain boundary phases although the bulk single crystal may inherently resist attack. Virtually all commercially prepared polycrystalline oxide ceramics (i.e., Al₂O₃, TiO₂, ZrO₂) and nonoxide ceramics (i.e., Si₃N₄, AlN, BN) were extensively corroded while polycrystalline pure carbides (i.e., SiC, TiC, B₄C, WC) resisted corrosion. Equilibrium thermodynamic calculations show that these materials are soluble in HF; however, the kinetics of dissolution are slow enough in some cases to permit useful engineering lifetimes.     

Value proposition of IoT-based products and services: a framework proposal

Electronic Markets - The IoT can help firms to innovate and to address new business opportunities. However, many companies face difficulties in developing products and services based on the IoT...