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1.
Dent Mater ; 27(10): 1011-6, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21802131

ABSTRACT

OBJECTIVE: Test the hypothesis that glass-bonding of free-form veneer and core ceramic layers can produce robust interfaces, chemically durable and esthetic in appearance and, above all, resistant to delamination. METHODS: Layers of independently produced porcelains (NobelRondo™ Press porcelain, Nobel BioCare AB and Sagkura Interaction porcelain, Elephant Dental) and matching alumina or zirconia core ceramics (Procera alumina, Nobel BioCare AB, BioZyram yttria stabilized tetragonal zirconia polycrystal, Cyrtina Dental) were joined with designed glasses, tailored to match thermal expansion coefficients of the components and free of toxic elements. Scanning electron microprobe analysis was used to characterize the chemistry of the joined interfaces, specifically to confirm interdiffusion of ions. Vickers indentations were used to drive controlled corner cracks into the glass interlayers to evaluate the toughness of the interfaces. RESULTS: The glass-bonded interfaces were found to have robust integrity relative to interfaces fused without glass, or those fused with a resin-based adhesive. SIGNIFICANCE: The structural integrity of the interfaces between porcelain veneers and alumina or zirconia cores is a critical factor in the longevity of all-ceramic dental crowns and fixed dental prostheses.


Subject(s)
Dental Bonding , Dental Porcelain , Dental Veneers , Glass , Aluminum Oxide , Crowns , Dental Stress Analysis , Elastic Modulus , Glass/chemistry , Hardness , Materials Testing , Vitrification , Yttrium , Zirconium
2.
Am J Transplant ; 10(9): 2142-7, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20738267

ABSTRACT

A male infant was diagnosed with atypical hemolytic uremic syndrome (aHUS) at the age of 5.5 months. Sequencing of the gene (CFH) encoding complement factor H revealed a heterozygous mutation (c.3644G>A, p.Arg1215Gln). Despite maintenance plasmapheresis he developed recurrent episodes of aHUS and vascular access complications while maintaining stable renal function. At the age of 5 years he received an isolated split liver graft following a previously established protocol using pretransplant plasma exchange (PE) and intratransplant plasma infusion. Graft function, renal function and disease remission are preserved 2 years after transplantation. Preemptive liver transplantation prior to the development of end stage renal disease is a valuable option in the management of aHUS associated with CFH mutations.


Subject(s)
Complement Factor H/genetics , Hemolytic-Uremic Syndrome/genetics , Hemolytic-Uremic Syndrome/surgery , Liver Transplantation , Mutation , Caliciviridae Infections/etiology , Gastroenteritis/virology , Hemolytic-Uremic Syndrome/physiopathology , Herpesvirus 4, Human , Heterozygote , Humans , Infant, Newborn , Kidney/physiopathology , Liver Transplantation/adverse effects , Male , Norovirus , Postoperative Complications , Risk Assessment , Secondary Prevention , Viremia/etiology
3.
Am J Bot ; 87(6): 811-8, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10860911

ABSTRACT

Giant cutgrass [Zizaniopsis miliacea], a tall emergent grass native to the southeastern United States, was studied in two Florida lakes. In Lake Seminole (15 176 ha) giant cutgrass forms large expanding stands, but in Lake Alice (9 ha) it is confined to a stable narrow fringe. By monitoring individual plants in Lake Seminole, it was found that an average decumbent flowering stem produced three flowers and ten nodes, 80% of which became rooted in the substrate. Such flowering stem development could potentially result in stand expansion of 2.2-2.7 m/yr, depending upon water levels and rates of node rooting. Once flowering stems became decumbent in Lake Alice, they typically broke, producing no more than two flowers with four nodes in a growing season. While still attached to the parent plant, few of these nodes were able to become rooted in the substrate, limiting the rate of stand expansion in Lake Alice. Sections of flowering stems bearing axillary shoots that were detached from the parent plant and free-floating could become rooted on reaching shallow water and produce robust, new, flowering plants. This interesting mode of population dispersal and spread has important implications for the distribution and management of giant cutgrass.

4.
Appl Biochem Biotechnol ; 30(1): 83-98, 1991 Jul.
Article in English | MEDLINE | ID: mdl-1952925

ABSTRACT

Four different nonporous particulate materials, nylon, polystyrene, soda-lime silicate glass, and fused silica glass, have been evaluated for their appropriateness as immobilization supports for immunoglobulins. A method of protein quantitation that is usually applied to solutions, the bicinchoninic acid (BCA) assay, was used successfully to directly measure ng amounts of protein immobilized on the supports. Two proteins, a monoclonal antibody to theophylline and the biotin binding protein avidin, were studied. Radioactive theophylline and radioactive biotin were used to measure the activity of the immobilized protein. Ligand binding capacity per mm2 of support was measured as a function of amount of protein immobilized. By measuring both the amount of protein immobilized and its ligand binding capacity, we have determined that antitheophylline antibody adsorbed on polystyrene balls loses almost 90% of its binding activity after 65 h, although little protein is lost from the balls over this time. Avidin retains nearly full activity for biotin on polystyrene. The binding activity of biotinyl-antibody conjugate immobilized on avidin-adsorbed polystyrene is stable, even when stored for over 22 wk. Antibody covalently immobilized on soda-lime silicate glass beads retains its binding activity over long-term storage, although only 0.1 mol of 3H-theophylline bind per mol of immobilized antibody. Using fused silica glass particles as the solid support, the same antibody binds approx 0.6 mol of ligand per mol of immobilized antibody protein. The structural "softness" of the immunoglobulin requires that interaction with the surface be prevented in order to maintain activity.


Subject(s)
Glass/chemistry , Nylons/chemistry , Polystyrenes/chemistry , Proteins/chemistry , Adsorption , Avidin/chemistry , Immunoglobulins/chemistry , Theophylline/immunology
6.
Fortschr Med ; 107(18): 63-4, 67-8, 1989 Jun 20.
Article in German | MEDLINE | ID: mdl-2526787

ABSTRACT

Low back pain for which operative therapy is not indicated, can prove resistant to treatment even with the aggressive application of conservative measures and the use of suitable drugs. Here, local anesthesia can often have a decisive influence on pain. On account of possible complications, particular consideration must be given to pharmacological aspects. Moreover, certain minimum demands must be met by the equipment and personnel staffing of a pain clinic, and also the possibilities for monitoring the patient. Within the framework of an interdisciplinary pain clinic, the various blockade techniques employed for therapeutic local anesthesia provide suitable possibilities for combatting this type of pain.


Subject(s)
Analgesia, Epidural , Anesthesia, Local , Back Pain/therapy , Anesthetics, Local/adverse effects , Humans , Risk Factors
8.
Fortschr Med ; 107(6): 147-9, 1989 Feb 28.
Article in German | MEDLINE | ID: mdl-2703203

ABSTRACT

On the basis of our experience with more than 600 reconstructed capsular ligament injuries of the knee joint, we conclude that conservative functional treatment should be preserved for patients with capsular ligament lesions with no loss of stability. On an individual basis, it must be decided whether, in the event of a more or less large degree of instability presenting, conservative mobilising treatment (patients older than 45 years), or surgical reconstructive treatment should be provided. Surgical procedures aim at achieving anatomical reconstruction, which is only approximately possible with secondary reconstruction in the presence of chronic instability. For the reconstruction of the anterior cruciate ligament, the use of the semitendinosus tendon for reinforcement with possible reattachment of the cruciate ligament can be recommended. Otherwise, the free patellar ligament transplant, as far as possible with additional synovialisation--which permits better revitalisation of the ligament--should be employed.


Subject(s)
Knee Injuries/surgery , Ligaments, Articular/injuries , Follow-Up Studies , Humans , Joint Instability/surgery , Rupture
9.
Fortschr Med ; 107(6): 144-6, 1989 Feb 28.
Article in German | MEDLINE | ID: mdl-2649428

ABSTRACT

Despite the enormous developments in imaging procedures, the patient's history and clinical examination remain the basis for the diagnosis of fresh injuries to the knee. The description of the mechanisms of the accident as revealed by the case history already provides important clues. The clinical examination must cover all the anatomical detection of lesions of individual parts of the capsular ligaments. With an appropriate knowledge of anatomy, and adequate experience in performing the examination, the general physician (with no specialized orthopedic knowledge) can obtain a good idea of the nature and severity of the injury.


Subject(s)
Athletic Injuries/diagnosis , Knee Injuries/diagnosis , Ligaments, Articular/injuries , Arthroscopy , Humans
15.
Rofo ; 147(2): 191-5, 1987 Aug.
Article in German | MEDLINE | ID: mdl-2819977

ABSTRACT

The osseous manifestations of osteochondrosis dissecans are well demonstrated by conventional and computerised tomography. Beyond that, magnetic resonance imaging (MRI) is effective in evaluating the vitality and loosening of an osseous dissecate. Subchondral cavities and cartilaginous defects are detected with high accuracy. Further, MRI seems to be a useful method in childhood to differentiate a variant irregularity of the osseous articular surface from definite osteochondrosis dissecans.


Subject(s)
Magnetic Resonance Spectroscopy , Osteochondritis Dissecans/diagnosis , Osteochondritis/diagnosis , Adolescent , Adult , Arthroscopy , Child , Humans , Joint Loose Bodies/diagnosis , Joint Loose Bodies/etiology , Middle Aged , Osteochondritis Dissecans/complications , Osteosclerosis/diagnosis
16.
Z Orthop Ihre Grenzgeb ; 124(6): 755-8, 1986.
Article in German | MEDLINE | ID: mdl-3564643

ABSTRACT

With magnetic resonance imaging it is possible to demonstrate the cruciate ligaments of the knee reproducibly without the need for invasive measures. Prerequisites for this are high-resolution coil systems and a stratum thickness of 5 mm or less. Examination of 29 patients and volunteers showed that normal cruciate ligaments can be delineated as homogeneous zones of low signal intensity and high contrast from the surrounding fatty tissue, while in cases of injury to the cruciate ligaments an interruption of the ligament structure, inability to detect them in anatomic position, or an intermediate signal is observed. In 13 cases operated on, with 12 injuries of the cruciate ligaments, the MR findings corresponded to findings at surgery. In 6 patients who had previously had cruciate ligament plasties there correlation with clinical findings was only partial.


Subject(s)
Knee Injuries/pathology , Knee Joint/pathology , Ligaments, Articular/injuries , Magnetic Resonance Spectroscopy , Adolescent , Adult , Female , Humans , Knee Injuries/surgery , Ligaments, Articular/pathology , Ligaments, Articular/surgery , Male , Middle Aged , Postoperative Complications/pathology
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