Tauchunfälle

Notfall + Rettungsmedizin - Tauchunfälle sind vergleichsweise selten und stellen (Erst‑)Helfer vor besondere Herausforderungen. Sie müssen schnell und kompetent behandelt werden, da...     

A novel assay for factor XIII based on cross-linking of synthetic peptides: analysis of different substrates.

A novel assay for factor XIII is described that utilizes exclusively small synthetic peptides as substrates for the cross-linking reaction catalyzed by activated factor XIII (FXIIIa). The acyl donor substrate (selection peptide) is immobilized on a microplate via biotin while the acyl acceptor substrate (detection peptide) is labeled with the fluorochrome Oregon green to allow sensitive detection without the need for secondary enzyme systems for signal amplification. Starting with an amino acid sequence from the fibrin gamma-chain (GQQHHLGGAKQAGDV) as a prototype peptide, the influence of amino acid exchanges were investigated with respect to their impact on the FXIIIa-catalyzed reaction. It was found that FXIIIa readily accepts a broad range of substrate peptides, with a proline neighboring the essential lysine having the most detrimental effect. The assay appears to be valuable for the molecular characterization of factor XIII and may be used for a deeper investigation into the substrate requirements of this final enzyme of wound repair, and eventually also for the characterization of other transglutaminases.     

Komplikationen der Nagelosteosynthese am proximalen Humerus

In a prospective outcome study, 76 of 116 patients were examined 1 year after reduction and internal fixation of a dislocated humeral head fracture with an antegrade straight intramedullary nailing system using angular and sliding stable interlocking screws. Of these patients, 77% had three- or four-segment fractures according to the Neer classification. The mean absolute Constant-Murley score 1 year after trauma was 70.0±19.7 points. During the observation period, 51 complications occurred in 44 of 76 patients; of these 44 patients, only 27 required therapeutic interventions. The highest frequency of complications was apparent in those with Neer IV fractures (73.7%), while those with Neer III and Neer IV/III fractures had complication rates of 50% and 52.5%, respectively. Patients without complications showed good or excellent functional results, ranging from 78% to 96% (relative Constant-Murley score of the contralateral noninjured side). In patients with complications, the relative Constant-Murley score ranged from 51% to 65%. Despite the high complication rate, the antegrade angular and sliding stable interlocking nail can be considered effective for treating dislocated humeral head fractures. Modifications of the surgical technique for stabilizing the tubercles (additional suture cerclage fixation of fragmented tubercles) and a polyetheretherketone (PEEK) insert in the proximal segment of the nail to prevent the fixation screws from backing out can substantially decrease some of the most frequent complications.     

Microbiologic findings in protracted and chronic enterocolitis]

Novel diagnostic methods (immunoblotting, immunofluorescence test) have been proved to be very sensitive and specific for detecting enteropathogenic bacilli. 28 patients with chronic enterocolitis were investigated. In 50% (14/28) of these patients Yersinia enterocolitica could be visualized in biopsies by immunofluorescence. The serum of 8 patients also contained IgA-antibodies against plasmid encoded released proteins of Y. enterocolitica. This paper reports evidence for persistence of Yersinia bacilli in a group of patients with chronic enterocolitis. Further studies must show, if these results may have therapeutic implications.     

In vitro and clinical feasibility study with an over-the-wire delivery system for pulsed dye laser angioplasty.

The suitability of a pulsed dye laser (504 nm) in experimental and clinical angioplasty was investigated. In an experimental study, the ablation thresholds were 3 J/cm2 +/- 8 (mean +/- standard deviation) for fibrofatty plaque and 25 J/cm2 for calcified tissues under saline. At a radiant exposure of 10 J/cm2 the etch rates were 1.7 microns per pulse +/- 0.3 for media, 2.8 microns/pulse +/- 0.4 for normal intima, and 3.9 microns/pulse +/- 1.1 for fibrofatty plaque (P less than .05). Pressure wave effects with a separation of tissue layers were predominantly localized at the internal elastic lamina. Thermal injury with vacuolations extended 15 microns +/- 6 into adjacent tissue. For clinical study, laser-assisted balloon angioplasty was performed in 10 patients (64 years +/- 14) with occlusions of peripheral arteries using a 9-F multifiber ring catheter. Lesion length ranged from 2 to 12 cm (mean, 7 cm). Laser angioplasty with an 80 mJ/pulse decreased the mean stenosis from 100% to 58% +/- 12% (P less than .005). The ankle-brachial index rose from a median of 0.48 to 0.88 (P less than .001). In 33% of patients, there were subintimal dissections after laser angioplasty. After a mean follow-up of 10.2 months, the overall clinical success was 70% with a primary patency of 78%. The over-the-wire approach with a pulsed dye laser may constitute a safe and feasible tool in laser angioplasty.     

Beauty and the eye of the beholder: social consequences and personal adjustments for facial patients

Patients' pre- and postoperative self-reports were compared with reports of non-medical observers to investigate whether improved self-esteem is a direct result of increased social acceptance in maxillo- and craniofacial patients. Twenty-two children and adolescents undergoing reconstructive surgery for a variety of facial deformities were asked to rate their physical appearance on the Hay's Scale and fill out the Piers-Harris Self-Concept Scale. Their ratings were compared with scores given by a panel of lay volunteers on random presentation of pre- and postoperative photographs of the same patients. Patients rated their appearance as noticeably improved after surgery, their self-esteem rose significantly and they reported more social adeptness and acceptance at home and school. Raters observed only relatively subtle changes. Apparently, quality of life improved for the postsurgical facial patient because of increased self-esteem and confidence, which free him to overcome social barriers.