Albumin solder covalently bound to a polymer membrane: New approach to improve binding strength in laser tissue soldering in-vitro.

Laser tissue soldering (LTS) based on indocyanine green (ICG)-mediated heat-denaturation of proteins might be a promising alternative technique for micro-suturing, but up to now the problem of too weak shear strength of the solder welds in comparison to sutures is not solved. Earlier reports gave promising results showing that solder supported by carrier materials can enhance the cohesive strength of the liquid solder. In these studies, the solder was applied to the carriers by dip coating. Higher reliability of the connection between the solder and the carrier material is expected when the solder is bound covalently to the carrier material. In the present study a poly(ether imide) (PEI) membrane served as carrier material and ICG-supplemented albumin as solder substrate. The latter was covalently coupled to the carrier membrane under physiological conditions to prevent structural protein changes. As laser source a diode continuous-wave laser emitting at 808 nm with intensities between 250 mW and 1500 mW was utilized. The albumin functionalized carrier membrane was placed onto the tunica media of explanted pig thoracic aortae forming an overlapping area of approximately 0.5×0.5 cm2. All tests were performed in a dry state to prevent laser light absorption by water. Infrared spectroscopy, spectro-photometrical determination of the secondary and primary amine groups after acid orange II staining, contact angle measurements, and atomic force microscopy proved the successful functionalization of the PEI membrane with albumin. A laser power of 450 mW LTS could generate a membrane-blood vessel connection which was characterized by a shear strength of 0.08±0.002 MPa, corresponding to 15% of the tensile strength of the native blood vessel. Theoretically, an overlapping zone of 4.1 mm around the entire circumference of the blood vessel could have provided shear strength of the PEI membrane-blood vessel compound identical to the tensile strength of the native blood vessel. These in-vitro results confirmed the beneficial effects of solder reinforcement by carrier membranes, and suggest LTS with covalently bound solders on PEI substrates for further studies in animal models.

Detection of vaccinia virus DNA by quartz crystal microbalance.

In this study, we describe a detection system for the indirect detection of vaccinia virus by DNA analysis. The system uses quartz crystal microbalance (QCM) as the detection technique and polymerase chain reaction (PCR) for amplification. Different immobilization strategies for the capture probe on the quartz chip are studied. For the QCM detection of hybridisation, the influence of the structure and length of target DNA is analyzed. For the detection of DNA from an amplification product, an efficient denaturation procedure is developed. On the basis of these investigations, vaccinia virus DNA is detected with only a low number of amplification rounds and a short analysis time. Specificity can be clearly shown. To enhance the signal strength and to have a further proof of specificity, a gold nanoparticle-tagged enhancer sequence can be used.

Paradoxical intention and recursive anxiety.

The present study was designed to investigate a possible relationship between "recursive anxiety" and paradoxical intention. Groups of subjects were chosen from among individuals with public speaking concerns. and for whom fear of fear or recursive anxiety clearly represented an important element, or was completely absent from the clinical profile. These subjects were offered a standard in vivo treatment program for public speaking phobia with inclusion or exclusion of paradoxical intention. A 2 x 2 factorial design was employed. Those whose public speaking anxiety was complicated by recursive anxiety experienced greater improvement when paradoxical intention was included in the treatment program than when it was not employed. In contrast, individuals reporting simple public speaking phobia demonstrated greater success with a treatment program in which paradoxical intention was absent. Wegner's hypothesis of "ironic" cognitive processing was used to explain the proposed relationship between paradoxical intention and fear of fear.

Migration of a maxillofacial fixation device.

A case is reported of a Kirschner wire, used during orthognathic surgery (genioplasty), migrating to the floor of the mouth. After removal was attempted, the protruding portion of the wire was smoothed flush to the lingual mandibular border. Subsequent healing was uneventful.

Coping styles, paradox, and the cold pressor task.

The study investigated how coping style differences affected performance on the cold pressor task. Reactions of "monitors" (individuals who prefer having information about stressors) and "blunters" (individuals who avoid cues connected with stressors) were compared, using different instructional sets. The study also assessed the effectiveness of paradoxical intention compared to more traditional cognitive strategies. Monitors and blunters were identified using Miller's recently developed Behavioral Style Scale. All instructional sets improved performance in comparison to a control condition, and individuals generally did better when an instructional set supported their preferred coping style. Paradoxical intention did not show any decided advantage over other strategies. The desirability of designing stress management programs to fit individual coping style patterns is discussed.

Paradoxical intention in the treatment of agoraphobia and other anxiety disorders.

Following a description of the paradoxical intention procedure and a brief review of the general behavioral literature relevant to this technique, the authors focus on the role of paradoxical treatment programs for agoraphobic clients. The cognitive and exposure components of paradoxical intention are discussed and the procedure is compared and contrasted with other cognitive behavioral methods on one hand, and with flooding on the other. Finally, the authors provide several ideas for future research.

Comparison of three cognitive strategies in altering pain behaviors on a cold pressor task.

The efficacy of three cognitive strategies for coping with pain was examined in a cold-water pressor task in a sample of college students. Subjects were pretested and then randomly assigned to one of three treatment conditions (Paradoxical Intention, Rational Self-statement, or Self-observation) or to an expectancy control group. Following training in the respective cognitive strategies, all groups were given a posttest in the cold-water pressor to determine the effectiveness of the treatment. Pain thresholds, tolerances, and discomfort ratings were recorded for subjects in each condition. No differences were found between the Paradoxical Intention or Rational Self-statement groups and the Expectancy Control on any of the pain measures. The Self-observation treatment condition, however, had significantly higher pain tolerance scores than the Expectancy Control group. The findings were attributed to the subjects' dissociating the sensory aspects of the pain experience from the anxiety when focusing upon the coldness and wetness of the cold water.

Should fearful individuals be instructed to proceed quickly or cautiously?

Snake or cockroach phobic Ss were given opportunities to approach a live specimen. Those instructed to go "as far as they could" made significantly more progress in overcoming their fear than Ss asked to proceed cautiously. They also did better than the group especially urged to push themselves, although this difference was not significant. Implications for treatment strategies are discussed.