Does chronic prenatal methadone exposure affect beta-receptor subtypes in placental, fetal and maternal brain homogenates?

Computer competition analysis of 3H-DHA (3H-dihydroalprenolol, a nonselective beta-adrenergic radioligand) binding in the presence of unlabeled metoprolol (a beta 1-selective antagonist) indicates the existence of both beta 1- and beta 2-adrenergic receptor subtypes in the rat placenta and confirms previous reports that both beta-adrenoceptors are present in adult rat cortex. In the fetal brain (20th day of gestation), however, only beta 1-receptors were detected. Pregnant rats were chronically exposed to methadone from day 7 to day 20 of gestation via implanted osmotic minipumps (6.3-9.0 mg/kg/day). This treatment schedule did not induce a change in the affinity and density of either beta-receptor subtype in the placental, fetal and maternal brain homogenates. The results are discussed in terms of the reported monoaminergic and opiate receptor functional interactions.     

The effect of optical design on micromanipulator spot size using CO2 laser irradiation

Objective: The study goal was to compare the laser spot size created using reflective and refractive micromanipulators with a CO₂ laser and to determine the sensitivity of spot size to laser power. Study Design and Setting: A CO₂ laser and operating microscope (400-mm focal length) was coupled to either a reflective (Cassegrain-like) or refractive micromanipulator. Laser spot size was determined by measuring the region of ablation created by laser irradiation of wood (dry tongue depressors), exposed photographic film, and agar gel using optical micrometry. Laser power varied from 0.5 to 20 W with pulse durations of 0.1 and 0.5 second. Results: The reflective micromanipulator demonstrated overall smaller spot sizes for a given laser power and lower incremental change in spot size with increasing power. The reflective design demonstrated less sensitivity to increases in laser power. Conclusions: Micromanipulator optical design can result in significant differences in laser spot size. The reflective device used in this study demonstrated less sensitivity to increasing laser power. (Otolaryngol Head Neck Surg 2002;126:593-597.)     

Extension to the ultrasonic study of supra- and subphrenic spaces of plate-shaped probes initially destined for intracavitary sonography. Research on thoraco-abdominal fluid collections in non-mobilizable patients

The authors describe an original application of real time transducers--initially intended for intracavitary sonography--in thoraco-abdominal scanning. The stic-form probe can be easily slipped under the patient. It is then possible to realize a scan with an upward beam. In the postero-anterior scan, the patient is placed in a supine position. He is motionless. We achieve a better visualization of the liquid collections, since their accumulation is declivious. The method allows a wider sonographic window for thoraco-abdominal and diaphragmatic investigation in sonography.     

Influence on binding of third-order torque to second-order angulation

Using an earlier model, which described the critical contact angle for binding from second-order angulation alone, a more generalized model is derived that combines the effects of angulation and torque. From this vantage point, the onset of binding is evaluated for 3 scenarios: second-order angulation alone, third-order torque only, and a combination of second-order angulation and third-order torque. These scenarios are detailed by plotting the critical contact angle for binding against the torque angle as a function of 10 wire dimensions (16 x 16, 16 x 22, 17 x 17, 17 x 22, 17 x 25, 18 x 18, 18 x 22, 18 x 25, 19 x 25, and 21 x 25 mil), 4 bracket widths (70, 100, 130, and 160 mil), and 4 bracket slots (18, 20.5, 22, and 24.5 mil). From these plots, we learn that each wire base dimension (eg, an 18-mil base as found in 18 x 18-mil, 18 x 22-mil and 18 x 25-mil archwires) has a common maximum critical contact angle for binding. Moreover, each wire-slot combination has a common maximum torque angle, which is independent of bracket width. Finally, we learn that archwire-bracket combinations that use a metric 0.5-mm slot might have some advantages with regard to torquing--given the current philosophy that light, continuous forces are more favorable.     

Distale Humerusfrakturen

Distal humeral fractures are problematic both in children and in adults. While in children these fractures are very common and most of them have an extraarticular location, in adults their incidence is much lower and they more often compromise the joint. Good results cannot be achieved without due consideration for the complex anatomy of the elbow joint, the quality of the bone, the concomitant soft tissue lesions and the biomechanical aspects of the injury, to allow selection of appropriate therapy and a correctly structured aftertreatment. The soft tissue injuries that are frequently involved and the high rate of intra- and postoperative complications need particular attention. This paper reviews the epidemiology, the current standards in diagnosis and therapy, the possible complications and the results that can be expected in patients with fractures of this type.