The influence of direct electric stimulation on nerve regeneration was studied in a model of crush injury of the sciatic nerve of rats. Forty-three rats were used and distributed in four groups according to the procedure: (1) intact nerve, inactive circuit; (2) crush injury, inactive circuit; (3) intact nerve, active circuit; (4) crush injury, active circuit. The low intensity continuous current circuit (1 mA) was implanted in the lumbar region, the anode being fixed to the muscles proximally and the cathode below the nerve distally to the lesion site. The Sciatic Functional Index (SFI) was evaluated at weekly intervals for 3 weeks, the sciatic nerve being resected on the 21st day for histologic and morphometric studies. The SFI progressively improved and the average fiber nerve density recovered to a nearly normal value in Group 2 and increased in Group 4 compared with the control groups (1 and 3), but this was accompanied by a decreased average fiber nerve diameter. Both number and diameter of inter and intra-fascicular blood vessels increased in the stimulated nerves. We conclude that low intensity direct electric stimulation enhances nerve regeneration following a controlled nerve crush injury and increases blood supply by increasing number and diameter of vasa nervorum. #

An experimental study on the correlation between functional and morphologic recovery of crushed sciatic nerves was carried out in rats. The sciatic nerve of 33 rats, divided into three groups, was submitted to controlled crushing injury on a 5-mm long segment, in a universal testing machine for 10 min with three different loads (100, 500, and 15,000 g, respectively). Functional recovery was evaluated, using a modified sciatic functional index (SFI) at weekly intervals up to the 60th postoperative day, at which time, the animals were sacrificed for histologic and morphometric studies of the nerves. Results were compared with those of normal untouched nerves and nerves submitted to segmentary resection without repair. Initial loss of function was observed in all animals with crush injury, but recovery to a nearly normal SFI occurred after progressively longer intervals (25, 39, and 53 days), as a function of load. Nerve-fiber density was increased in the groups submitted to lower loads, but statistically significantly decreased in the animals submitted to the 15,000-g crush. The authors conclude that the SFI is directly correlated with nerve-fiber density and, therefore, is an adequate tool for evaluating sciatic functional deficiency in the rat.

Peripheral nerves are structures that, when damaged, can result in significant motor and sensory disabilities. Several studies have used therapeutic resources with the aim of promoting early nerve regeneration, such as the use of low-power laser. However, this laser therapy does not represent a consensus regarding the methodology, thus yielding controversial conclusions. The objective of our study was to investigate, by functional evaluation, the comparative effects of low-power laser (660 nm and 830 nm) on sciatic nerve regeneration following crushing injuries. Twenty-seven Wistar rats subjected to sciatic nerve injury were divided into three groups: group sham, consisting of rats undergoing simulated irradiation; a group consisting of rats subjected to gallium-aluminum-arsenide (GaAlAs) laser at 660 nm (10 J/cm(2), 30 mW and 0.06 cm(2) beam), and another one consisting of rats subjected to GaAlAs laser at 830 nm (10 J/cm(2), 30 mW and 0.116 cm(2)). Laser was applied to the lesion for 21 days. A sciatic functional index (SFI) was used for functional evaluation prior to surgery and on days 7, 14, and 21 after surgery. Differences in SFI were found between group 660 nm and the other ones at the 14th day. One can observe that laser application at 660 nm with the parameters and methods utilised was effective in promoting early functional recovery, as indicated by the SFI, over the period evaluated.

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Although mental disorders are frequent among dermatological patients, little is known about their recognition by dermatologists. This study aimed to assess dermatologists' ability to recognize depressive and anxiety disorders. All adult outpatients who visited four dermatologists on predetermined days (n=317) completed the 12-item General Health Questionnaire (GHQ-12) and the section on depressive and anxiety disorders of the Patient Health Questionnaire (PHQ). Dermatologists, masked to GHQ-12 and PHQ scores, rated patients' mental health status. The analysis was performed on 277 patients (87%) with complete data. With the PHQ as criterion standard, the dermatologists' assessment sensitivity was 33%, while specificity was 76%. In most cases of disagreement between the dermatologists and the PHQ, the GHQ-12 corroborated the PHQ classification. Anxiety disorders tended to be recognized better than depressive disorders. Among patients with a PHQ diagnosis, male gender tended to be associated with misclassification by dermatologists. Although limitations inherent in self-report psychiatric assessment should be considered, this study suggests that mental disorders often go unrecognized in dermatological patients. This issue might be addressed by implementing specific training programmes, using validated screening questionnaires for depression and anxiety, and developing rational consultation-liaison services.

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Ultrasonometry seems to have a future for the evaluation of fracture healing. Ultrasound propagation velocity (USPV) significantly decreases at the same time that bone diameter decreases as healing takes place, thus approaching normal values. In this investigation, both USPV and broadband ultrasound attenuation (BUA) were measured using a model of a transverse mid-diaphyseal osteotomy of sheep tibiae. Twenty-one sheep were operated and divided into three groups of seven, according to the follow-up period of 30, 60, and 90 days, respectively. The progress of healing of the osteotomy was checked with monthly conventional radiographs. The animals were killed at the end of the period of observation of each group, both operated-upon and intact tibiae being resected and submitted to the measurement of underwater transverse and direct contact transverse and longitudinal USPV and BUA at the osteotomy site. The intact left tibia of the 21 animals was used for control, being examined on a symmetrical diaphyseal segment. USPV increased while BUA decreased with the progression of healing, with significant differences between the operated and untouched tibiae and between the periods of observation, for most of the comparisons. There was a strong negative correlation between USPV and BUA. Both USPV and BUA directly reflect and can help predict the healing of fractures, but USPV alone can be used as a fundamental parameter. Ultrasonometry may be of use in clinical application to humans provided adequate adaptations can be developed. ß