A Low-Cost High-Definition Video System for Microsurgical Hindlimb Replantation in Rats.

Background The surgical microscope is still essential for microsurgery, but several alternatives that show promising results are currently under development, such as endoscopes and laparoscopes with video systems; however, as yet, these have only been used for arterial anastomoses. The aim of this study was to evaluate the use of a low-cost video-assisted magnification system in replantation of the hindlimbs of rats. Methods Thirty Wistar rats were randomly divided into two matched groups according to the magnification system used: the microscope group, with hindlimb replantation performed under a microscope with an image magnification of 40× and the video group, with the procedures performed under a video system composed of a high-definition camcorder, macrolenses, a 42-in television, and a digital HDMI cable. The camera was set to 50× magnification. We analyzed weight, arterial and venous caliber, total surgery time, arterial and venous anastomosis time, patency immediately and 7 days postoperatively, the number of stitches, and survival rate. Results There were no significant differences between the groups in weight, arterial or venous caliber, or the number of stitches. Replantation under the video system took longer (p < 0.05). Patency rates were similar between groups, both immediately and 7 days postoperatively. Conclusion It is possible to perform a hindlimb replantation in rats through video system magnification, with a satisfactory success rate comparable with that for procedures performed under surgical microscopes.

An automated marine biomonitoring system for assessing water quality in real-time.

On-line behavioural monitoring systems are nowadays a common tool in ecotoxicological research. Although applied successfully to freshwater species, they are rarely used in the marine field. Here we present first results about the Marine On-line Biomonitor System (MOBS), a new automatic system for recording behavioural responses of marine and freshwater species. Low power electrical signals are modulated by the behavioural activities of the organisms and then monitored, processed and analysed in real-time. We applied this system to two marine fish species, seabream (Sparus aurata) and turbot (Scophthalmus maximus), and studied their behavioural responses at an acute hypoxic test condition (2 mg O2 l(-1)). The tests were performed for 15 min in small test chambers with isolated fish as well as in large aquaria with groups of six fish. In both cases, MOBS recorded significant alterations in their behaviour: isolated juvenile seabream increased their ventilation frequency (VF) in average by 20%, and grouped fish decreased their swimming activities by 40%. In contrast, isolated juvenile turbot responded to hypoxia with a 36% lower VF. The consequences for data interpretation based on tests for individual fish or groups of fish are discussed.