The use of multi-detector row computed tomography (MDCT) as an alternative to specimen preparation for anatomical instruction

The purpose of the study reported here was to establish a method of teaching veterinary anatomy, including radiologic anatomy, for clinical practice using computer-aided diagnosis (CAD). Two clinically healthy dogs and three cats were scanned using multi-detector row computed tomography (MDCT). Images were made by means of imaging processing software. At the workstation, by observing the transverse, dorsal-plane, or sagittal sections and three-dimensional (3D) images simultaneously, it is much easier to understand the 3D anatomical structure. With this educational support system, anatomical figures can be explained using living animals instead of specimens. In addition, clinical representative examples can be used to show anatomical disorders to students. Veterinary students (N = 62) who filled out a questionnaire evaluating how the method aided their understanding of both experimental study and clinical examples gave it a score of 88.2 +/- 20.6 (Mean +/- SD) on a visual analog scale. This system can enhance veterinary students' understanding and interest in anatomy and can enable us to offer them a quality veterinary medical education. We concluded that CAD is a useful new option not only for clinical service but also for veterinary education.     

Absorption, tissue distribution, excretion, and metabolism of clothianidin in rats

Absorption, distribution, excretion, and metabolism of clothianidin [(E)-1-(2-chloro-1,3-thiazol-5-ylmethyl)-3-methyl-2-nitroguanidine] were investigated after a single oral administration of [nitroimino-(14)C]- or [thiazolyl-2-(14)C]clothianidin to male and female rats at a dose of 5 mg/kg of body weight (bw) (low dose) or 250 mg/kg of bw (high dose). The maximum concentration of carbon-14 in blood occurred 2 h after administration of the low oral dose for both labeled clothianidins, and then the concentration of carbon-14 in blood decreased with a half-life of 2.9-4.0 h. The orally administered carbon-14 was rapidly and extensively distributed to all tissues and organs within 2 h after administration, especially to the kidney and liver, but was rapidly and almost completely eliminated from all tissues and organs with no evidence of accumulation. The orally administered carbon-14 was almost completely excreted into urine and feces within 2 days after administration, and approximately 90% of the administered dose was excreted via urine. The major compound in excreta was clothianidin, accounting for >60% of the administered dose. The major metabolic reactions of clothianidin in rats were oxidative demethylation to form N-(2-chlorothiazol-5-ylmethyl)-N'-nitroguanidine and the cleavage of the carbon-nitrogen bond between the thiazolylmethyl moiety and the nitroguanidine moiety. The part of the molecule containing the nitroguanidine moiety was transformed mainly to N-methyl-N'-nitroguanidine, whereas the thiazol moiety was further metabolized to 2-(methylthio)thiazole-5-carboxylic acid. With the exception of the transiently delayed excretion of carbon-14 at the high-dose level, the rates of biokinetics, excretion, distribution, and metabolism of clothianidin were not markedly influenced by dose level and sex.