ABSTRACT
In this study, a rat morphine drug discrimination model with a fixed ratio (FR) of 10 (FR10) was established using different methods to explore which methods can shorten the modeling time and test the dose-response relationship and median effective dose (ED50) value. Animal welfare and experimental procedures are in accordance with the provision of the Animal Ethics Committee of Shanghai InnoStar Bio-tech Co., Ltd. Forty rats were initially shaped to press lever under a fixed-ratio schedule of food reinforcement. The animals that were successfully trained under a FR10 schedule of food reinforcement were divided into two groups, namely the single-lever + double-lever training group 1 and the double-lever training group 2. In each group, rats were trained to discriminate morphine at 5.6 mg·kg-1 from saline by the intraperitoneal route. After training, different doses of morphine were used to substitute for training dose of morphine, the dose-response curve for morphine were identified in rats, and the ED50 value was calculated. The results showed that, in food training phase: 34 rats successfully entered the discrimination training during food training; in discrimination training phase: 14 animals in group 1 met the discrimination training standard for the first time, which took about (40.71 ± 2.93) days, and there were 13 animals in group 2 that met the discrimination training criteria for the first time, and it took about (51.15 ± 2.55) days. It can be seen that the method of single-lever + double-lever training is better than single-lever training, and the difference is significant compared with group 1 (P ˂ 0.05); in generalization test phase: there are 17 rats completed morphine generalization test, and the percentages of morphine-lever responses produced by the generalization test of different doses of morphine (0, 0.1, 0.5, 1, 3, 5.6, and 10 mg·kg-1) were (9.56 ± 3.13) %, (9.01 ± 5.83) %, (13.82 ± 7.95) %, (29.04 ± 10.13) %, (41.70 ± 10.65) %, (85.36 ± 7.16) %, (94.56 ± 2.76) %, respectively. The results showed that the discriminative stimulative effect induced by morphine dose between 0-10 mg·kg-1 increased in a dose-dependent manner, producing a good dose-response curve, and the ED50 value of morphine was 4.74 mg·kg-1 by linear fitting. The above results showed that, the FR10 morphine drug discrimination model has been successfully established using different methods; the single-lever + double-lever training method is better than the single-lever training, and can relatively shorten the discrimination training cycle.
ABSTRACT
With the progress and development of the DNA test and imaging technique, and the evolution of evidence rule which bring the discussions about whether the individual identification using imaging data is outdated, and other disputes such as whether radiologic evidence could be suitable for contemporary evidence and be used to solve the posture difference of imaging test. This article summaries the domestic and foreign researches of individual identification using imaging data in the past 20 years and reviews the problems above.
Subject(s)
Humans , DNA/analysis , Forensic Genetics/standardsABSTRACT
As an important component of judicial expertise, forensic science is broad and highly specialized. With development of network technology, increasement of information resources, and improvement of people's legal consciousness, forensic scientists encounter many new problems, and have been required to meet higher evidentiary standards in litigation. In view of this, evidence-based concept should be established in forensic medicine. We should find the most suitable method in forensic science field and other related area to solve specific problems in the evidence-based mode. Evidence-based practice can solve the problems in legal medical field, and it will play a great role in promoting the progress and development of forensic science. This article reviews the basic theory of evidence-based medicine and its effect, way, method, and evaluation in the forensic medicine in order to discuss the application value of forensic evidence-based medicine in computer communication networks.