Development of a computer-aided-controlling and image analysis system for light/dark box test in mice and rats / 中国比较医学杂志

Objective To develop a computer-aided-controlling and analysis system for light/dark box in mice and rats with a high degree of automation and intelligence.Methods Video recording and image processing were applied to develop the computer-aided-controlling and image analysis system for light/dark box test in mice and rats. The artificial environment was developed. The stability and reliability of the system was validated by male rats. Results The percentage of time spent in the lit chamber in total time was above 79.40%. The data showed that the artificial environment was successful. When the threshold was set at 18 cm/s, the data showed a high correlation coefficient of movement time between the computer and manual recordings(r > 0.99). Classical indexes including transition and time spent in both the lit and dark chambers also showed a high correlation. The model group showed a significantly decrease in the transitions and time spent in the lit chamber compared with the control group, indicating a high stability and reliability of the light/dark box test. Conclusions A stable and highly intelligent computer-aided-controlling and image analysis system for light/dark box test of mice and rats has been developed,and it could be used for pathological mechanism studies of anxiolytics.

Object recognition test—a method to assess the learning and memory in mice based on their spontaneous behavior / 中国比较医学杂志

Objective To develop a multi-mode,detailed and sensitive object recognition method for learning and memory research,including novel object recognition task,object location recognition task,temporal order memory task and object context recognition task in animals based on their spontaneous behavior. Methods Two strains of mice(KM and ICR)and four patterns were used to establish the object recognition method and several relative factors,such as time of test phase,delay between test phase and familiar phase were investigated. Results It was stable and reasonable to set the time of familiar phase as 5 min,the interval between test phase and familiar phase as 10 min,and the time of test phase as 3-5 min,under the precondition of habituation for three days and selecting the appropriate object pairs. Conclusions Object recognition test including four patterns has been systematically established as a stable, reliable and normative way for the research of animal learning and memory and drug development.

The impact factors in reward conditioned reflex test of rats / 中国比较医学杂志

Objective To study the effects of different color light stimulus, duration of stimulus and day/night training on the incentive conditioned reflex of rats,and to provide a data basis for the methodology of incentive conditional reflection experiments. Methods Three experiments were included in this study. During the experiment 1, a total of 30 male 8-week-old Wistar rats were divided into three groups:red light stimulation group,yellow light stimulation group and blue light stimulation group. During the experiment 2, a total of 32 male 8-week-old Wistar rats were divided into three groups:the group I(with a light stimulation duration of 10 s), the group II(with a light stimulation duration of 30 s), and the group III(with a light stimulation duration of 60 s). During the experiment 3,a total of 16 male 8-week-old Wistar rats were randomly divided into two groups,of which the first group was trained at 9:00 a.m. every day, and the second group was trained at 21:00 every day. All the laboratory animals were given reward conditioned reflex training, and indicators such as the number of correct nose pokes,the number of incorrect nose pokes,the ratio of correct nose pokes and so on were counted and calculated. Results During the experiment 1,there was no significant difference in the numbers of correct nose pokes and incorrect nose pokes,movement distances and average speeds of the rats among the three groups. During the experiment 2,compared with the group with a light duration of 10 s,the rats in the groups with a light duration of 30 s or 60 s had a higher number of correct nose pokes(P< 0.05). Moreover,on the 13th and 14th days,the ratio of correct nose pokes of the group with a light duration of 30 s was significantly higher than that of the group with a light duration of 10 s(P< 0.001). During the experiment 3,there were no significant differences in the number of correct nose pokes and the nose poke accuracy of the rats between the two groups. Conclusions In the reward conditioned reflex test, red,yellow and blue light stimuli have similar reward prediction effect. When stimulated with the same light, the time of stimulation has an impact on the learning ability of the rats,and an appropriate extension of stimulation is beneficial to the formation of conditioned reflex in them. The day/night training has no effect on the learning and memory ability of the rats.

Review and prospect of experiment methodology on animal behavior / 中国比较医学杂志

This is a systematic review of the history and progress of animal behavior experiment methods at home and abroad, and the conception associated with animal behavior experiments. In addition, the application of animal behavior experiment methods in the field of neuropsychology and military medicine is also reviewed, providing a reference for the scientific research based on animal behavior experiments.

Comparison of the cognitive function in rats at different brain developmental stages / 中国实验动物学报

Objective To investigate the relationship between different brain developmental stages and changes of cognitive function in rats. Methods 1-month, 2-month and 8-month-old rats were selected to imitate the juvenile, adolescent and adulthood, respectively, and their behavioral functions were compared. The reward operant conditioning and Morris water maze task were used to investigate the differences in exploration interest, executive and recognition ability, spatial learning and memory of the rats at different ages. Results In the reward operant conditioning and Morris water maze task, there was no significant difference in the cognitive function between 1-month and 2-month-old rats. In the reward conditioning phase, the nose pokes numbers of 8-month-old rats were significantly decreased compared with the 1-month-old rats (P＜ 0. 01). There was no significant difference in nose pokes accuracy. During the operant conditioning phase, the lever press numbers and accuracy of 8-month-old rats were significantly decreased ( P ＜ 0. 05 or P ＜ 0. 01) and the press latency was longer (P ＜ 0. 05). At the phase of visual identification, the press and reward numbers, and the visual identification index were significantly decreased ( P ＜ 0. 05 or P ＜ 0. 01). In the Morris water maze test, compared with the 1-month-old rats, the total swimming distance and escape latency of the 8-month-old rats were significantly increased (P＜ 0. 05), as well as average swimming speed ( P ＜ 0. 05 or P ＜ 0. 01) in spatial learning phage. In spatial memory phage, the swimming distance and time spent in the target quadrant were obviously decreased (P＜ 0. 01). Conclusions The cognitive functions of rats at different brain developmental stages are different. The juvenile and adolescent rats have similar cognitive functions, but 8-month-old adult rats appear decline in the exploration interest, executive and recognition ability, and spatial learning and memory function.

Comparison of the Prognostic Utility of the Diverse Molecular Data among lncRNA, DNA Methylation, microRNA, and mRNA across Five Human Cancers.

INTRODUCTION: Advances in high-throughput technologies have generated diverse informative molecular markers for cancer outcome prediction. Long non-coding RNA (lncRNA) and DNA methylation as new classes of promising markers are emerging as key molecules in human cancers; however, the prognostic utility of such diverse molecular data remains to be explored. MATERIALS AND METHODS: We proposed a computational pipeline (IDFO) to predict patient survival by identifying prognosis-related biomarkers using multi-type molecular data (mRNA, microRNA, DNA methylation, and lncRNA) from 3198 samples of five cancer types. We assessed the predictive performance of both single molecular data and integrated multi-type molecular data in patient survival stratification, and compared their relative importance in each type of cancer, respectively. Survival analysis using multivariate Cox regression was performed to investigate the impact of the IDFO-identified markers and traditional variables on clinical outcome. RESULTS: Using the IDFO approach, we obtained good predictive performance of the molecular datasets (bootstrap accuracy: 0.71-0.97) in five cancer types. Impressively, lncRNA was identified as the best prognostic predictor in the validated cohorts of four cancer types, followed by DNA methylation, mRNA, and then microRNA. We found the incorporating of multi-type molecular data showed similar predictive power to single-type molecular data, but with the exception of the lncRNA + DNA methylation combinations in two cancers. Survival analysis of proportional hazard models confirmed a high robustness for lncRNA and DNA methylation as prognosis factors independent of traditional clinical variables. CONCLUSION: Our study provides insight into systematically understanding the prognostic performance of diverse molecular data in both single and aggregate patterns, which may have specific reference to subsequent related studies.

The different characteristics of spontaneous activity in simulated weightlessness in rats / 中国比较医学杂志

Objective To observe the different characteristics of spontaneous activitiy after simulated weightlessness 21 days in rats , aimed to provide a evaluation method for space weightlessness induced function change in human beings and to provide a reference for researches on the astronauts protective measures .Methods 30 Wistar male rats were randomly divided into three groups , the control group , the sham tail-suspended hindlimb unloading group ( the sham group ) , the tail-suspended hindlimb unloading group ( the suspending group ) , ten animals in each group .All animals were placed in the simulated space flight environmental equipment which has a real -time monitor system for 21 days.During the 21 days, the intake of water , food and the body weight were measured every week .Meanwhile, five independent activity data were collect every day , for example, morning(8:00am~12:00am), afternoon(2:00pm~6:00pm), daytime(8:00am~8:00pm),night(8:00pm~8:00am),and whole day (8:00am ~8:00am).Results The spontaneous activity of normal rats in the control group between morning and afternoon had no significant difference , but it is significantly between night and daytime .The movement time and distance in night are 2 -3 times than that of the daytime.After 10 days of tail suspending , the circadian rhythm was disordered , and the spontaneous activity in day and night become more similar in rats of the suspending group .Because of the individual difference , the spontaneous activity is not stable at the first 10 days in rats of the sham group , but after 10 days, it become close to the control group .Conclusion Rat is nocturnal animal and sleeps in the daytime , the spontaneous activity in night is 2 -3 times as compared with the daytime.The sham tail-suspended hindlimb unloading 21 days can not influence the circadian rhythm in rats .Tail suspending 21 days will caused to the disappearance in the circadian rhythm in rats .

Gender difference of pulse wave velocity / 国际生物医学工程杂志

Pulse wave velocity (PWV) is one of typical indicators to evaluate arterial stiffness.About the gender difference of pulse wave velocity,some controversies exist.In this paper,several factors affecting the differences such as height,aging,sex steroids,which affect the arterial structure and function and bring the gender difference,are reviewed relatively in detail.In addition,several aspects including measurement accuracy,analyzing method and the characteristics of sample population,which may induce the difference of PWV results,are also briefly reviewed.Meanwhile,some existing controversies are indicated objectively to further possible research interests in this field.

Effects of Simulated Environment of Spaceflight on Phonetic Features of Speech / 航天医学与医学工程

Objective To study changes of phonetic features of mandarin speech when the talker is in stressed environment of spaceflight.Methods The mandarin speech database was established from volunteers speech in 72 h psychological isolation & sleep deprivation experiment,60 d head-down-tilt bed-rest experiment and 60 d sealed module experiment.The phonetic features were fundamental frequency,syllable duration and short-term energy of speech.Results In above three kinds of stressed environments,the changes of fundamental frequency were correlated with appearance of annoyance emotion of volunteers.But changes of syllable duration and short-term energy were related to different time points during experiments.Conclusion According to the findings,acoustic changes of speech under simulated environment of spaceflight may provide important reference to the study of emotional speech recognition in spaceflight for the future.

Study on Technology of Space Flight Training Simulator and Its Engineering Implementation / 航天医学与医学工程

Space flight training simulator is one of the important equipments for astronaut training on ground.Based on general international classification criteria,technology principle and engineering implementation of simulators developed in our country were introduced.The key technology of developing simulators was discussed.The prospect of development for future studies and applications were looked forward to.