Mice learn from the predator-attack experience to accelerate flight behavior via optimizing the strategy of environment exploration.

Efficiently avoiding predators is critical for animal survival. However, little is known about how the experience of predator attack affects behaviors in predator defense. Here, we caught mice by tail to simulate a predator attack. We found that the experienced mice accelerated the flight in response to the visual threaten cue. Single predator attack didn't induce anxiety but increased the activity of innate fear or learning related nucleus. The predator attack induced acceleration of flight was partly rescued when we used drug to block protein synthesis which is critical in the learning process. The experienced mice significantly reduced the focused exploration on the floor during the environment exploration, which might facilitate the discovery of predator. These results suggest that mice could learn from the experience of predator attack to optimize their behavioral pattern to detect the predator cue immediately and response intensely, and therefore increase the probability of survival.

An iterative neural processing sequence orchestrates feeding.

Feeding requires sophisticated orchestration of neural processes to satiate appetite in natural, capricious settings. However, the complementary roles of discrete neural populations in orchestrating distinct behaviors and motivations throughout the feeding process are largely unknown. Here, we delineate the behavioral repertoire of mice by developing a machine-learning-assisted behavior tracking system and show that feeding is fragmented and divergent motivations for food consumption or environment exploration compete throughout the feeding process. An iterative activation sequence of agouti-related peptide (AgRP)-expressing neurons in arcuate (ARC) nucleus, GABAergic neurons in the lateral hypothalamus (LH), and in dorsal raphe (DR) orchestrate the preparation, initiation, and maintenance of feeding segments, respectively, via the resolution of motivational conflicts. The iterative neural processing sequence underlying the competition of divergent motivations further suggests a general rule for optimizing goal-directed behaviors.

An Infrared Touch System for Automatic Behavior Monitoring.

Key requirements of successful animal behavior research in the laboratory are robustness, objectivity, and high throughput, which apply to both the recording and analysis of behavior. Many automatic methods of monitoring animal behavior meet these requirements. However, they usually depend on high-performing hardware and sophisticated software, which may be expensive. Here, we describe an automatic infrared behavior-monitor (AIBM) system based on an infrared touchscreen frame. Using this, animal positions can be recorded and used for further behavioral analysis by any PC supporting touch events. This system detects animal behavior in real time and gives closed-loop feedback using relatively low computing resources and simple algorithms. The AIBM system automatically records and analyzes multiple types of animal behavior in a highly efficient, unbiased, and low-cost manner.

Inhibitory effect of antioxidant extracts from various potatoes on the proliferation of human colon and liver cancer cells.

Antioxidant extracts from 5 potato lines were evaluated for antioxidant activity, total phenolics, chlorogenic acid, anthocyanin content, and in vitro anticancer capacity. Analysis showed that Mexican wild species S. pinnatisectum had the highest antioxidant activity, total phenolic, and chlorogenic acid content. The proliferation of colon cancer and liver cancer cells was significantly inhibited by potato antioxidant extracts. The highest antiproliferative activity was observed in extracts of S. pinnatisectum and the lowest in Northstar. An inverse correlation was found between total phenolics and the EC(50) of colon cancer cell (R(2) = 0.9303), as well as liver cancer cell proliferation (R(2) = 0.8992). The relationship between antioxidant activity and EC(50) of colon cancer/liver cancer cell proliferation was significant (R(2) = 0.8144; R(2) = 0.956, respectively). A significant difference in inhibition of cancer cells (P < 0.01) existed between the 3 polyphenols: chlorogenic acid, pelargonidin chloride, and malvidin chloride, suggesting that chlorogenic acid was a critical factor in the antiproliferation of colon cancer and liver cancer cells.

[Field observation on the effect of low-sodium and high-potassium salt substitute on blood pressure in the rural community-based population in China].

OBJECTIVE: To investigate the effect of commercial low-sodium and high-potassium salt substitutes on blood pressure in the rural community-based population in China. METHODS: We conducted a quasi-experiment on 411 adults, who were 30 to 60 years of age, in 2 rural communities from Laiwu city in Shandong province of China on data from blood pressure screening. The subjects were divided into 2 groups: high blood pressure (HBP) and non-HBP (NHBP). Both groups and their family members took a low-sodium and high-potassium salt substitute for 3 months to replace the normal salt in their bodies. Blood pressure (BP) and 24-hour urinary sodium and potassium were measured regularly in the 2 groups. RESULTS: There was a continuously decreasing trend for BP at the end of the first month. Three months later, the mean BP decreased by 7.4 mm Hg (1 mm Hg = 0.133 kPa, t = 10.096, P = 0.000) for SBP and 3.8 mm Hg (t = 8.017, P = 0.000) for DBP in the HBP group, when compared to a 1.2 mm Hg (t = 2.507, P = 0.007) decrease on SBP and 1.0 mm Hg (t = 2.987, P = 0.002) on DBP in the NHBP group. The mean urinary sodium had a decrease of 15.5 mmol/24 h (t = 1.803, P = 0.037), but the urinary potassium increased by 4.2 mmol/24 h (t' = 2.132, P = 0.018). The result of urinary sodium appeared to be as follows: potassium ratio (Na(+)/K(+)) decreased by 1.2 (t = 2.786, P = 0.003) in the HBP group. However, in NHBP group, the mean urinary sodium decreased by 1.7 mmol/24 h (t = 0.211, P = 0.417) and urinary potassium increased by 3.7 mmol/24 h (t' = 2.207, P = 0.015), together with the decrease of Na(+)/K(+) by 0.7 (t = 1.818, P = 0.036). CONCLUSION: Results from our study clearly demonstrated that the intake of low-sodium and high-potassium salt substitute could effectively reduce the BP with good compliance among adults in the rural community-based population in China. This was an effective but non-medical method to prevent and control the high blood pressure.

Associations of fibrinogen with metabolic syndrome in rural Chinese population.

AIM: Metabolic syndrome (MS) comprises a constellation of various metabolic abnormalities, but insulin resistance is considered the basis of the syndrome. The relationship of plasma fibrinogen with MS and insulin resistance remains inconclusive. The aim of this study was to assess whether plasma fibrinogen levels were associated with MS and insulin resistance in a rural population of China. METHODS: Participants were selected using a multi-stage random-sampling method. A standardized interview was conducted by trained personnel, and "metabolic syndrome" was defined according to the Chinese Diabetes Association. Insulin resistance was assessed by fasting insulin and HOMA-IR. Associations of fibrinogen levels with components of MS and insulin resistance were determined using correlation analysis and multiple linear regression analyses. RESULTS: A total of 1,792 participants (M: 815, W: 977) aged 15 to 85 years was studied. Adjusted mean fibrinogen concentration increased with increases in the number of MS components (p<0.001). Multiple linear regression analyses showed that fibrinogen concentration was significantly and positively associated with age, DBP and negatively with physical exercise and HDL-C in males and females, and positively with WHR, LogTG, and FPG in females. No statistically significant association between fibrinogen and insulin resistance was observed. CONCLUSIONS: Fibrinogen was significantly associated with MS, independent of major confounders. Insulin resistance showed an inconsistent association with fibrinogen.

[Study on the molecular mechanism of apoptosis in esophageal cancer cells induced by soybean isoflavone].

OBJECTIVE: To investigate the function of apoptosis in esophageal cancer cells induced by soybean isoflavone, and the relation between this apoptosis and expression of bcl-2 and bax. METHODS: In vitro experiments, MTT assay was used to determine the cell growth inhibitory rate. Transmission electron microscope and TUNEL staining method were used to quantitatively and qualitatively detect the apoptosis status of esophageal cancer cell line EC-9706 before and after the soybean isoflavone treatment. Immunohistochemical staining and reverse transcription-polymerase chain reaction were used to detect the expression of apoptosis-regulated gene bcl-2 and bax. RESULTS: Soybean isoflavone inhibited the growth of esophageal cancer cell line EC-9706 in a dose- and time-dependent manner. Soybean isoflavone induced EC-9706 cells to undergo apoptosis with typically apoptotic characteristics, including morphological changes of chromatin condensation, chromatin crescent formation, nucleus fragmentation and apoptotic body formation by transmission electron microscope and staining positive cells, using TUNEL assay. Soybean isoflavone reduced the expression of apoptosis-regulated gene bcl-2, and improving the expression of apoptosis-regulated gene bax. CONCLUSION: Soybean isoflavone seemed to be able to induce the apoptosis in esophageal cancer. This type of apoptosis might be mediated by down-expression of apoptosis-regulated gene bcl-2 and up-expression of apoptosis-regulated gene bax.