Place Navigation Research Articles

Navigation of Robot-Formation via Overlap-Induced Equilibrium Points in Uncertain Environments

We propose a novel reactive algorithm for a multi-robot formation navigating from its starting point to its destination in geometrically changing non-convex environments containing dynamic obstacles that move stochastically. Taking formation’s buffer into consideration, the proposed algorithm estimates the optimal velocity by means of minimizing collision threats from obstacles to the formation. It considers the obstacles in pairs so that the formation crosses the gap between every involved pair of obstacles. At every time step, this algorithm is executed in four phases: 1) optimal velocity estimation using a probabilistic model; 2) topological trajectory decision; 3) optimal waypoint (crossing point) determination; and 4) real-time optimal velocity determination. Compared to existing algorithms, the simulation shows that our algorithm is robust and has significant improvement. <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Note to Practitioners</i> —This paper was motivated by the problem of formation navigation in places containing a large number of moving objects such as human beings and other vehicles. Existing approaches either do not forecast the probability of collision, or do not explicitly consider a certain comfort or safety distance to maintain. This paper quantifies the expectation of objects getting “too close” to the formation before collision as a numerical collision forecast, where the future motions of objects are unknown: this allows a formation to navigate by acquiring least environment information. From this expectation, by considering the formation to be moving between pairs of these objects, the optimal path to the destination for the formation is computed. Our approach is proved by the simulation to have significant improvement compared to the existing approaches. In future research, we will consider more ways to avoid obstacles such as formation rotation and waiting.

Electroacupuncture at "Baihui"（GV20） and "Yongquan"（KI1） improves learning-memory ability of APP/PS1 double transgenic mice by regulating endosomal-lysosomal system

To explore the mechanism of electroacupuncture（EA） in improving learning-memory ability in Alzheimer's disease （AD） mice from the perspective of endosomal-lysosomal system. Male APP/PS1 transgenic mice were randomly divided into model group and EA group （n=10 in each group） and 10 male C57BL/6 wild mice were taken as the normal group. EA （1 Hz/50 Hz, 1 mA） was applied at bilateral "Yongquan"（KI1） and acupuncture was applied at "Baihui" （GV20） for 15 min. The mice of the model and normal groups were subjected to restriction with the same method as those of the EA group for 15 min. The treatment was conducted once every other day for 6 weeks. The spatial learning-memory ability （shown by escape latency of place navigation test and the time of crossing the target platform and total swimming distance in the target quadrant in 1 min of spatial probe test ） was detected by Morris water maze test. The immunoactivity of senile plaques （SP） in the hippocampus tissue was detected by immunohistochemistry. The ultrastructural characters of hippocampal neurons were observed by transmission electron microscope, and the expression levels of Ras-related protein 5 （Rab5）, Ras-related protein 7 （Rab7） and cathepsin D （CTSD） in the hippocampus were detected by Western blot, separately. Compared with the normal group, the escape latency, SP immunoactivity, and protein expression levels of Rab5, Rab7 and CTSD were significantly increased （P<0.05, P<0.01）, while the number of crossing the original platform and the total swimming distance in the platform quadrant were considerably reduced （P<0.05） in the model group. In contrast to the model group, the EA group had a marked decrease in the escape latency, SP immunoactivity, and protein expression levels of Rab5, Rab7 and CTSD （P<0.05, P<0.01）, and a striking increase in the number of crossing the original platform and the swimming distance in the platform quadrant （P<0.05）. Results of transmission electron microscope showed an accumulation of endosome, lysosome, and endolysosomes in the hippocampal neurons in the model group, which was evidently milder in the EA group. EA of GV20 and KI1 can improve the learning-memory ability of AD mice, which may be related to its function in reducing hippocampal Aβ deposition and down-regulating endosomal-lysosomal system activity.

Electroacupuncture at "Baihui"（GV20） and "Yongquan"（KI1） improves learning-memory ability of APP/PS1 double transgenic mice by regulating endosomal-lysosomal system

To explore the mechanism of electroacupuncture（EA） in improving learning-memory ability in Alzheimer's disease （AD） mice from the perspective of endosomal-lysosomal system. Male APP/PS1 transgenic mice were randomly divided into model group and EA group （n=10 in each group） and 10 male C57BL/6 wild mice were taken as the normal group. EA （1 Hz/50 Hz, 1 mA） was applied at bilateral "Yongquan"（KI1） and acupuncture was applied at "Baihui" （GV20） for 15 min. The mice of the model and normal groups were subjected to restriction with the same method as those of the EA group for 15 min. The treatment was conducted once every other day for 6 weeks. The spatial learning-memory ability （shown by escape latency of place navigation test and the time of crossing the target platform and total swimming distance in the target quadrant in 1 min of spatial probe test ） was detected by Morris water maze test. The immunoactivity of senile plaques （SP） in the hippocampus tissue was detected by immunohistochemistry. The ultrastructural characters of hippocampal neurons were observed by transmission electron microscope, and the expression levels of Ras-related protein 5 （Rab5）, Ras-related protein 7 （Rab7） and cathepsin D （CTSD） in the hippocampus were detected by Western blot, separately. Compared with the normal group, the escape latency, SP immunoactivity, and protein expression levels of Rab5, Rab7 and CTSD were significantly increased （P<0.05, P<0.01）, while the number of crossing the original platform and the total swimming distance in the platform quadrant were considerably reduced （P<0.05） in the model group. In contrast to the model group, the EA group had a marked decrease in the escape latency, SP immunoactivity, and protein expression levels of Rab5, Rab7 and CTSD （P<0.05, P<0.01）, and a striking increase in the number of crossing the original platform and the swimming distance in the platform quadrant （P<0.05）. Results of transmission electron microscope showed an accumulation of endosome, lysosome, and endolysosomes in the hippocampal neurons in the model group, which was evidently milder in the EA group. EA of GV20 and KI1 can improve the learning-memory ability of AD mice, which may be related to its function in reducing hippocampal Aβ deposition and down-regulating endosomal-lysosomal system activity.

Error-prone protein synthesis recapitulates early symptoms of Alzheimer disease in aging mice.

Age-related neurodegenerative diseases (NDDs) are associated with the aggregation and propagation of specific pathogenic protein species (e.g., Aβ, α-synuclein). However, whether disruption of synaptic homeostasis results from protein misfolding per se rather than accumulation of a specific rogue protein is an unexplored question. Here, we show that error-prone translation, with its frequent outcome of random protein misfolding, is sufficient to recapitulate many early features of NDDs, including perturbed Ca2+ signaling, neuronal hyperexcitability, and mitochondrial dysfunction. Mice expressing the ribosomal ambiguity mutation Rps9 D95N exhibited disrupted synaptic homeostasis resulting in behavioral changes reminiscent of early Alzheimer disease (AD), such as learning and memory deficits, maladaptive emotional responses, epileptiform discharges, suppressed circadian rhythmicity, and sleep fragmentation, accompanied by hippocampal NPY expression and cerebral glucose hypometabolism. Collectively, our findings suggest that random protein misfolding may contribute to the pathogenesis of age-related NDDs, providing an alternative framework for understanding the initiation of AD.

Effects of pre-moxibustion on expression of phosphorylated Tau protein and related protein kinases in hippocampal CA3 region of AD rats

To observe the effect of pre-moxibustion at "Baihui"(GV20), "Shenshu"(BL23) and "Zusanli"(ST36) on expression of Tau protein and related protein kinases as glycogen synthase kinase-3β (GSK-3β), etc. in the hippocampal CA3 region of Alzheimer's disease (AD) rats, so as to explore its mechanism underlying prevention and treatment of AD cognitive impairment. Male SD rats were randomly divided into 4 groups: normal control, sham operation， model and pre-moxibustion，with 9 rats in each group. Rats of the pre-moxibustion group received moxibustion of GV20, BL23 and ST36 for 15 min, once a day, 6 days a week for 3 weeks. After completion of moxibustion, the AD model was reproduced by injection of amyloid beta-peptide 25-35(Aβ 25-35) aggregation solution 1 μL (5 μg/μL) into the bilateral hippocampus, rats of the sham operation group received injection of the same dose of normal saline into the hippocampus. The spatial learning-memory ability was detected using Morris water maze test, and changes of the ultrastructure of hippocampal neurons were observed using electron microscope, and those of histopathological changes of hippocampus tissue observed using hematoxylin eosin (H.E.) staining. The expression levels of hippocampal GSK-3β, p-Tau, CDK5 and Synapsin I proteins were detected by Western blot and immunohistochemistry, respectively. No significances were found between the normal control and sham groups in all the indexes (P>0.05). Compared with the control group, the escape latency of place navigation test of Morris water maze test, expression of GSK-3β and CDK5 and the immunoactivity of GSK-3β, CDK5 and p-Tau were significantly increased (P<0.01), and the residence time in the platform quadrant and the number of platform crossing of spatial prob test and the expression of Synapsin Ⅰ significantly reduced in the model group (P<0.01). Following the intervention, the increase of escape latency, expression of GSK-3β and CDK5 and the immunoactivity of GSK-3β, CDK5 and p-Tau, and the decrease of residence time in the platform quadrant, number of platform crossing and the expression of Synapsin Ⅰ were reversed in the pre-moxibustion group (P<0.05, P<0.01). Outcomes of ultrastructure and histopathological observations respectively showed edema of hippocampal nerve cells at varying degrees, moderate edema of the cytoplasma, chromatin condensation at the edge of the nucleus, partial mitochondrial vacuole-like degeneration, fracture of tubular crest, edema and expansion of Golgi body, disappearance of polarity, fracture of the rough endoplasmic reticulum, degeneration of ribosome and partial myelin axon and reduced synaptic vesicles in the presynaptic capsule; and reduced number of neurons with shrank body, disappearance of nucleolus and blurred nuclear boundary and vacuole-like degeneration in some of them in the model group, which were relatively milder in the pre-moxibustion group. Pre-moxibustion at GV20, BL23 and ST36 plays a role in slowing down the occurrence and development of cognitive impairment in AD rats, which may be related to its functions in inhibiting tau protein hyperphosphorylation and reducing the expression of some related protein kinases in the hippocampus.

Findings From A Qualitative Field Study with An Autonomous Robot in Public: Exploration of User Reactions and Conflicts

Soon service robots will be employed in public spaces with frequent human-robot interaction (HRI). To achieve a safe, trustworthy and acceptable HRI, service robots need to be equipped with interaction strategies suitable for the robot, user, and context. To gain realistic insights into the initial user reactions and challenges that arise when a mechanoid, autonomous service robot in public is applied, a field study with three data sources was conducted. In a first step, lay users’ intuitive reactions to a cleaning robot at a train station were observed (N = 344). Second, passersby’s preferences for HRI interaction strategies were explored in interviews (n = 54). As a third step, trust and acceptance of the robot were assessed with questionnaires (n = 32). Identified challenges were social robot navigation in crowded places also applicable to vulnerable passersby, inclusive communication modalities, information of staff and public about the service robot application and the need for conflict resolution strategies to avoid an inefficient robot (e.g., testing behavior, path is blocked). This study provides insights into naive HRI in public and illustrates challenges, provides recommendations supported by literature and highlights aspects for future research to inspire a research agenda in the field of public HRI.

Place recognition and navigation of outdoor mobile robots based on random Forest learning with a 3D LiDAR

Place recognition and navigation of outdoor mobile robots based on random Forest learning with a 3D LiDAR

Nitric oxide impairs spatial learning and memory in a rat model of Alzheimer’s disease via disturbance of glutamate response in the hippocampal dentate gyrus during spatial learning

Nitric oxide (NO)-dependent pathways may play a significant role in the decline of synaptic and cognitive functions in Alzheimer’s disease (AD). However, whether NO in the hippocampal dentate gyrus (DG) is involved in the spatial learning and memory impairments of AD by affecting the glutamate (Glu) response during these processes is not well-understood. Here, we prepared an AD rat model by long-term i.p. of D-galactose into ovariectomized rats, and then the effects of L-NMMA (a NO synthase inhibitor) on Glu concentration and amplitude of field excitatory postsynaptic potential (fEPSP) were measured in the DG region during the Morris water maze (MWM) test in freely-moving rats. During the MWM test, compared with the sham group, the escape latency was increased in the place navigation trial, and the percentage of time spent in target quadrant and the number of platform crossings were decreased in the spatial probe trial, in addition, the increase of fEPSP amplitude in the DG was significantly attenuated in AD group rats. L-NMMA significantly attenuated the spatial learning and memory impairment in AD rats, and reversed the inhibitory effect of AD on increase of fEPSP amplitude in the DG during the MWM test. In sham group rats, the Glu level in the DG increased significantly during the MWM test, and this response was markedly enhanced in AD rats. Furthermore, the response of Glu in the DG during spatial learning was recovered by microinjection of L-NMMA into the DG. Our results suggest that NO in the DG impairs spatial learning and memory and related synaptic plasticity in AD rats, by disturbing the Glu response during spatial learning.

Neuroprotective Effects of Probiotic-Supplemented Diet on Cognitive Behavior of 3xTg-AD Mice.

Alzheimer's disease (AD) is recognized as one of the most common types of senile dementia. AD patients first suffer memory loss for recent events (short-term memory impairment). As the disease progresses, they are deprived of self-awareness. This study aims to explore the effects of a probiotic-supplemented diet on the cognitive behaviors and pathological features of mouse models of Alzheimer's disease (AD). Mice in the control group and the 3xTg-AD group were fed a regular diet and a probiotic-supplemented diet, respectively, for 20 weeks. Behavioral experiments like Morris's water maze and Y maze were conducted. Then, feces of mice were collected for 16S sRNA gene sequencing for microorganisms. In the end, soluble and insoluble Aβ40 and Aβ42 in the hippocampus and cortex of mice in each group were quantitatively analyzed with a double-antibody Sandwich ELISA. The expression levels of tau protein and gliocyte in the hippocampus and cortex were detected using the Western Blot method. The result of the Morris water maze experiment indicated that, in the place navigation test, the mice in the 3xTg-AD group experienced a significant decline in the learning ability and a longer escape latency and in the space exploration test, the swimming time of mice in the 3xTg-AD group in the target quadrant decreased and after being treated with the probiotic diet, mice in the 3xTg-AD group had improved learning and memory ability. The result of Y maze showed that the probiotic diet can improve the spontaneous alternation accuracy of mice in the 3xTg-AD group. The result of 16s rRNA gene sequencing showed that, compared with mice in the WT group, those in the 3xTg-AD group experienced a change in the intestinal flora. The Western Blot result displayed a decreased expression level of tau (pS202) (P < 0.05) and decreased expression levels of Iba-1 and GFAP (P < 0.05). The result of the ELISA experiment showed decreased levels of soluble and insoluble Aβ40 and Aβ42 in 3xTg-AD mice (P < 0.05). In conclusion, a probiotic diet can prevent and treat AD by improving the intestinal flora of 3xTg-AD.

Navigation using global or local reference frames in rats with medial and lateral entorhinal cortex lesions

The medial (MEC) and the lateral (LEC) regions of the entorhinal cortex send a major input to the hippocampus and have been proposed to play a foremost role in combining spatial and non-spatial attributes of episodic memory. In addition, it has been recently suggested that the MEC is involved in the processing of information in a global reference frame and the LEC in the processing of information in a local reference frame. Whether these putative functions could be generalized to navigation contexts has not been established yet. To address this hypothesis, rats with MEC or LEC NMDA-induced lesions were trained in two versions of a navigation task in the water maze, a global cue condition in which they had to use distal room cues and a local cue condition in which they had to use 3 objects placed in the pool. In the global cue condition, MEC-lesioned rats exhibited slower acquisition and were not able to precisely locate the submerged platform during the probe trial. In contrast LEC-lesioned rats exhibited control-like performance. In the local cue condition, navigational abilities were spared in both lesion groups. In addition when the 3 different objects were replaced by 3 identical objects, all groups maintained their navigation accuracy suggesting that the identity of objects is not crucial for place navigation. Overall, the results indicate that the MEC is necessary for place navigation using a global reference frame. In contrast, navigation using a local reference frame does not require the LEC nor the MEC.

Effect of electroacupuncture on learning-memory ability and expression of IL-1β, IL-6 and TNF-α in hippocampus and spleen in mice with Alzheimer's disease

To explore the effect of electroacupuncture (EA) on the ability of spatial learning-memory and the expression of IL-1β, IL-6 and TNF-α in the hippocampus and spleen tissues and the number of hippocampal neurons and spleen lymphocytes in Alzheimer's disease (AD) mice, so as to study its mechanisms underlying improvement of AD. Twenty-four SAMP8 mice were randomly and equally divided into AD model, EA and medication groups, and 8 SAMR1 mice were used as the control group. EA (2 Hz, 0.1 mA) was applied to "Baihui"(GV20) and "Yintang"(EX-HN3) for 20 min in the EA group, and intragastric administration of donepezil hydrochloride (0.92 mg/kg) was applied in the medication group, once daily for 15 d. The learning-memory ability was determined by Morris water maze task, and the histopathological changes of hippocampus were observed after H.E. staining, followed by determining neurons and the number of splenic lymphocytes. The expression levels of IL-1β, IL-6 and TNF-α in the hippocampus and spleen were detected by immunohistochemistry and Western blot, respectively. After mode-ling, the escape latency of place navigation test in the Morris water maze, the spleen index, immunoactivity and expression levels of IL-1β, IL-6 and TNF-α proteins in the hippocampus and spleen tissues were significantly increased (P<0.05, P<0.01). Compared with the model group, the escape latency, spleen index, immunoactivity and expression levels of IL-1β, IL-6 and TNF-α proteins in both hippocampus and spleen were significantly down-regulated in the medication (except the escape latency) and EA groups (P<0.01, P<0.05). The effect of EA was evidently superior to that of medication in shortening the escape latency, lowering the spleen index, and immunoactivity of hippocampal IL-6 and splenic TNF-α immunoactivity (P<0.01, P<0.05). Outcomes of H.E. staining showed disordered arrangement of neurons with nuclear pyknosis or apoptosis in partial neurons in the hippocampus, and thickened and swollen spleen capsule tissue with loose structure and an increased number of lymphocytes in the model group, which was relatively milder in the EA and medication groups. EA can improve the learning-memory ability of AD mice, which may be associated with its effect in relieving the inflammation reaction in the hippocampus and spleen tissues.

The Impact of Neonatal Methamphetamine on Spatial Learning and Memory in Adult Female Rats.

The present study was aimed at evaluating cognitive changes following neonatal methamphetamine exposure in combination with repeated treatment in adulthood of female Wistar rats. Pregnant dams and their pups were used in this study. One half of the offspring were treated indirectly via the breast milk of injected mothers, and the other half of pups were treated directly by methamphetamine injection. In the group with indirect exposure, mothers received methamphetamine (5 mg/ml/kg) or saline (1 ml/kg) between postnatal days (PD) 1–11. In the group with direct exposure, none of the mothers were treated. Instead, progeny were either: (1) treated with injected methamphetamine (5 mg/ml/kg); or (2) served as controls and received sham injections (no saline, just a needle stick) on PD 1–11. Learning ability and memory consolidation were tested on PD 70–90 in the Morris Water Maze (MWM) using three tests: Place Navigation Test, Probe Test, and Memory Recall Test. Adult female progeny were injected daily, after completion of the last trial of MWM tests, with saline or methamphetamine (1 mg/ml/kg). The effects of indirect/direct neonatal methamphetamine exposure combined with acute adult methamphetamine treatment on cognitive functions in female rats were compared. Statistical analyses showed that neonatal drug exposure worsened spatial learning and the ability to remember the position of a hidden platform. The study also demonstrated that direct methamphetamine exposure has a more significant impact on learning and memory than indirect exposure. The acute dose of the drug did not produce any changes in cognitive ability. Analyses of search strategies (thigmotaxis, scanning) used by females during the Place Navigation Test and Memory Recall Test confirmed all these results. Results from the present study suggested extensive deficits in learning skills and memory of female rats that may be linked to the negative impact of neonatal methamphetamine exposure.

Discussion of the promising effect of electroacupuncture on cognitive improvement in D-galactose-induced aging rats based on NLRP3-ASC-Caspase-1 signaling pathway

To investigate the effect of electroacupuncture (EA) on cognitive function in D-galactose (D-gal)-induced aging rats, and the correlation between the effect and nucleotide-binding oligomerization domain (NOD)-like receptor protein 3 (NLRP3)-ASC-Caspase-1 signaling pathway. Forty-six male Sprague-Dawley (SD) rats were randomly divided into a control group (n=10), a model group (n=12), an EA-7 d group (n=12) and an EA-21 d group (n=12). Except the control group, the other three groups received 42 consecutive days of intraperitoneal injection of D-gal to establish aging rat models with cognitive dysfunction. The control group received the same amount of normal saline via intraperitoneal injection. Two EA groups were given EA therapy for 21 consecutive days (began from the 22nd day of modeling) or 7 consecutive days (began from the 36th day of modeling) accordingly at Dazhui (GV 14), Baihui (GV 20), Shenshu (BL 23) and Zusanli (ST 36). After modeling/intervention, all four groups received behavioral evaluations by Morris water maze (MWM) test, novel object recognition (NOR) test and step-down passive avoidance (SDPA) test followed by the Western blot (WB) detection of the expression levels of hippocampal NLRP3 inflammasome-associated proteins NLRP3, ASC and Caspase-1. MWM (place navigation test, PNT) results showed that the escape latency in the model group was significantly longer than that in the other three groups (P 0.05). From the 2nd day to the 4th day of the test, there was no significant difference between the EA-21 d group and the control group (P>0.05) in the escape latency; the escape latency was significantly shorter in the EA-21 d group than in the model group and the EA-7 d group (P 0.05). NOR results showed that there was no significant difference in the recognition ratio between the EA-7 d group and the EA-21 d group (P>0.05), and the recognition ratio was significantly higher in the two EA groups than in the model group (P 0.05). The model group had the shortest step-down latency, followed by the EA-7 d group, the EA-21 d group and the control group in order (P 0.05). NLRP3 inflammasome may be involved in the development of cognitive decline in aging rats; 7 consecutive days of EA intervention can partially improve the cognitive impairment in aging rats though the effect is rather limited; 21 consecutive days of EA intervention may improve the learning and memory abilities in aging rats via down-regulating the expression levels of NLRP3 inflammasome-associated proteins in hippocampus.

Electroacupuncture improves learning-memory ability possibly by suppressing apoptosis and down-regulating expression of apoptosis-related proteins in hippocampus and cerebral cortex in immature mice with Alzheimer's disease

To investigate the effect of electroacupuncture (EA) at "Baihui"(GV20), "Fengfu"(GV16) and bilateral "Shenshu"(BL23) on learning-memory ability, apoptosis in the hippocampus and expression of Aβ, Caspase 3, Bax and Bcl-2 proteins in the hippocampus and cerebral cortex in immature mice with Alzheimer's disease (AD), so as to explore its mechanism underlying improvement of AD. Forty APP/PS1 transgenic male young mice were equally randomized into model and EA groups and 20 C57BL/6J male young mice were used as the normal control. EA (10 Hz, about 2 mA) was applied to GV20-BL23 and GV16-BL23 for 20 min, once daily, 6 days a week for 16 weeks. The Morris water maze swimming test was used to evaluate the animals' learning-memory ability. Congo red staining and immunohistochemical staining were used to detect senile plaques in the hippocampus (dentate gyrus) and cerebral cortex tissues. Terminal deoxynucleotidyl transferase-mediated dUTP Nick-end Labeling (TUNEL) was used to detect the cellular apoptosis of hippocampus. The expression levels of apoptosis related factors Caspase 3, Bax and Bcl-2 were detected by Western blot. After modeling, the escape latency of place navigation test of Morris water maze swimming tasks was significantly increased (P<0.05), while the number of platform crossing and residence time in the platform quadrant of spatial exploration test were significantly decreased in the model group in contrast to the normal control group (P<0.05). The number of apoptotic cells in the hippocampus and expression levels of Aβ, Caspase 3 and Bax proteins in the hippocampus and cerebral cortex were significantly up-regulated in the model group relevant to the normal control group (P<0.05). Following EA intervention, the escape latency of place navigation test of Morris water maze swimming tasks was significantly decreased (P<0.05), while the number of platform crossing and residence time in the platform quadrant of spatial exploration test were significantly increased in the EA group in contrast to the model group (P<0.05). The hippocampal apoptotic cells, the expression of Aβ, Caspase 3 and Bax proteins in hippocampus and cerebral cortex were evidently down-regulated in the EA group in contrast to the model group (P<0.05). Whereas the ratio of Bcl-2/Bax was significantly decreased in the model group relevant to the normal control group (P<0.05) and considerably increased in the EA group in contrast to the model group (P<0.05). No significant changes were found in the expression levels of Bcl-2 after modeling and after EA intervention (P>0.05). EA of GV20, GV16 and BL23 can effectively improve the learning-memory ability in AD mice, which may be related to its function in inhibiting neuronal apoptosis in the hippocampus and down-regulating the expression levels of Aβ, Caspase 3 and Bax proteins in both hippocampus and cerebral cortex.

Effect of electroacupuncture of different acupoint groups on learning-memory ability and expression of IL-1β and TNF-α in hippocampus and prefrontal cortex in rats with Alzheimer's disease

To compare the effect of electroacupuncture (EA) of acupoint group for "reinforcing the kidney and regulating Governor Vessel" and acopoint group for "reinforcing the kidney and lung and regulating Governor Vessel" on lear-ning-memory ability and expression of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) proteins in the hippocampus and prefrontal cortex (PFC) in Alzheimer's disease （AD） rats, so as to explore the efficacy of the two acupoint groups and mechanisms underlying improvement of AD. Forty male SD rats were randomly divided into control, sham operation, model, "Baihui" + "Shenshu" (GV20+BL23, for "reinforcing the kidney and regulating Governor Vessel") EA and GV20+BL23+ "Feishu" (BL13, GV20+BL23+BL13, for "reinforcing the kidney and lung and regulating Governor Vessel") EA groups (n=8 rats in each group). The AD model was established by bilateral injection of amyloid β peptide （Aβ25-35，10 μL) into bilateral hippocampus, and rats of the sham operation group received injection of normal saline. After successful establishment of the model，EA (2 Hz, 2 mA) was applied to these acupoints for 15 min, once daily for 10 days. Then, the learning-memory ability was assessed by using Morris water maze tests, and the expression levels of TNF-α and IL-1β proteins in the PFC and hippocampus tissues were detected by using Western blot. Following modeling, the average escape latency of place navigation test were significantly increased (P<0.05) and the platform crossing times of spatial probe test was significantly decreased in the model group than in the control and sham operation groups (P<0.05). The expression levels of IL-1β and TNF-α proteins in the PFC and hippocampus were apparently up-regulated in the model group than in the control and the sham operation groups (P<0.000 1, P<0.001, P<0.01). After the intervention, the increase of the average escape latency and expression of IL-1β and TNF-α in the PFC and hippocampus, and the decrease of space exploration test were revised in both GV20+BL23 EA and GV20+BL23+BL13 EA groups (P<0.05,P<0.01). No significant differences were found between the GV20+BL23 and GV20+BL23+BL13 EA groups in the above mentioned indexes (P>0.05). EA of both GV20+BL23 and GV20+BL23+BL13 acupoint can improve learning-memory ability of AD rats, which is associated with their effects in down-regulating the expression of IL-1β and TNF-α in the PFC and hippocampus to reduce inflammatory reaction. There were no significant differences between the two acupoint groups in the therapeutic effects.

Effect of electroacupuncture combined with Donepezil on learning-memory ability and expression of hippocampal β-amyloid clearance-related genes in SAMP8 mice

To investigate the effect of electroacupuncture (EA) combined with Donepezil on learning-memory ability and gene expression of β-amyloid (Aβ) clearance-related factors in the hippocampus in senescence-accelerated mouse prone 8 (SAMP8) mice, so as to explore their synthetic effect in improving dementia of Alzheimer's disease (AD)．. Male SAMP8 mice (30-week-old) were randomly divided into model, medication and EA＋medication groups (n＝6 mice in each group), and other 6 senescence-resistant 1 (SAMR1) mice were used as the control group. Mice of the medication and EA＋medication group received gavage of Donepezil (1.3 mg•kg－1•d－1) once daily for 4 weeks. EA (2 Hz, 1 mA) was applied to "Baihui"(GV20) and "Yintang" (EX-HN3) for 15 min, once daily, 6 days a week for 4 weeks for rats in the EA＋medication group. The Morris water maze (MWM) task (including place navigation tests and space exploration trials) was used to assess the mouse's learning-memory ability. Histopathological changes of hippocampus tissue were observed by H．E. staining. The expression levels of matrix metalloprotein 9 (MMP-9), low density lipoprotein receptor-related protein-1 (LRP-1), P-glycoprotein (Pgp, an important drug transporter responsible for multidrug resistance), Claudin-5 (a component of tight junction strands that serves as a physical barrier to prevent solutes and water from passing freely through the paracellular space between epithelial or endothelial cell sheets of blood-brain barrier, BBB) and Aβ mRNAs of the hippocampus tissue were detected by quantitative real-time PCR. Compared with the control group, the average escape latency of place navigation tests, and the expression levels of MMP-9 and Aβ mRNAs were significantly increased (P<0.01), and the number of platform quadrant-crossing times of space exploration trials, and the expression levels of LRP-1, Pgp and Claudin-5 mRNAs considerably decreased in the model group (P<0.01). After the intervention, the learning-memory ability was significantly improved in the medication and EA＋medication groups (P<0.01，P<0.05), the expression levels of Aβ mRNAs in the medication and EA＋medication groups and MMP-9 mRNA in the EA＋medication group were obviously down-regulated (P<0.01), and those of LRP-1 and Pgp mRNAs in the medication and EA＋medication groups and Claudin-5 mRNA in the EA＋medication group were remarkably up-regulated (P<0.05, P<0.01). The therapeutic effect of EA＋medication was apparently superior to that of simple medication in shortening the escape latency (P<0.05，P<0.01) and in down-regulating the expression of MMP-9 and Aβ mRNAs(P<0.01), and in increasing the number of platform quadrant-crossing times(P<0.01), and expression levels of LRP-1, Pgp and Claudin-5 mRNAs (P<0.01). H．E. staining showed scatted and loose arrangement of neurons in the hippocampus, with reduction of number of cell layers and unclear nucleoli, which was relatively milder in the medication and EA＋medication groups. EA can enhance the effect of Donepezil in improving learning-memory ability in AD mice possibly by regulating expression of MMP-9, LRP-1, Pgp and Claudin-5 mRNAs and strengthening the effect of Donepezil in transporting Aβ via BBB.

Effects of Aberrant miR-384-5p Expression on Learning and Memory in a Rat Model of Attention Deficit Hyperactivity Disorder.

Attention deficit hyperactivity disorder (ADHD) is a common neuropsychiatric disorder characterized by inattention, hyperactivity, and impulsivity. It may be accompanied by learning difficulties and working memory deficits. Few studies have examined the role of miRNAs in cognitive dysfunction in ADHD. This study investigated the effects of aberrant miR-384-5p expression on learning and memory in a widely used ADHD rat model. Lentiviral vectors were injected into the lateral ventricles of the rats to increase or decrease miR-384-5p level. To determine whether aberrant miR-384-5p expression affects learning and memory, spontaneous activity and cognitive function were assessed with the open field and Morris water maze tests. In the place navigation experiment of the Morris water maze test, time, and total swimming distance to reach the platform decreased compared to the control group when miR-384-5p was overexpressed, whereas down-regulation of miR-384-5p had the opposite effect. There were no obvious changes in brain tissue morphology following miR-384-5p overexpression or inhibition; however, dopamine (DA) receptor D1 (DRD1) level has decreased and increased, respectively, in the prefrontal cortex (PFC). The luciferase activity of the wild-type DRD1 group has decreased in luciferase reporter assay. Cyclic AMP response element-binding protein (CREB) phosphorylation has increased, and DA transporter (DAT) level has decreased in the PFC of spontaneously hypertensive rats (SHR) by miR-384-5p overexpression. On the other hand, miR-384-5p suppression increased DRD1 and decreased DAT and CREB protein levels relative to control rats. These findings suggest that miR-384-5p may play a critical role in learning and memory impairment in ADHD.

Intraperitoneal Administration of Monoclonal Antibody Against Pathologic Aβ42 Aggregates Alleviated Cognitive Deficits and Synaptic Lesions in APP/PS1 Mice.

Alzheimer's disease (AD) is the most common form of dementia, characterized by amyloid-β peptide (Aβ) aggregates, phosphorylated tau protein (p-tau), and progressive neurodegeneration. Amyloid-β peptide 42 (Aβ42) is considered an early trigger of AD pathogenesis. We have previously reported that Aβ N-terminus monoclonal antibody (mAb) A8 alleviated cognitive dysfunction and reduced the abundance of soluble Aβ in the brains of the senescence-accelerated mouse prone 8 (SAMP8) mouse model. To confirm the efficacy of mAb A8 in the double-transgenic APPswe/PS1ΔE9 (APP/PS1) mice, here we reported the related findings. The Morris water maze (MWM) data showed that the A8 treatment group had a shorter escape latency than the control groups in the place navigation test and the probe trial (p < 0.05). Moreover, immunohistochemistry showed decreased levels of both Aβ and p-tau in the brains of APP/PS1 mice. Regarding Aβ levels, western blot results showed that Aβ42 oligomer (p < 0.01) but not Aβ40 levels were diminished in brains of A8-treated APP/PS1 mice. Western blot results showed that phospho-tau (pSer231) (p < 0.01) but not tau levels were reduced in A8-treated mouse brains. Furthermore, transmission electron microscopy images indicated ultrastructural improvements, including an increased (p < 0.01) density of synapses and a reduction of abnormally enlarged mitochondria (p < 0.01), in the brains of A8-treated mice. Taken together, our data showed that mAb A8 is highly efficacious in APP/PS1 mice as a treatment for AD, and the underlying mechanism may target synaptic pathology by inhibiting the amyloid cascade.

A New Architecture based AR for Detection and Recognition of Objects and Text to Enhance Navigation of Visually Impaired People

Abstract Navigation in unfamiliar places is a big challenge for partially sighted and visually impaired people. Improving visual information on the location and content of objects such as drugs can help navigation in unfamiliar environments. There are several existing navigation solutions capable of helping these people. However, navigation solutions are rarely adopted and implemented in reality. In order to optimize the perception of digital information of objects from sensors and to naturally interact with the pervasive computing landscape, Augmented Reality (AR) equipment has to be seamlessly integrated into the user’s environment. For this purpose, we develop an architecture of text and objects recognition based on AR in order to assist partially sighted and visually impaired people. Such architecture makes navigation easier in the environment by helping users to find drugs and to verify the number of pills using speech. The proposed architecture uses context-aware mobile computing and shows great potential to integrate AR for object recognition through AR engines.

应用Morris水迷宫实验评估银屑病对小鼠模型认知功能的影响

Objective To evaluate the impact of psoriasis on spatial learning and memory abilities in mouse models by using Morris water maze. Methods Twenty healthy male C57BL/6J mice aged 10 months were randomly and equally divided into 2 groups: psoriasis group topically treated with imiquimod 5% cream on the back once a day for a week, and control group topically treated with vaseline once a day for a week. After successful establishment of mouse models, the Morris water maze (MWM) test was used to assess the learning and memory abilities in the mice in the 2 groups. Results In the place navigation experiment, the escape latency was significantly longer in the psoriasis group (38.24 ± 13.59 s) than in the control group (14.28 ± 3.80 s, t = 5.37, P 0.05) . Conclusion The spatial learning and memory abilities were impaired in the mouse model of psoriasis. Key words: Psoriasis; Cognition disorders; Learning disorders; Memory disorders; Disease models, animal; Morris water maze