Objective To analyze the activities of cultured neuronal network in response to electric pulses stimuli with different intervals. Method Pairs of electric pulses with different intervals were added to rat hippocampal neurons cultured on multi-electrode arrays (MEA) substrate. Result The second response duration of the network increased with the decrease of the interval between two pulses. It was typical that the second duration after pulses with 10 ms interval increased greatly and it could be divided into two stages, i.e. quick response (within 10 ms) and slow response (near or beyond 100 ms). However, following pulses with 100 ms interval,there is practically no relation between the two responses; the second response duration was shorter and the number of spikes was fewer and their amplitudes were lower, which is similar to the result of single electric pulse stimulus. Conclusion The activity of cultured neuronal network was different in response to different electric stimulation patterns. Compared with spontaneous firing, the activity of the network is potentiated or depressed respectively after different stimulations.

Objective To validate near-infrared cerebral topography (NCT) as a practical toolin tracing the regional hemodynamic changes during normal ischemic stroke model of rat. Method Middle cerebral artery occlusion (MCAO) and photosensitizer induced intracranial infarction model of rat were established. The geometric shape and infarction area were measured by NCT, functional magnetic resonance imaging (fMRI), and TTC stained anatomical imaging techniques. Result In photosensitizer induced infarction model, the correlation between anatomical infarct area and NCT image area for infarct focus were r= 0.897 for 24 h group (P<0.05) and r=0.906 for 2 months group (P<0.01),respectively. The correlation between anatomical infarction area and NCT image area for infarct focus were r=0.820 for normothermia group (P<0.05) and r= 0.851 for hypothermia group (P<0.05), respectively. The correlation between fMRI and NCT image area for infarction focus were r= 0.874 for normothermia group (P<0.05) and r= 0.782 for hypothermia group (P<0.05),respectively. Conclusion Measurement with NCT for infarction focus matched well with fMRI and anatomic sample in rats. NCT technique might be a practical tool for short-term prediction of stroke and the rehabilitation after stroke in real time.

Objective To explore the role of the prefrontal cortex in semantic encoding of unrelated word pairs by using functional near-infrared spectroscopy (fNIRS). Method Forty-eight subjects were presented unrelated pairs of Chinese words under both the nonsemantic and semantic encoding conditions. Under the nonsemantic condition, subjects judged whether the two words had similar orthographic structures; under the semantic condition, they generated a sentence involving the presented word pairs. The changes of regional blood volume associated with the cognitive tasks were measured by using fNIRS equipment which was a continuous optical imager. Result The regions that corresponded to the prefrontal regions showed greater activation under semantic than nonsemantic condition in both left and right hemispheres, although the extent of the activation was larger in the left than right prefrontal regions. This result was consistent with other neuroimaging studies on unrelated word pairs processing, but did not conform to the strict interpretations of the hemispheric encoding/retrieval asymmetry model (HERA). Conclusion This study suggests that material specificity is one of the important factors to influence hemispheric asymmetry in memory encoding. When associations between items are required, right prefrontal regions participate in the encoding processing as well. It also indicates that fNIRS imaging is a viable method of investigating higher level cognitive processing such as memory.

Objective To investigate the left prefrontal lobe activation during semantic and non-semantic encoding tasks with functional near-infrared imaging (fNIRI) technique. Method 22 healthy subjects were assigned semantic encoding and non-semantic encoding tasks. During semantic encoding tasks, subjects were asked to make a meaningful sentence including two unrelated Chinese word pairs, while during non-semantic encoding task they were asked to judge whether the two Chinese word pairs had the same morphological structure or not. Light intensity of two wavelengths (760 nm and 850 nm) diffused through skull and left prefrontal lobe were real-time recorded and used to reconstruct the brain activation image during the experiment. Result With the fNIRI, significant activations were observed in the left inferior prefrontal cortex (Brodmann' areas 45 and 47) during the two tasks, but the evoked activations were more significant for semantic than non-semantic task. These observations were consistent with the results reported by others with functional megnetic resonance imaging(fMRI) and positron-emission tomographyPET.Conclusion The results suggest that fNIRI provides an important, non-invasive way to map the prefrontal activation during cognitive tasks.

Objective: To evaluate the accuracy of automated fluorescence microscopic imaging and computer-aided diagnosis system (AFMICADS) in the auxiliary diagnosis of superficial cutaneous fungal infections. Methods: Totally, 106 outpatients and inpatients with suspected superficial fungal infections were enrolled from clinical departments of Union Hospital, Tongji Medical College, Huazhong University of Science and Technology between July 2018 and September 2018. A total of 126 specimens were collected, including 83 skin scales and 43 nail parings. Each specimen was divided into 3 groups to be examined by conventional fungal microscopy, culture with modified Sabouraud dextrose agar and fluorescence microscopy (artificial fluorescence microscopy and AFMICADS-based fluorescence microscopy) respectively. A positive result was defined as that conventional fungal microscopy and/or fungal culture was positive. Consistency rate, sensitivity and specificity of the 3 microscopic methods were calculated. Statistical analysis was carried out with SPSS 10.0 software by using McNemar test and Kappa test for analyzing difference in the positive rate, as well as consistency, between the 3 microscopic methods and the positive standard, and by using efficiency test for comparing the consistency rate among the 3 microscopic methods. Results: Of 126 specimens, 124 (98.4%) were positive for artificial fluorescence microscopy, and 123 (97.6%) for AFMICADS-based fluorescence microscopy. Both positive rates of the above 2 microscopic methods were significantly higher than the positive rate of the positive standard (77.8%, both P < 0.001) . The sensitivity, specificity and consistency rate of AFMICADS-based fluorescence microscopy were 100%, 10.7% and 80.2% respectively, and those of artificial fluorescence microscopy were 100%, 7.1% and 79.4% respectively. Additionally, no significant difference in the consistency was observed between the AFMICADS-based and artificial fluorescence microscopy (P > 0.05) . Conclusion The accuracy of AFMICADS-based fluorescence microscopy in the diagnosis of superficial cutaneous fungal infections is similar to that of artificial fluorescence microscopy.

The orbitofrontal cortex (OFC) is involved in diverse brain functions via its extensive projections to multiple target regions. There is a growing understanding of the overall outputs of the OFC at the population level, but reports of the projection patterns of individual OFC neurons across different cortical layers remain rare. Here, by combining neuronal sparse and bright labeling with a whole-brain florescence imaging system (fMOST), we obtained an uninterrupted three-dimensional whole-brain dataset and achieved the full morphological reconstruction of 25 OFC pyramidal neurons. We compared the whole-brain projection targets of these individual OFC neurons in different cortical layers as well as in the same cortical layer. We found cortical layer-dependent projections characterized by divergent patterns for information delivery. Our study not only provides a structural basis for understanding the principles of laminar organizations in the OFC, but also provides clues for future functional and behavioral studies on OFC pyramidal neurons.