Neural Imaging and Sensing are widely utilized in neuroscience research. The entire technical chain usually includes labeling, imaging, and image processing. Novel techniques are developed in rapid succession, and new applications follows. This presentation will focus on a bibliometrics study related to the three directions of the emerging neural imaging and sensing techniques. Based on Web of Science and Scopus, the hot topics are easily selected. We will highlight several typical techniques emerged in recent years, and discuss their advantages and specialized applications. Among those emerging techniques, a new crossdisciplinary field, brainsmatics, is growing up. Brainsmatics is the shorten term of Brain Spatial Informatics, which develops methods and tools for understanding brain based on brain spatial information. In neuroscience, scientific questions are focused and answered mainly in molecular, cellular, genetic, and electrophysiological levels, respectively. A full understanding of the brain calls for the integration of brain information in all levels. To combine all these different level data, the spatial information is the key reference. High resolution and precision positioning are two challenges in brainsmatics, while the image standard and brain-wide coordinate system definition are also important.

免疫学发展日新月异、内容更新快,教师必须及时在教学内容和教学方法上进行探索和创新."细胞与分子免疫学"是生命科学与技术学院研究生培养计划中的重要课程之一,我们通过三年教学实践,建立了包含生物学、生物医学工程和医学等领域学者的"学科交叉型"教学队伍,深化教学内容,采用全英语授课的中外研究生混合课堂教学模式,实施互动式与问题讨论式的教学方法,通过多模式教学效果评估,不仅提升了研究生综合学习能力,使得研究生变"学会"为"会学",而且促进了研究生创新思维的培养及实践能力的提升.

Summary form only given. Atmospheric-pressure room-temperature plasma jets are commonly used in plasma medicine, nanotechnology, as well as surface and materials processing. Most of the applications require room-temperature operation while completely avoiding the glow-to-arc transitions. To meet these requirements, the atmospheric plasma jets are usually sustained in noble gases. However, this is very challenging for the open-air operation. Moreover, the cross-sections of the plasma plumes are typically very small, which make large-area surface processing particularly difficult. One promising way to overcome this shortcoming is by using the plasma jet arrays. However, since the individual plasma plumes generated by the arrayed plasma jets are in most cases independent and do not merge in open air, it is very difficult to achieve uniform plasmas and surface treatment effects. In this paper, we demonstrate a homogenous cold air plasma glow with a large cross-section generated by a direct current power supply. There is no risk of glow-to-arc transitions, and the plasma glow appears uniform regardless of the gap between the nozzle and the surface being processed. Detailed studies show that both the position of the quartz tube and the gas flow rate affect the plasma characteristics. Further investigation indicates that the residual charges trapped on the inner surface of the quartz tube may be responsible for the generation of the air plasma plume with a large cross-section. Moreover, the spatially resolved optical emission spectroscopy reveals that the air plasma plume is uniform as it propagates out of the nozzle. The air plasma plume with remarkable improvement of the plasma uniformity is used to improve the bio-compatibility of a glass coverslip over a reasonably large area. This improvement is demonstrated by a much more uniform and effective attachment and proliferation of human embryonic kidney 293 (HEK 293) cells on the plasma-treated surface.

>Alzheimer’s disease(AD)was first described by German psychiatrist and neuropathologist Alois Alzheimer in 1906and was named after him.It is the most common form of dementia and highly prevalent.AD is predicted to affect one in 85 people globally by 2050.Well-known examples include Ronald Reagan,former US President,and Charles K.Kao,recipient of the 2009 Nobel Prize in Physics.

Stroke is a major health concern and an intensive research subject due that it is the major cause of death and the leading cause of disability worldwide. The past three decades of clinical disappointments in treating stroke must compel us to rethink our strategy. New effective protocol for stroke could greatly benefit from the advances in optical imaging technologies. This review focuses on the latest advance of applications of three optical imaging techniques in animal model of stroke, such as photoacoustic (PA) imaging, laser speckle contrast imaging (LSCI) and two-photon microscopy (TPM). The potential roles of those techniques in the future of stroke management are also discussed.

Gold nanoparticles（AuNPs） interact with light and have strong and tunable surface plasmon resonance,which can be detected using multiple imaging modalities.These provide an unique opportunity for their potential applications in optical imaging for early detection of cancer.In this review,we summarized nanoparticles targeting properties for cancer,plasmon optical properties of AuNPs,application of AuNPs for cancer optical imaging.Also discussed is the safety of AuNPs.

Because cerebral hypoperfusion brings damage to the brain, prevention of cerebrovascular diseases correlative to hypoperfusion by studying animal models makes great sense. Since complicated cerebrovascular adaptive changes in hypoperfusion could not be revealed only by cerebral blood flow (CBF) velocity imaging, we performed multi-parameter imaging by combining laser speckle imaging and functional photoacoustic microscopy. The changes in CBF, hemoglobin oxygen saturation (SO(2)), and total hemoglobin concentration (HbT) in single blood vessels of ipsilateral cortex were observed during transient cerebral hypoperfusion by ligating the unilateral common carotid artery in rats. CBF, SO(2), and HbT, respectively, decreased to 37 ± 3%, 71 ± 7.5%, and 92 ± 1.3% of baseline in 6 s immediately after occlusion, and then recovered to 77 ± 4.8%, 84 ± 8%, and 96 ± 2% of baseline in 60 s. These parameters presented the decrease with different degree and the following recovery over time after ligation, the recovery of SO(2) lagged behind those of CBF and HbT, which had the similar response. The results demonstrated that complete monitoring of both cerebral hemodynamic response and oxygen metabolic changes occurred at the earliest period of cerebral hypoperfusion was possible by using the two image modalities with high temporal and spatial resolution.

Cerebral blood flow (CBF) is critical for the maintenance of cerebral function by guaranteed constant oxygen and glucose supply to brain. Collateral channels (CCs) are recruited to provide alternatives to CBF to ischemic regions once the primary vessel is occluded during ischemic stroke. However, the knowledge of the relationship between dynamic evolution of collateral flow and the distribution of regional blood flow remains limited. In this study, laser speckle imaging was used to assess dynamic changes of CCs and regional blood flow in a rat cortex with permanent middle cerebral artery occlusion (MCAo). We found that CCs immediately provided blood flow to ischemic territories after MCAo. More importantly, there were three kinds of dynamic changes of CCs during acute stroke: persistent CC, impermanent CC, and transient CC, respectively, related to different distributions of regional blood flow. Although there was the possible occurrence of peri-infarct depolarization (PID) during ischemia, there was no obvious significance about the onset time and duration of CCs between rats with and without PID. These results suggest that the initial arising of CCs does not ensure their persistence, and that collateral flow could be varied with distribution of regional blood flow in acute ischemic stroke, which may facilitate the understanding of collateral recruitment and promote the development of collateral therapeutics in the future.

Stroke is a devastating disease. The changes in cerebral hemodynamics and oxygen metabolism associated with stroke play an important role in pathophysiology study. But the changes were difficult to describe with a single imaging modality. Here the changes in cerebral blood flow (CBF), cerebral blood volume (CBV), and oxygen saturation (SO2) were yielded with laser speckle imaging (LSI) and photoacoustic microscopy (PAM) during and after 3-h acute focal ischemic rats. These hemodynamic measures were further synthesized to deduce the changes in oxygen extraction fraction (OEF). The results indicate that all the hemodynamics except CBV had rapid declines within 40-min occlusion of middle cerebral artery (MCAO). CBV in arteries and veins first increased to the maximum value of 112.42±36.69% and 130.58±31.01% by 15 min MCAO; then all the hemodynamics had a persistent reduction with small fluctuations during the ischemic. When ischemia lasted for 3 h, CBF in arteries, veins decreased to 17±14.65%, 24.52±20.66%, respectively, CBV dropped to 62±18.56% and 59±18.48%. And the absolute SO2 decreased by 40.52±22.42% and 54.24±11.77%. After 180-min MCAO, the changes in hemodynamics and oxygen metabolism were also quantified. The study suggested that combining LSI and PAM provides an attractive approach for stroke detection in small animal studies.

Cortical spreading depression (CSD) is a pathophysiological phenomenon. There are sufficient evidences to prove that CSD plays an important role in some neurological disorders. However, exact mechanisms of its initiation and propagation are still unclear. Previous studies showed that glutamate receptors could be concerned with CSD, but those studies were mostly performed oriented to ionotropic glutamate receptors (iGluRs). There is relatively little report about effects of metabotropic glutamate receptors (mGluRs) on CSD. Here, we applied optical intrinsic signal imaging (OISI) combined with direct current (DC) potential recording to examine influences of some mGluRs antagonist (or agonist) on CSD propagation in rat's brain, to indirectly validate actions of some mGluRs on CSD. We found that N-acetyl-L-aspartyl-L-glutamate (NAAG, an agonist at mGluR3) inhibited the propagation of CSD, and the inhibition was gradually developed with time. However, 6-methyl-2-phenylethynyl-pyridine (MPEP, an antagonist of mGluR5) did not produce any significant alterations with the CSD propagation. Our findings suggest that mGluR3 could play an important role in the CSD propagation, but the activity of mGluR5 was comparatively weak. These findings can help to understand the propagation mechanism of CSD, and consider the therapy of some neurological diseases involved with CSD.

Objective To study the imaging features of multi-slice CT(MSCT) in the pulmonary embolism(PE),to explore the discrimination of disease which were similar with PE in feature,and to improve the level on the diagnosis and differentiation of PE.Methods 21 cases with PE(embolus consisting of tumor in 1 case) were examined with MSCT pulmonary angiography,the reformation images consisted of 10 mm slices,with 10 mm reconstruction intervals and 1.25 mm slices,with 0.625 mm reconstruction intervals.Then all the data were reconstructed by MPR,MIP,VR in the workstop.Results There were 20 cases of PE(pulmonary thromboembolism),18 cases of bilateral pulmonary arteries,and 2 cases of unilateral pulmonary arteries.131 branches of pulmonary embolism were identified,including 18 left and right distant pulmonary arteries,38 lobar arteries,50 segmental pulmonary arteries and 25 subeqmental pulmonary arteries.On post-contrast MSCTA,the direct sign was the filling defect in the PE branches at various degrees,and according to different shapes,there were four forms of filling defect: central filling defect(25 branches),eccentric filling defect(61 branches),embolism attached to the wall of host artery(25 branches),and total occlusion of the pulmonary arteries(20 branches).The indirect signs were as follows: dilated main pulmonary arteries,limited lung lack of blood,pulmonary embolism,pleural effusion,enlargement of right atrium and ventricle.Conclusion The imaging features of PE are varied,the displayed range is wide,bilateral PE are more than unilateral,and main pulmonary embolism are few.MSCT pulmonary angiography proves to be unique advantage for pulmonary embolism.This method can show the direct and indirect signs of PE clearly,and can provide sufficient diagnosis information of imaging.

Disturbances in glycaemia can significantly alter brain functions. Several brain-mapping techniques have been developed to characterize complex functional topography of the brain. This chapter introduces basic principles and instrumentations of two optical imaging techniques used for investigating cerebral hemodynamics: intrinsic optical signal imaging and laser speckle imaging. Especially, these two imaging techniques are used to study influences of acute hyperglycaemia on cerebral blood flow and spreading depression in rat cerebral cortex.

Bursts are electrical spikes firing with a high frequency, which are the most important property in synaptic plasticity and information processing in the central nervous system. However, bursts are difficult to identify because bursting activities or patterns vary with physiological conditions or external stimuli. In this paper, a simple method automatically to detect bursts in spike trains is described. This method auto-adaptively sets a parameter (mean inter-spike interval) according to intrinsic properties of the detected burst spike trains, without any arbitrary choices or any operator judgment. When the mean value of several successive inter-spike intervals is not larger than the parameter, a burst is identified. By this method, bursts can be automatically extracted from different bursting patterns of cultured neurons on multi-electrode arrays, as accurately as by visual inspection. Furthermore, significant changes of burst variables caused by electrical stimulus have been found in spontaneous activity of neuronal network. These suggest that the mean inter-spike interval method is robust for detecting changes in burst patterns and characteristics induced by environmental alterations.

In this paper, neurons were cultured on a substrate above a multielectrode array, so the changes of electrophysiological activity patterns during development of the neuronal network or in response to environmental perturbations were monitored. But the complexity of these spontaneous activity patterns is not well understood. In order to solve the problem, a comprehensive method (approximate entropy (ApEn) in combination with a "sliding window" over the data) is introduced to quantify the complexity of four spontaneous activity patterns (sporadic spikes, tonic spikes, pseudobursts, and typical bursts) in cultured hippocampal neuronal networks. The results show that the dynamic curves of ApEn illustrate vivid differences between the four patterns and the values of ApEn fall into different ranges. Among these patterns, the complexity of tonic spikes is the highest while that of pseudobursts is the lowest. This suggests that the proposed method is a valid procedure for tracking the dynamic variation in neuronal signals and can distinguish the different firing patterns of neuronal networks in terms of their complexity.

Techniques for functional brain imaging are critical to analyze the information processing of brain and to reveal the advanced functions in brain. These techniques are the hot topics of international research. Great success has been obtained with neuroimaging techniques in the fields of neuroscience research and clinical diagnosis. Existing brain functional imaging such as magnetic resonance imaging (fMRI),positron emission tomography (PET),electroencephalogram (EEG),magnetoencephalography (MEG) and so on,have been successfully used to study brain function. However,these methods have some limitations unavoidably in the temporal or spatial resolution at present. Comparatively,the optical imaging technologies of brain function show their unique charms. Laser speckle imaging (LSI) and intrinsic optical signals imaging (IOSI) stand out because they offer a superior combination of spatial sampling,spatial resolution and temporal resolution; on the other hand,they have no need to use exogenous contrast agents. Great developments also have been obtained in both techniques and applications of brain optical imaging,and they have become powerful tools for in vivo studying functional architecture and pathophysiology in cerebral cortex by monitoring hemodynamics. However,the two optical imaging techniques are confronted with some challenges.

The collateral circulation is crucial for the pathophysiology and outcome of acute cortical ischemia. Current understanding of collateral circulation still remains sparse, largely due to prior limitations of spatial or/and temporal resolution in methods to evaluate these diminutive redistributive routes of cerebral blood flow (CBF) especially in leptomeningeal anastomoses that connected cortical arteries. In the study, based on a mini-stroke model, laser speckle imaging with high spatiotemporal resolution was used to assess the dynamic evolution of the collateral circulation around a mini-ischemia in the rat cortex. We found that the blood flow and diameter in the intra-arterial anastomoses were enhanced immediately after the ligation of one branch of middle cerebral artery and recovered to baseline level as arterial recirculation was performed. Whereas the communicative flow-through of the posterior cerebral artery and the middle cerebral artery anastomoses was not significant enough to be determined. This is the evidence that intra-arterial anastomoses were the primary routes to restore blood flow into the ischemic territory during the acute phase of ischemia, and laser speckle imaging method was proven as a powerful tool to be potential for subserving further investigation of the collateral circulation.

Hyperglycemia and cortical spreading depression (CSD) are possible factors that worsen the outcome of ischemic stroke, and it is probable that there is a longterm cooperative effect of hyperglycemia and CSD on cerebral blood flow (CBF). Long-lasting and full-field observation of changes in CBF following CSD in vivo during acute hyperglycemia in rats might show whether this is the case. Here, we utilized laser speckle imaging to study influences of acute hyperglycemia on CBF at the level of individual vascular compartments for 3 h in normal rats and those with CSD. It is shown that there are extensive increases of CBF at the arteriole and parenchyma over the normal rat cortex during acute hyperglycemia, whereas there is no significant change in CBF at the venule. We also find that, at all vascular compartments, after the glucose administration there is a stepwise reduction of CBF following CSD, but after saline injection CBF following CSD is close to the baseline. Our results indicate that acute hyperglycemia could aggravate the severity of decrease in CBF following CSD, suggesting possible mechanisms by which hyperglycemia exacerbates cerebral damage after ischemic stroke.

Mini-ischemia localized into a specific brain area has promoted understanding of the mechanisms underlying brain recovery in stroke. However, the conventional mini-stroke model adopted permanent arterial ligations but lacked controllable reperfusion, which is crucial for the outcome of delayed functional recovery. In this study, we devised a new rat mini-stroke model in which the vascular ligations can be easily reversed to induce targeted reperfusion. Specifically, a flexible ring was incorporated into the conventional small arterial ligations to tighten the ligating loops and facilitate cutting the ligatures for sufficient reperfusion afterwards. The distribution of cerebral blood flow was explored directly through a cranial window using laser speckle contrast imaging. A distinct ischemic core, which well fits the profile of the ligated ring, was bordered by a penumbral zone and then together surrounded by nonischemic tissue immediately after the arterial ligations involving the ring. After cutting the ligatures, post-recanalization hyperperfusion occurred in the previous ischemic core and to a greater extent at 24 h after reperfusion. In contrast, recirculation of common carotid artery in the conventional mini-stroke model hardly altered hypoperfusion status within the ischemic core. Evidence from two kinds of control groups indicated that the ring might produce a compression effect on the underlying cortex and then contribute to the more highly localized infarct that was identified by triphenyltetrazolium chloride staining. Our data suggest that this model provides opportunities for investigating the neurovascular dynamics in acute stroke and rehabilitation, especially with emerging optical imaging techniques.

The changes of intrinsic optical signals (IOS) are one of the important parameters of spreading depression (SD). The relationship between cerebral blood flow (CBF) and IOS can provide useful information for understanding the role of SD in neurological disorders. Here, we combined laser speckle imaging (LSI), intrinsic optical signal imaging (IOSI), and electrophysiological recording techniques to study the effect of CBF before the occurrence of SD on the spatiotemporal characteristics of IOS related to SD in a ministroke model. Four kinds of temporal pattern of changes in IOS were observed at cortical locations with different level of the CBF before the occurrence of SD. The results indicate that in the surrounding of micro-infarcts, SD-associated IOS vary as a function of blood flow rate, suggesting that the characteristics of IOS during SD might reflect blood flow rates.

Laser speckle temporal contrast analysis (LSTCA) was used to image the cerebral blood flow (CBF) of ischemic area in reperfused mini-stroke model in rats. Focal cortical ischemia in male Sprague-Dawley rats (n=20) was induced by deliberate ligation of multiple branches of the middle cerebral artery (MCA) together with a nylon ring and the dura. LSTCA was used to monitor the spatio-temporal characteristics of cerebral blood flow dynamics in the rat somatosensory cortex in the ischemic and reperfused stages. The infarction volume was measured by 2, 3, 5-triphenyltetrazolium chloride (TTC) staining 24 hours after reperfusion. The distribution of changes in cerebral blood flow which outlined by the laser speckle imaging represented the relative CBF gradient (21.98 +/- 1.96%, 67.2 +/- 1.67 %, 107.24 +/- 4.71 % of the baseline) from ischemic core, penumbra zone to normal tissue immediately after cortical ischemia, in which a central ischemic core had little or no perfusion surrounded by a penumbral region with reduced perfusion, in addition, we had shown the existence of a surrounding region of hyperemic tissue; Thereafter a post-recanalization hyperperfusion occurred in the same infarct core since 24 hours after reperfusion (242.62 +/- 18.52 % of the baseline). Histology of the ischemic regions at 24 hours after reperfusion revealed small focal infarcts that were typically 3 similar to 4 mm in diameter, approximately equal to the nylon ring in size and position and essentially accordant with the spatial distribution of the ischemic cortex with below 30% residual CBF of the pre-ischemic baseline. It was demonstrated that this technique of LSTCA was easy to implement and availably used to image the spatial and temporal evolution of CBF changes with high resolution in rat reperfused mini-stroke model.