Phospho-tau accumulation and adult hippocampal neurogenesis (AHN) impairment both contribute importantly to the cognitive decline in Alzheimer’s disease (AD), but whether and how tau dysregulates AHN ...in AD remain poorly understood. Here, we found a prominent accumulation of phosphorylated tau in GABAergic interneurons in the dentate gyrus (DG) of AD patients and mice. Specific overexpression of human tau (hTau) in mice DG interneurons induced AHN deficits but increased neural stem cell-derived astrogliosis, associating with a downregulation of GABA and hyperactivation of neighboring excitatory neurons. Chemogenetic inhibition of excitatory neurons or pharmacologically strengthening GABAergic tempos rescued the tau-induced AHN deficits and improved contextual cognition. These findings evidenced that intracellular accumulation of tau in GABAergic interneurons impairs AHN by suppressing GABAergic transmission and disinhibiting neural circuits within the neurogenic niche, suggesting a potential of GABAergic potentiators for pro-neurogenic or cell therapies of AD.
Display omitted
•Phospho-tau is accumulated in DG GABAergic interneurons of AD patients and mice•Interneuron overexpressing human tau impairs adult hippocampal neurogenesis•Tau accumulation reduces GABA, disinhibits local circuits, and promotes astrogliosis•THIP, a δ-GABAAR agonist, improves neurogenesis and cognition in AD mice
Impaired adult hippocampal neurogenesis contributes to the cognitive decline in Alzheimer’s disease. Zheng et al. report that phospho-tau accumulation in dentate gyrus GABAergic interneurons disrupts adult hippocampal neurogenesis and increased astrogliosis. Importantly, strengthening GABAergic signaling can rescue neurogenesis and improve cognitive functions in mouse models of Alzheimer’s disease.
•Development of EC for an automatic on-line inspection of steel balls surface.•A FAECS is proposed to inspect the whole ball surface and sub-surface with high accuracy.•Simplify the mechanism of ...steel ball surface unfolding.
In order to perform the rapid and efficient automatic on-line inspection of the surface quality of steel ball, a new spherical deployment method based on flexible array eddy current sensor (FAECS) is proposed. Full unfolding of the steel ball surface can be performed by combining the flexible array eddy current sensor with the one-dimensional orbital deployment. The inspection coil of array eddy current sensor is fabricated on flexible printed circuit board (FPCB), which is bent into a semicircle to fix on the top of one-dimensional track. When the steel ball rolls on the one-dimensional track, complete inspection of steel ball surface can be performed by the flexible array eddy current sensor. In this method, one-dimensional mechanical motion is used instead of the traditional two-dimensional deployment motion, which reduces the complexity and cost of deployment structure. Three typical defects include linear cracks (0.12 mm width × 0.5 mm depth), cross cracks (0.06 mm width × 0.9 mm depth) and arc cracks (0.05 mm width × 0.1 mm depth) are measured in the experiment to verify the effectiveness of the inspection system. Subsequently, same batch of steel balls are tested at speed of 4 pcs/s, results show that the inspection accuracy of surface defect of steel balls is 95.52%, and the false inspection rate is less than 0.7%, which proves this method efficiency.
Pain involves an intrinsically dynamic connectome characterized by fluctuating spontaneous brain activity and continuous neuroplastic changes of relevant circuits. Activity in the hippocampus-medial ...prefrontal cortex (mPFC) pathway has been suggested to correlate with spontaneous pain and pain chronicity, but causal evidence is lacking. Here we combine longitudinal in vivo electrophysiological recording with behavioral testing and show that persistent spontaneous pain disrupts ventral hippocampal CA1-infralimbic cortex (vCA1-IL) connectivity and hippocampal modulation of IL neuronal activity in rats with peripheral inflammation. Chemo- and optogenetic rescue of vCA1-IL dysfunction relieves spontaneous pain. Circuit-specific overexpression of brain-derived neurotrophic factor (BDNF) in vCA1-IL reverses electrophysiological changes, relieves spontaneous pain, and accelerates overall recovery from inflammatory pain. Our work identifies a neural pathway that specifically correlates with spontaneous pain and supports the significance of using a circuit dynamics-based strategy for more comprehensive understanding of circuitry mechanisms underlying chronic pain.
Display omitted
•Ventral hippocampal CA1-infralimbic cortex (vCA1-IL) connectivity is involved in pain•Persistent spontaneous pain in rats with inflammation disrupts vCA1-IL connectivity•Activating vCA1-IL alleviates spontaneous pain and promotes overall pain recovery•BDNF expression correlates with behavior and activity changes in spontaneous pain
Ma et al. show that persistent spontaneous pain disrupts ventral hippocampal CA1-infralimbic cortex (vCA1-IL) connectivity in rats with peripheral inflammation. Genetic rescue of vCA1-IL dysfunction relieves spontaneous pain and accelerates overall pain recovery. This work identifies a neural pathway that specifically correlates with spontaneous pain.
Deep brain stimulation (DBS) is a promising therapy for treatment-resistant depression, while mechanisms underlying its therapeutic effects remain poorly defined. Increasing evidence has revealed an ...intimate association between the lateral habenula (LHb) and major depression, and suggests that the LHb might be an effective target of DBS therapy for depression. Here, we found that DBS in the LHb effectively decreased depression-like behaviors in rats experienced with chronic unpredictable mild stress (CUMS), a well-accepted paradigm for modeling depression in rodents. In vivo electrophysiological recording unveiled that CUMS increased neuronal burst firing, as well as the proportion of neurons showing hyperactivity to aversive stimuli in the LHb. Nevertheless, DBS downregulated local field potential power, reversed the CUMS-induced increase of LHb burst firing and neuronal hyperactivity to aversive stimuli, and decreased the coherence between LHb and ventral tegmental area (VTA). Our results demonstrate that DBS in the LHb exerts antidepressant-like effects and reverses local neural hyperactivity, supporting the LHb as a target of DBS therapy for depression.
•Deep brain stimulation (DBS) in the lateral habenula (LHb) alleviates depression-like behaviors.•DBS in the LHb reverses the increased LHb burst firing and neuronal hyperactivity to aversive stimuli under depression.•DBS in the LHb decreases the coherence between the LHb and ventral tegmental area.
Chronic pain is one of the most significant medical problems throughout the world. Recent evidence has confirmed the hippocampus as an active modulator of pain chronicity, but the underlying ...mechanisms remain unclear. Using in vivo electrophysiology, we identify a neural ensemble in the ventral hippocampal CA1 (vCA1) that shows inhibitory responses to noxious but not innocuous stimuli. Following peripheral inflammation, this ensemble becomes responsive to innocuous stimuli, representing hypersensitivity. Mimicking the inhibition of vCA1 neurons using chemogenetics induces chronic pain-like behaviors in naive mice, whereas activating vCA1 neurons in mice with peripheral inflammation results in a reduction of pain-related behaviors. Pathway-specific manipulation of vCA1 projections to basolateral amygdala (BLA) and infralimbic cortex (IL) shows that these pathways are differentially involved in pain modulation at different temporal stages of chronic inflammatory pain. These results confirm a crucial role of the vCA1 and its circuits in modulating the development of chronic pain.
Display omitted
•A distinct subset of neurons in vCA1 shows inhibitory responses to nociceptive stimuli•vCA1 noxious-inhibited neurons respond to innocuous stimuli during pathological pain•The suppressed activity of vCA1 causally contributes to pain behaviors in chronic pain•vCA1-IL/BLA pathways are differentially involved in chronic inflammatory pain
Shao et al. reveal a group of neurons in ventral CA1 (vCA1) that show inhibitory responses to noxious stimuli but respond to innocuous stimuli during peripheral inflammation. The inhibitory activity in vCA1 causally contributes to pain behaviors, suggesting a crucial role of the vCA1 in chronic pain.
Abstract
Spontaneous pain occurring without apparent external stimuli, is a significant complaint of individuals with chronic pain whose mechanisms, somewhat surprisingly, remain poorly understood. ...Over the past decades, neuroimaging studies start to reveal brain activities accompanying spontaneous pain. Meanwhile, a variety of animal models and behavioral tests have been established, including non-reflexive tests and free-choice tests, which have been shown to be effective in assessing spontaneous pain. For the spontaneous pain mechanisms, multiple lines of research mainly focus on three aspects: (1) sensitization of peripheral nociceptor receptors and ion channels, (2) spontaneous neuronal firing and abnormal activity patterns at the dorsal root ganglion and spinal cord level, (3) functional and structural alterations in the brain, particularly the limbic system and the medial pain pathway. Despite accumulating evidence revealing distinct neuronal mechanisms from evoked pain, we are still far from full understanding of spontaneous pain, leaving a big gap between bench and bedside for chronic pain treatment. A better understanding of the neural processes in chronic pain, with specific linkage as to which anatomical structures and molecules related to spontaneous pain perception and comorbidities, will greatly improve our ability to develop novel therapeutics.
With the emergence and popularity of iris biometrics, there are increasing concerns regarding the feasibility of iris authentication systems and their corresponding variability reduction methods. The ...former issues are typically addressed by optimizing key factors, such as iris size, image quality and acquisition wavelength. As for the latter, introducing error correction codes to reduce intra-user variability in the enrolled identifiers becomes novelly promising. This paper proposes a conventional iris authentication system and a hardware-friendly QC-LDPC error correction code scheme on a microprocessor-FPGA platform. Different QC-LDPC codes in IEEE 802.16e were analyzed and selected. Suitable codes were applied, followed by the evaluation experiments. The proposed design achieves a competitive result with up to 0.20% EER and 0.50% ZeroFAR on the CASIA-IrisV4-Syn database. Cryptographic keys with lengths of up to 288 bits can also be generated and recovered. Such a device can be potentially used for applications such as an access control system in high-security areas, identity verification at the borders, biometric cryptography and related authentication scenarios.
In urban environments, semantic segmentation using computer vision plays a pivotal role in understanding and interpreting the diverse elements within urban imagery. The Cityscapes dataset, widely ...used for semantic segmentation in urban scenes, predominantly features urban elements like buildings and vehicles but lacks aquatic elements. Recognizing this limitation, our study introduces a method to enhance the Cityscapes dataset by incorporating aquatic classes, crucial for a comprehensive understanding of coastal urban environments. To achieve this, we employ a dual-model approach using two advanced neural networks. The first network is trained on the standard Cityscapes dataset, while the second focuses on aquatic scenes. We adeptly integrate aquatic features from the marine-focused model into the Cityscapes imagery. This integration is carefully executed to ensure a seamless blend of urban and aquatic elements, thereby creating an enriched dataset that reflects the realities of coastal cities more accurately. Our method is evaluated by comparing the enhanced Cityscapes model with the original on a set of diverse urban images, including aquatic views. The results demonstrate that our approach effectively maintains the high segmentation accuracy of the original Cityscapes dataset for urban elements while successfully integrating marine features. Importantly, this is achieved without necessitating additional training, which is a significant advantage in terms of resource efficiency.
The emergence of the AI era signifies a shift in the future landscape of global communication networks, wherein robots are expected to play a more prominent role compared to humans. The establishment ...of a novel paradigm for the development of next-generation 6G communication is of utmost importance for semantics task-oriented empowered communications. The goal of semantic communication lies in the integration of collaborative efforts between the intelligence of the transmission source and the joint design of source coding and channel coding. This characteristic represents a significant benefit of joint source-channel coding (JSCC), as it enables the generation of source alphabets with diverse lengths and achieves a code rate of unity. Therefore, we leverage not only quasi-cyclic (QC) characteristics to facilitate the utilization of flexible structural hardware design but also Unequal Error Protection (UEP) to ensure the recovery of semantic importance. In this study, the feasibility of using a semantic encoder/decoder that is aware of UEP can be explored based on the existing JSCC system. This approach is aimed at protecting the significance of semantic task-oriented information. Additionally, the deployment of a JSCC system can be facilitated by employing QC-Low-Density Parity-Check (LDPC) codes on a reconfigurable device. The QC-LDPC layered decoding technique, which has been specifically optimized for hardware parallelism and tailored for channel decoding applications, can be suitably adapted to accommodate the JSCC system. The performance of the proposed system is evaluated by conducting BER measurements using both floating-point and 6-bit quantization. This is done to assess the extent of performance deterioration in a fair manner. The fixed-point system is synthesized and subsequently used as a semantic feature transmission and reception system across a noisy channel, with the aim of presenting a prototype for semantic communications. This study concludes with some insights and potential research avenues for the JSCC prototype in the context of future communication.
Biofilms formed on urinary catheters remain a major headache in the modern healthcare system. Among the various kinds of biocide-releasing urinary catheters that have been developed to prevent ...biofilm formation, Ag nanoparticles (AgNPs)-coated catheters are of great promising potential. However, the deposition of AgNPs on the surface of catheters suffers from several inherent shortcomings, such as damage to the urethral mucosa, uncontrollable Ag ion kinetics, and unexpected systematic toxicity. Here, AgNPs-decorated amphiphilic carbonaceous particles (ACPs@AgNPs) with commendable dispersity in solvents of different polarities and broad-spectrum antibacterial activity are first prepared. The resulting ACPs@AgNPs exert good compatibility with silicone rubber, which enables the easy fabrication of urinary catheters using a laboratory-made mold. Therefore, ACPs@AgNPs not only endow the urinary catheter with forceful biocidal activity but also improve its mechanical properties and surface wettability. Hence, the designed urinary catheter possesses excellent capacity to resist bacterial adhesion and biofilm formation both in vitro and in an in vivo rabbit model. Specifically, a long-term antibacterial study highlights its sustainable antibacterial activity. Of note, no obvious toxicity or inflammation in rabbits was triggered by the designed urinary catheter in vivo. Overall, the hybrid urinary catheter may serve as a promising biocide-releasing urinary catheter for antibacterial and antibiofilm applications.
PDF
