Astrocytic Ca2+ transients are essential for astrocyte integration into neural circuits. These Ca2+ transients are primarily sequestered in subcellular domains, including primary branches, branchlets and leaflets, and endfeet. In previous studies, it suggests that aging causes functional defects in astrocytes. Until now, it was unclear whether and how aging affects astrocytic Ca2+ transients at subcellular domains. In this study, we combined a genetically encoded Ca2+ sensor (GCaMP6f) and in vivo two-photon Ca2+ imaging to determine changes in Ca2+ transients within astrocytic subcellular domains during brain aging. We showed that aging increased Ca2+ transients in astrocytic primary branches, higher-order branchlets, and terminal leaflets. However, Ca2+ transients decreased within astrocytic endfeet during brain aging, which could be caused by the decreased expressions of Aquaporin-4 (AQP4). In addition, aging-induced changes of Ca2+ transient types were heterogeneous within astrocytic subcellular domains. These results demonstrate that the astrocytic Ca2+ transients within subcellular domains are affected by aging differently. This finding contributes to a better understanding of the physiological role of astrocytes in aging-induced neural circuit degeneration.
Intelligent mulberry fields is a way to apply computer, sensor technology and intelligent control technology to mulberry planting process based on Internet of things technology. Its core is the use of mulberry data sensing technology, as far as possible to reduce or even replace manual, in the Internet of things through the sensor to transmit information to the cloud platform, to achieve semi-automatic. In this paper, aiming at the application of Internet of Things in mulberry field management, in order to save labor costs, standardize and intelligent management, and promote agricultural development, the traditional planting methods of mulberry field are combined with modern scientific technology to discuss the research of intelligent mulberry field. Firstly, the concept of intelligent mulberry fields and Internet of things is introduced. Secondly, according to the current construction status of intelligent mulberry garden, the role of Internet of things in mulberry fields agriculture is explained. In view of mulberry management, the application of Internet of things technology in intelligent mulberry fields is discussed in detail. Finally, the future development trend of intelligent mulberry fields is analyzed and prospected.
Laryngeal lesions can cause great inconvenience to patients. Early diagnosis and corresponding treatments are critical to the survival of patients. However, the diagnosis and precise removal of tumors remain a challenge under the use of a white light laryngoscope. In this work, an integrated, multifunctional laryngoscope was designed and tested for the imaging evaluation and precision laser surgery for laryngeal tissue. This integrated diagnostic and therapeutic endoscopic system included two imaging modes (i.e., optical coherence tomography and white light endoscopy) and a laser ablation treatment mode. The endoscope had a common-path design to ensure that the same position could be imaged and treated simultaneously. The ex vivo porcine larynx experimental results showed that the system imaging modes could simultaneously acquire both superficial and cross-sectional images of the sample tissue, and the ablation treatment could be performed under imaging guidance. This multifunctional laryngoscope has great potential for the early diagnosis of and accurate laser ablation surgery for laryngeal tumors.
The outbreak caused by SARS-CoV-2 has received extensive worldwide attention. As the main protease (Mpro) in SARS-CoV-2 has no human homologues, it is feasible to reduce the possibility of targeting the host protein by accidental drugs. Thus, Mpro has been an attractive target of efficient drug design for anti-SARS-CoV-2 treatment. In this work, multiple replica molecular dynamics (MRMD) simulations, principal component analysis (PCA), free energy landscapes (FELs), and the molecular mechanics-generalized Born surface area (MM-GBSA) method were integrated together to decipher the binding mechanism of four inhibitors masitinib, O6K, FJC and GQU to Mpro. The results indicate that the binding of four inhibitors clearly affects the structural flexibility and internal dynamics of Mpro along with dihedral angle changes of key residues. The analysis of FELs unveils that the stability in the relative orientation and geometric position of inhibitors to Mpro is favorable for inhibitor binding. Residue-based free energy decomposition reveals that the inhibitor-Mpro interaction networks involving hydrogen bonding interactions and hydrophobic interactions provide significant information for the design of potent inhibitors against Mpro. The hot spot residues including H41, M49, F140, N142, G143, C145, H163, H164, M165, E166 and Q189 identified by computational alanine scanning are considered as reliable targets of clinically available inhibitors inhibiting the activities of Mpro.
Automatic sleep stage classification plays an essential role in sleep quality measurement and sleep disorder diagnosis. Although many approaches have been developed, most use only single-channel electroencephalogram signals for classification. Polysomnography (PSG) provides multiple channels of signal recording, enabling the use of the appropriate method to extract and integrate the information from different channels to achieve higher sleep staging performance. We present a transformer encoder-based model, MultiChannelSleepNet, for automatic sleep stage classification with multichannel PSG data, whose architecture is implemented based on the transformer encoder for single-channel feature extraction and multichannel feature fusion. In a single-channel feature extraction block, transformer encoders extract features from time-frequency images of each channel independently. Based on our integration strategy, the feature maps extracted from each channel are fused in the multichannel feature fusion block. Another set of transformer encoders further capture joint features, and a residual connection preserves the original information from each channel in this block. Experimental results on three publicly available datasets demonstrate that our method achieves higher classification performance than state-of-the-art techniques. MultiChannelSleepNet is an efficient method to extract and integrate the information from multichannel PSG data, which facilitates precision sleep staging in clinical applications.
Swept source optical coherence tomography (SSOCT) is an attractive biological imaging technology due to its advantages of simple setup and high imaging speed. As the light intensity attenuated rapidly in high scattering biological tissues, the contrast of OCT image will drop with depth. In this paper a new method was introduced to compensate the attenuation of imaging contrast in SSOCT. The interference signal was divided into two channels of analog to digital converter (ADC) with a splitting ratio of 1:5. The higher level signal in one channel was used to reconstruct deeper structure of tissue and the lower level signal in the other channel was used to reconstruct surface structure of tissue. Lowfrequency signals in one channel were filtered by a high pass filter and then combined with the signal in the other channel to obtain a high contrast image in both surface and deep area of tissue. Human finger and porcine airway imaging obtained with the system show that the contrast of SSOCT images can be improved in deeper region of tissue.
Urination, a vital and conserved process of emptying urine from the urinary bladder in mammals, requires precise coordination between the bladder and external urethra sphincter (EUS) that is tightly controlled by a complex neural network. However, the specific subpopulation of neurons that accounts for such coordination remains unidentified, limiting the development of target-specific therapies for certain urination disorders, e.g. detrusor-sphincter dyssynergia. Here, we find that cells expressing estrogen receptor 1 (ESR1 + ) in the pontine micturition center (PMC) initiate voiding when activated and suspend ongoing voiding when suppressed, each at 100% reliability, respectively. Transection of either the pelvic or the pudendal nerve does not impair PMC ESR1+ control of the downstream target through the other nerve at all. Anatomically, PMC ESR1+ cells possess two subpopulations projecting to either the pelvic or pudendal nerve and a third, dual-projecting subpopulation, locking in the coordination of bladder contraction and sphincter relaxation in a rigid temporal order. We identify a cell type in the brainstem that controls the bladder-urethra coordination for urination.