Different coding characteristics between flight and freezing in dorsal periaqueductal gray of mice during exposure to innate threats.

BACKGROUND: Flight and freezing are two vital defensive behaviors that mice display to avoid natural enemies. When they are exposed to innate threats, visual cues are processed and transmitted by the visual system into the emotional nuclei and finally transmitted to the periaqueductal gray (PAG) to induce defensive behaviors. However, how the dorsal PAG (dPAG) encodes the two defensive behaviors is unclear. METHODS: Multi-array electrodes were implanted in the dPAG nuclei of C57BL/6 mice. Two kinds of visual stimuli (looming and sweeping) were used to induce defensive behaviors in mice. Neural signals under different defense behaviors were recorded, and the encoding characteristics of the two behaviors were extracted and analyzed from spike firing and frequency oscillations. Finally, synchronization of neural activity during the defense process was analyzed. RESULTS: The neural activity between flight and freezing behaviors showed different firing patterns, and the differences in the inter-spike interval distribution were mainly reflected in the 2-10 ms period. The frequency band activities under both defensive behaviors were concentrated in the theta band; the active frequency of flight was ~8 to 10 Hz, whereas that of freezing behavior was ~6 to 8 Hz. The network connection density under both defense behaviors was significantly higher than the period before and after defensive behavior occurred, indicating that there was a high synchronization of neural activity during the defense process. CONCLUSIONS: The dPAG nuclei of mice have different coding features between flight and freezing behaviors; during strong looming stimulation, fast neuro-instinctive decision making is required while encountering weak sweeping stimulation, and computable planning late behavior is predicted in the early stage. The frequency band activities under both defensive behaviors were concentrated in the theta band. There was a high synchronization of neural activity during the defense process, which may be a key factor triggering different defensive behaviors.

Noise-induced collective dynamics in the small-world network of photosensitive neurons.

Photosensitive neurons can capture and convert external optical signals, and then realize the encoding signal. It is confirmed that a variety of firing modes could be induced under optical stimuli. As a result, it is interesting to explore the mode transitions of collective dynamics in the photosensitive neuron network under external stimuli. In this work, the collective dynamics of photosensitive neurons in a small-world network with non-synaptic coupling will be discussed with spatial diversity of noise and uniform noise applied on, respectively. The results prove that a variety of different collective electrical activities could be induced under different conditions. Under spatial diversity of noise applied on, a chimera state could be observed in the evolution, and steady cluster synchronization could be detected in the end; even the nodes in each cluster depend on the degree of each node. Under uniform noise applied on, the complete synchronization window could be observed alternately in the transient process, and steady complete synchronization could be detected finally. The potential mechanism is that continuous energy is pumped in the phototubes, and energy exchange and balance between neurons to form the resonance synchronization in the network with different noise applied on. Furthermore, it is confirmed that the evolution of collective dynamical behaviors in the network depends on the external stimuli on each node. Moreover, the bifurcation analysis for the single neuron model is calculated, and the results confirm that the electrical activities of single neuron are sensitive to different kinds of noise.

The Superior Colliculus/Lateral Posterior Thalamic Nuclei in Mice Rapidly Transmit Fear Visual Information Through the Theta Frequency Band.

Animals perceive threat information mainly from vision, and the subcortical visual pathway plays a critical role in the rapid processing of fear visual information. The superior colliculus (SC) and lateral posterior (LP) nuclei of the thalamus are key components of the subcortical visual pathway; however, how animals encode and transmit fear visual information is unclear. To evaluate the response characteristics of neurons in SC and LP thalamic nuclei under fear visual stimuli, extracellular action potentials (spikes) and local field potential (LFP) signals were recorded under looming and dimming visual stimuli. The results showed that both SC and LP thalamic nuclei were strongly responsive to looming visual stimuli but not sensitive to dimming visual stimuli. Under the looming visual stimulus, the theta (θ) frequency bands of both nuclei showed obvious oscillations, which markedly enhanced the synchronization between neurons. The functional network characteristics also indicated that the network connection density and information transmission efficiency were higher under fear visual stimuli. These findings suggest that both SC and LP thalamic nuclei can effectively identify threatening fear visual information and rapidly transmit it between nuclei through the θ frequency band. This discovery can provide a basis for subsequent coding and decoding studies in the subcortical visual pathways.

The effect of nursing intervention based on the staged behaviour change on recovery, quality of life, and self-efficacy of diabetic patients with scalds.

This study aimed to explore the impact of nursing intervention based on staged behaviour change (SBC) on the quality of life (QoL) and self-efficacy of diabetic patients with scalds. From January 2020 to January 2021, a total of 82 consecutive cases with diabetes and scalds were prospectively enrolled in this study. They were divided into the SBC group (41 cases were given SBC-based nursing intervention) and the control group (41 cases were given routine intervention) using the random number table method. The granulation tissue growth time and wound healing time were compared between the two groups. Pain intensity, QoL, self-efficacy, and score of wound exudation at 3, 7, and 15 days after intervention were observed. The granulation tissue growth time and wound healing time of the SBC group were lower than those of the control group with statistical difference (P < 0.05). The 3-, 5-, and 7-day pain intensity of the SBC group were all lower than those of the control group, with statistical difference (P < 0.05, respectively). Before intervention, there were no significant differences in mental health, role emotional, social function, vitality status, physical pain, role physical, physical function, and general health between the two groups (P > 0.05, respectively). After intervention, the above indicators of the SBC group were significantly higher than those of the control group (P < 0.05, respectively). Before intervention, there were no significant differences between the two groups in communication with doctors, emotional communication, role function, symptom management, medication as prescribed, and control of water and salt intake and nutrition (P > 0.05, respectively). After intervention, the above indicators in the SBC group were all significantly higher than those in the control group (P < 0.05, respectively). The score of wound exudation of the SBC group was lower than that of the control group after intervention (P < 0.05). SBC-based nursing intervention can effectively improve the QoL and self-efficacy of diabetic patients with scalds and can effectively promote wound healing, and can be recommended for clinical use.

Simplified Near-Degenerate Four-Wave-Mixing Microscopy.

Four-wave-mixing microscopy is widely researched in both biology and medicine. In this paper, we present a simplified near-degenerate four-wave-mixing microscopy (SNDFWM). An ultra-steep long-pass filter is utilized to produce an ultra-steep edge on the spectrum of a femtosecond pulse, and a super-sensitive four-wave-mixing (FWM) signal can be generated via an ultra-steep short-pass filter. Compared with the current state-of-the-art FWM microscopy, this SNDFWM microscopy has the advantages of simpler experimental apparatus, lower cost, and easier operation. We demonstrate that this SNDFWM microscopy has high sensitivity and high spatial resolution in both nanowires and biological tissues. We also show that the SNDFWM microscopy can achieve an ultra-sensitive detection based on the electron-resonance effect. This method might find an important application in tracking of nano drugs in vivo.

Effect of vacuum sealing drainage on healing time and inflammation-related indicators in patients with soft tissue wounds.

The aim of this study was to investigate the therapeutic effects of vacuum sealing drainage (VSD) on wound repair time and inflammation-related indicators in patients with soft-tissue wounds in comparison with traditional treatment. From January 2018 to January 2020, 130 enrolled patients with soft-tissue wounds were randomly divided into two groups: VSD group (65 cases) and routine dressing change (RDC) group (65 cases). The inflammation-related indicators including erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), white blood cell (WBC), and procalcitonin (PCT) of preoperative stage and postoperative day 3 (POD 3) and POD 7 were recorded. Wound healing was observed 3 and 7 days after treatment, and the clinical efficacy, changes in the wound (coverage rate and thickness of granulation tissue and bacterial clearance rate), wound-cleaning time, wound-healing time, and hospital stay time were recorded after treatment as well. No significant difference was observed in terms of the baseline between the two groups. On POD 3 and POD 7, CRP, WBC, and PCT levels in the VSD group were lower than those in the RDC group, while ESR levels were higher, with significant differences (P < .05). After treatment, the wound-cleaning time, wound-healing time, and hospital length of stay of the VSD group were all lower than those of the RDC group, with significant differences (P < .05). VSD has a significant effect on the treatment of patients with soft-tissue wounds, which can effectively shorten the time of wound healing and reduce inflammation-related indicators. Compared with traditional RDC, VSD is more worthy of clinical application.

Influence of incentive nursing intervention on recovery of burn patients after vacuum sealing drainage.

To observe the effect of application of incentive nursing intervention (INI) on recovery in burn patients undergoing vacuum sealing drainage (VSD). From January 2017 to January 2020, a total of 82 consecutive burn patients were prospectively enrolled, and divided into INI group and routine nursing intervention (RNI) group according to random number table method. The causes of inadequate drainage were collected, the incidence was calculated, and the occurrence of inadequate drainage at different locations was compared. The pain degree and comfort status before and after the intervention were observed, and the wound healing time, hospital stay, and satisfaction after the intervention were recorded. The reasons for inadequate drainage during the treatment of VSD included negative pressure insufficient, drainage tube blockage because of escharosis, replacement of negative pressure internal sac not standard, loose sealing of the semi-permeable membrane, and the negative pressure tube fell off, compressed or reflexed. The baseline characteristics between the two groups were comparable (P > .05). The incidence of each cause and total incidence of inadequate drainage in INI group were lower than those in RNI group (P < .05, respectively). The incidences of inadequate drainage of all burn sites in INI group were lower than those in RNI group, and the difference of limbs wound between the two group was statistically significant (P < .05). After intervention, the pain intensity of INI group was lower than that of RNI group (P < .05), and the holistic comfort of INI group was higher than that of RNI group (P < .05). The wound healing time and hospital stay time in INI group were lower than those in RNI group, and the total satisfaction rate in INI group was higher than that in RNI group (P < .05, respectively). Applying INI can effectively reduce the incidence of insufficient drainage, reduce pain, improve comfort, shorten wound healing time and hospital stay, and thus improve the overall satisfaction rate of patients, which is worthy of clinical promotion and application.

Cx43 promotes SHF-DPCs proliferation in the hair follicle of Albas cashmere goats from anagen to telogen.

Connexin 43 (Cx43), known to form gap junction transmembrane channels between the cytoplasm of two adjacent cells, plays a key role in physiological functions, such as regulating cell growth, differentiation, and maintaining tissue homeostasis. Cashmere goat is an important farm animal that provides cashmere, which was produced by secondary hair follicles (SHF), for human consumption; however, there is no report about the role of Cx43 on the growth and development of SHF in cashmere goat. In this study, we investigated the effect of Cx43 on proliferation secondary hair follicle dermal papilla cells (SHF-DPCs) in Albas cashmere goat. In SHF-DPCs, Cx43 overexpression promoted cell proliferation and upregulated the expression of IGF-1, whereas Cx43 knockdown was associated with the opposite effects. These results suggested that Cx43 may promote cell proliferation by inducing IGF-1. Overall, our research not only contributes to a better understanding of the mechanism of the growth and development of SHF in cashmere goat, but also shed light on cashmere quality control in the future.

Thymosin ß4 Identified by Transcriptomic Analysis from HF Anagen to Telogen Promotes Proliferation of SHF-DPCs in Albas Cashmere Goat.

Increasing cashmere yield is one of the important goals of cashmere goat breeding. To achieve this goal, we screened the key genes that can improve cashmere performance. In this study, we used the RNA raw datasets of the skin and dermal papilla cells of secondary hair follicle (SHF-DPCs) samples of hair follicle (HF) anagen and telogen of Albas cashmere goats and identified a set of significant differentially expressed genes (DEGs). To explore potential associations between gene sets and SHF growth features and to identify candidate genes, we detected functional enrichment and constructed protein-protein interaction (PPI) networks. Through comprehensive analysis, we selected Thymosin ß4 (Tß4), Rho GTPase activating protein 6 (ARHGAP6), ADAM metallopeptidase with thrombospondin type 1 motif 15, (ADAMTS15), Chordin (CHRD), and SPARC (Osteonectin), cwcv and kazal-like domains proteoglycan 1 (SPOCK1) as candidate genes. Gene set enrichment analysis (GSEA) for these genes revealed Tß4 and ARHGAP6 have a close association with the growth and development of SHF-DPCs. However, the expression of Tß4 in the anagen was higher than that in the telogen, so we finally chose Tß4 as the ultimate research object. Overexpressing Tß4 promoted and silencing Tß4 inhibited the proliferation of SHF-DPCs. These findings suggest that Tß4 can promote the growth and development of SHF-DPCs and indicate that this molecule may be a valuable target for increasing cashmere production.

Single beam low frequency 2D Raman spectroscopy.

Low frequency Raman spectroscopy resolves the slow vibrations resulting from collective motions of molecular structures. This frequency region is extremely challenging to access via other multidimensional methods such as 2D-IR. In this paper, we describe a new scheme which measures 2D Raman spectra in the low frequency regime. We separate the pulse into a spectrally shaped pump and a transform-limited probe, which can be distinguished by their polarization states. Low frequency 2D Raman spectra in liquid tetrabromoethane are presented, revealing coupling dynamics at frequencies as low as 115 cm-1. The experimental results are supported by numerical simulations which replicate the key features of the measurement. This method opens the door for the deeper exploration of vibrational energy surfaces in complex molecular structures.

Cyano-borrowing: titanium-catalyzed direct amination of cyanohydrins with amines and enantioselective examples.

The direct amination of cyanohydrins with amines via a catalytic cyano-borrowing reaction was developed. The transformation features broad substrate scope, excellent functional group compatibility, and very mild and simple operations. Moreover, a titanium catalyst supported by quinine and (S)-BINOL ligands enabled an asymmetric cyano-borrowing reaction with moderate to high enantioselectivity.

Bioinformatics analysis reveals 6 key biomarkers associated with non-small-cell lung cancer.

OBJECTIVE: Non-small-cell lung cancer (NSCLC) accounts for >85% of lung cancers, and its incidence is increasing. We explored expression differences between NSCLC and normal cells and predicted potential target sites for detection and diagnosis of NSCLC. METHODS: Three microarray datasets from the Gene Expression Omnibus database were analyzed using GEO2R. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis were conducted. Then, the String database, Cytoscape, and MCODE plug-in were used to construct a protein-protein interaction (PPI) network and screen hub genes. Overall and disease-free survival of hub genes were analyzed using Kaplan-Meier curves, and the relationship between expression patterns of target genes and tumor grades were analyzed and validated. Gene set enrichment analysis and receiver operating characteristic curves were used to verify enrichment pathways and diagnostic performance of hub genes. RESULTS: In total, 293 differentially expressed genes were identified and mainly enriched in cell cycle, ECM-receptor interaction, and malaria. In the PPI network, 36 hub genes were identified, of which 6 were found to play significant roles in carcinogenesis of NSCLC: CDC20, ECT2, KIF20A, MKI67, TPX2, and TYMS. CONCLUSION: The identified target genes can be used as biomarkers for the detection and diagnosis of NSCLC.

High-speed low-frequency chirped coherent anti-Stokes Raman scattering microscopy using an ultra-steep long-pass filter.

Coherent anti-Stokes Raman scattering (CARS) microscopy is becoming a more common tool in biomedical research. High-speed CARS microscopy has important applications in live cell imaging and in label-free pathology. However, only a few realizations exist of CARS imaging applied in the few terahertz spectral range (<300 cm-1), in which much is unknown to date. Although single-beam CARS microscopy proved to be robust in this low-frequency region, pixel-dwell time using presently available schemes is still relatively long, in the millisecond scale. Single-beam notch-shaped chirped-CARS (C-CARS) microscopy in the fingerprint region can be performed without using lock-in detection, yet it necessitates double-notch shaping, resulting in a relatively complex system. Here, we demonstrate that C-CARS in the low-frequency regime can be achieved using a sharp-edge, which is created by an ultra-steep long-pass filter (ULPF). Furthermore, we demonstrate that this variant of C-CARS spectroscopy can be performed without post-processing analyses. This is used to image collagen in a biological sample with a pixel dwell time of 200 microseconds. This sharp-edge C-CARS method may find important application in rapid low-frequency CARS imaging of live cells or for imaging of fast flowing objects such as in microfluidic channels.

Integrative Analysis of Methylation and Transcriptional Profiles to Reveal the Genetic Stability of Cashmere Traits in the Tß4 Overexpression of Cashmere Goats.

DNA methylation alteration is frequently observed in exogenous gene silencing and may play important roles in the genetic stability of traits. Cashmere is derived from the secondary hair follicles (SHFs) of cashmere goats, which are morphogenetically distinct from primary hair follicles (PHFs). Here, in light of having initially produced 15 Tß4 overexpression (Tß4-OE) cashmere goats which had more SHFs than the wild type (WT) goats, and produced more cashmere, we produced Tß4-OE offsprings both via somatic cell nuclear transfer (SCNT) and via natural mating (NM). However, the desired trait exhibited lower fixation in the line-bred offspring compared to the SCNT offspring. Integrative analysis of methylation and transcriptional profiles showed that this might be due to the influence of methylation on the expression of differentially expressed genes (DEGs) between generations, which was mutually consistent with the results of the functional and pathway enrichment analysis of differentially methylated regions (DMRs) and DEGs. Overall, our study systematically describes the DNA methylation characteristics between generations of cashmere goats and provides a basis for improving genetic stability.

Titanium-Catalyzed Cyano-Borrowing Reaction for the Direct Amination of Cyanohydrins with Ammonia.

α-Aminonitrile was an important building block in natural products and key intermedia in organic chemistry. Herein, the direct amination of cyanohydrins with the partner of ammonia to synthesis N-unprotected α-aminonitriles is developed. The reaction proceeds via titanium-catalyzed cyano-borrowing reaction, which features high atom economy and simple operation. A broad range of ketone or aldehyde cyanohydrins was tolerated with ammonia, and the N-unprotected α-aminonitriles were synthesis with moderate to high yields under mild reaction conditions.

Simplified approach to low-frequency coherent anti-Stokes Raman spectroscopy using a sharp spectral edge filter.

Coherent anti-Stokes Raman scattering (CARS) has found wide applications in biomedical research. Compared with alternatives, single-beam CARS is especially attractive at low frequencies. Yet, currently existing schemes necessitate a relatively complicated setup to perform high-resolution spectroscopy. Here we show that the spectral sharp edge formed by an ultra-steep long-pass filter is sufficient for performing CARS spectroscopy, simplifying the system significantly. We compare the sensitivity of the presented methodology with available counterparts both theoretically and experimentally. Importantly, we show that this method, to the best of our knowledge, is the simplest and most suitable for vibrational imaging and spectroscopy in the very low-frequency regime (<200 cm-1).

Cyano-borrowing reaction: nickel-catalyzed direct conversion of cyanohydrins and aldehydes/ketones to ß-cyano ketone.

A direct nickel-catalyzed, high atom- and step-economical reaction of cyanohydrins with aldehydes or ketones via an unprecedented "cyano-borrowing reaction" has been developed. Cleavage of the C-CN bond of cyanohydrins followed by aldol condensation and conjugate addition of cyanide to α,ß-unsaturated ketones proceeded to deliver a range of racemic ß-cyano ketones with good to high yields. The practical procedure with the use of a commercial and less-toxic CN source bodes well for wide application of this protocol.

Impulsive Raman spectroscopy via precision measurement of frequency shift with low energy excitation.

Stimulated Raman scattering (SRS) has recently become useful for chemically selective bioimaging. It is usually measured via modulation transfer from the pump beam to the Stokes beam. Impulsive stimulated Raman spectroscopy, on the other hand, relies on the spectral shift of ultrashort pulses as they propagate in a Raman active sample. This method was considered impractical with low energy pulses since the observed shifts are very small compared to the excitation pulse bandwidth, spanning many terahertz. Here we present a new apparatus, using tools borrowed from the field of precision measurement, for the detection of low-frequency Raman lines via stimulated-Raman-scattering-induced spectral shifts. This method does not require any spectral filtration and is therefore an excellent candidate to resolve low-lying Raman lines (<200 cm-1), which are commonly masked by the strong Rayleigh scattering peak. Having the advantage of the high repetition rate of the ultrafast oscillator, we reduce the noise level by implementing a lock-in detection scheme with a wavelength shift sensitivity well below 100 fm. This is demonstrated by the measurement of low-frequency Raman lines of various liquid samples.

A dynamic loading method for controlling on-chip microfluidic sample injection.

A new technique for controlling discrete sample injection in straight-cross microfluidic chips is presented here. This technique involves a three-part process with a dynamic loading step in between the steady-state loading step and the dispensing step. During the intermediate step, sample is pumped into the intersection and into the three connecting channels. The key features of this technique are the ability to dynamically control the sample size and the ability to inject well-defined samples at the original sample concentration. Injections of these samples with lengths varying from 2 channel widths (100 microm) to 20 channel widths (millimeter-sized) are demonstrated. The sample concentration profiles obtained are compared with those of focused and less-focused pinched-valve injections. In applications such as high-speed capillary zone electrophoresis, this technique can provide an increase in signal with a small increase in sample length. This technique is especially applicable to many large-sample applications in which the offset twin-T microchip has been previously employed.