Baicalin promotes random-pattern skin flap survival by inducing autophagy via AMPK-regulated TFEB nuclear transcription.

The random-pattern skin flap is a generally used technique to cover the soft tissue defect, while its application is often constrained by complications after the flap transplant. Necrosis of the flap remains a principal obstacle. The purpose of this study was to investigate the effect of Baicalin on skin flap survival and its mechanism. First of all, we discovered that administering Baicalin stimulated cell migration and boosted the formation of capillary tubes in human umbilical vein endothelial cells. Then, we detected that Baicalin reduced apoptosis-induced oxidative stress by using western blot and oxidative stress test kit. After that, we observed that Baicalin increased autophagy and utilized 3MA to block autophagy augmentation substantially reversing the effects of Baicalin therapy. Furthermore, we uncovered the underlying mechanisms of Baicalin-induced autophagy via AMPK-regulated TFEB nuclear transcription. Finally, our in vivo experiment findings showed that Baicalin reduces oxidative stress, inhibits apoptosis, promotes angiogenesis, and boosts the levels of autophagy. After autophagy was blocked, substantially reversing the effects of Baicalin therapy. Our study indicated that Baicalin-induced autophagy via AMPK regulated TFEB nuclear transcription and then promotes angiogenesis and against oxidative stress and apoptotic promotes skin flap survival. These findings highlight the therapeutic potential for the clinical application of Baicalin in the future.

Bionic orientation method based on polarization imaging in HDR scenes.

An increasing number of bio-inspired navigation approaches have been designed based on polarization cameras. However, digital cameras can sense a much narrower field of vision than the vision of insects or human beings. In this study, we propose an adaptive skylight polarized orientation method for high dynamic range (HDR) scenes. Initially, we built a model of the image acquisition pipeline that can recover HDR irradiance maps from polarization images. Subsequently, the orientation method was designed based on a combination of the irradiance maps and the least squares methods. Some preprocessing steps were utilized to eliminate occlusion interference. In addition, an autoexposure adjustment method was proposed using information entropy and heuristic segmentation. Finally, the experimental results show that the proposed method can improve the accuracy of bionic orientation and adaption to skylight with occlusions and interference in natural conditions.

Risk of pedicle and spinous process violation during cortical bone trajectory screw placement in the lumbar spine.

BACKGROUND: Previous studies have confirmed the feasibility of the cortical bone trajectory (CBT) technique. However, there are few reports on spinous process violation and screw penetration during the screw insertion. The purpose of this study was to evaluate the incidence of spinous process violation and screw penetration through the pedicle during CBT screw insertion. METHODS: Computed tomography (CT) scans with normal lumbar structures were consecutively obtained and three-dimensional (3D) reconstructions of the lumbar spine were created. Bilateral CBT screw placement was simulated on each segment using a screw diameter of 4.5 mm, 5.0 mm, or 5.5 mm. Incidences of these complications were recorded and analyzed. RESULTS: A total of 90 patients were enrolled. Spinous process violation was observed in 68.3, 53.3, 25.5, 1.7, and 0% from L1 to L5, respectively, using 4.5 mm screws. A significant difference was found among the five segments but this was unconnected to gender or screw diameter. The incidence of screw penetration through the inner wall decreased from L1 to L4; in turn, L1 (16.7-35.5%), L2 (12.7-34.4%), L3 (2.8-23.8%) and L4 (1.1-6.7%). This trend was reversed in L5 (6.7-16.7%). Moreover, screw penetration through the outer wall was rare. The incidence of screw penetration varied with screw size as well as lumbar level, but not with gender. CONCLUSIONS: There are more difficulties of CBT screw fixation in upper lumbar spine. The low rate of screw penetration, using 4.5 mm screws, suggests the safety for CBT fixation in the lumbar spine. Larger screws (5.0 mm or 5.5 mm) are more recommended for use in the lower lumbar spine. Moreover, CBT fixation in L5 deserves greater attention because of the unique morphology of the pedicle.

Sinomenine Attenuates Traumatic Spinal Cord Injury by Suppressing Oxidative Stress and Inflammation via Nrf2 Pathway.

Traumatic spinal cord injury (SCI) is a devastating condition with few efficacious drugs. Sinomenine, a bioactive alkaloid extracted from medicinal herb, has been used as a treatment of rheumatoid diseases. This present study explored the therapeutic effects of sinomenine on locomotor dysfunction and neuropathology in SCI. Our findings revealed that sinomenine mitigated neurological deficits and enhanced neuronal preservation, paralleled with a reduction of apoptosis. Also, sinomenine significantly reduced inflammatory cytokines and oxidative stress factors. We further examined erythroid-2-related factor 2 (Nrf2) nuclear translocation, which mainly controls the coordinated expression of important antioxidant and detoxification genes. An increase in Nrf2 translocation from cytoplasm to nucleus and Nrf2-mediated transactivation was observed after sinomenine administration. Knocking down Nrf2 by siRNA could counteract sinomenine-mediated anti-oxidant stress and anti-inflammation following H2O2-stimulated and LPS-stimulated PC12 cells. Together, our findings indicated that sinomenine has the potential to be an effective therapeutic agent for SCI by inhibiting inflammation and oxidative stress via Nrf2 activation.

Asperosaponin VI promotes angiogenesis and accelerates wound healing in rats via up-regulating HIF-1α/VEGF signaling.

Wound therapy remains a clinical challenge due to the complexity of healing pathology and high demand of achieving functional and aesthetically satisfactory scars. Newly formed blood vessels are essential for tissue repair since they can support cells at the wound site with nutrition and oxygen. In this study, we investigated the effects of Asperosaponin VI (ASA VI) isolated from a traditional Chinese medicine, the root of Dipsacus asper Wall, in promoting angiogenesis, as well as its function in wound therapeutics. Treatment of human umbilical vein endothelial cells (HUVECs) with ASA VI (20-80 µg/mL) dose-dependently promoted the proliferation, migration and enhanced their angiogenic ability in vitro, which were associated with the up-regulated HIF-1α/VEGF signaling. Full-thickness cutaneous wound model rats were injected with ASA VI (20 mg·kg-1·d-1, iv) for 21 d. Administration of ASA VI significantly promoted the cutaneous wound healing, and more blood vessels were observed in the regenerated tissue. Due to rapid vascularization, the cellular proliferation status, granulation tissue formation, collagen matrix deposition and remodeling processes were all accelerated, resulting in efficient wound healing. In summary, ASA VI promotes angiogenesis of HUVECs in vitro via up-regulating the HIF-1α/VEGF pathway, and efficiently enhances the vascularization in regenerated tissue and facilitates wound healing in vivo. The results reveal that ASA VI is a potential therapeutic for vessel injury-related wounds.

Design and Calibration of a Novel Bio-Inspired Pixelated Polarized Light Compass.

Animals, such as Savannah sparrows and North American monarch butterflies, are able to obtain compass information from skylight polarization patterns to help them navigate effectively and robustly. Inspired by excellent navigation ability of animals, this paper proposes a novel image-based polarized light compass, which has the advantages of having a small size and being light weight. Firstly, the polarized light compass, which is composed of a Charge Coupled Device (CCD) camera, a pixelated polarizer array and a wide-angle lens, is introduced. Secondly, the measurement method of a skylight polarization pattern and the orientation method based on a single scattering Rayleigh model are presented. Thirdly, the error model of the sensor, mainly including the response error of CCD pixels and the installation error of the pixelated polarizer, is established. A calibration method based on iterative least squares estimation is proposed. In the outdoor environment, the skylight polarization pattern can be measured in real time by our sensor. The orientation accuracy of the sensor increases with the decrease of the solar elevation angle, and the standard deviation of orientation error is 0 . 15 ∘ at sunset. Results of outdoor experiments show that the proposed polarization navigation sensor can be used for outdoor autonomous navigation.

Tightly-coupled stereo visual-inertial navigation using point and line features.

This paper presents a novel approach for estimating the ego-motion of a vehicle in dynamic and unknown environments using tightly-coupled inertial and visual sensors. To improve the accuracy and robustness, we exploit the combination of point and line features to aid navigation. The mathematical framework is based on trifocal geometry among image triplets, which is simple and unified for point and line features. For the fusion algorithm design, we employ the Extended Kalman Filter (EKF) for error state prediction and covariance propagation, and the Sigma Point Kalman Filter (SPKF) for robust measurement updating in the presence of high nonlinearities. The outdoor and indoor experiments show that the combination of point and line features improves the estimation accuracy and robustness compared to the algorithm using point features alone.

An evaluation of skylight polarization patterns for navigation.

Skylight polarization provides a significant navigation cue for certain polarization-sensitive animals. However, the precision of the angle of polarization (AOP) of skylight for vehicle orientation is not clear. An evaluation of AOP must be performed before it is utilized. This paper reports an evaluation of AOP of skylight by measuring the skylight polarization patterns of clear and cloudy skies using a full-sky imaging polarimetry system. AOP measurements of skylight are compared with the pattern calculated by the single-scattering Rayleigh model and these differences are quantified. The relationship between the degree of polarization (DOP) and the deviation of AOP of skylight is thoroughly studied. Based on these, a solar meridian extracted method is presented. The results of experiments reveal that the DOP is a key parameter to indicate the accuracy of AOP measurements, and all the output solar meridian orientations extracted by our method in both clear and cloudy skies can achieve a high accuracy for vehicle orientation.

Compass information extracted from a polarization sensor using a least-squares algorithm.

Skylight polarization provides a significant navigation cue for certain polarization-sensitive animals. We designed a polarization navigation sensor based on the polarization sensitivity mechanism of insects. In this paper, the principle of our polarization navigation sensor is introduced. The relationship between the degree of polarization (DOP) and the error of the angle of polarization (AOP) is examined. A new DOP and AOP calculation algorithm using a linear least-squares algorithm is presented. The results of simulation and experiments reveal the essentiality of DOP calculation and demonstrate the efficiency and accuracy of the proposed algorithm.

Design of a device for sky light polarization measurements.

Sky polarization patterns can be used both as indicators of atmospheric turbidity and as a sun compass for navigation. The objective of this study is to improve the precision of sky light polarization measurements by optimal design of the device used. The central part of the system is composed of a Charge Coupled Device (CCD) camera; a fish-eye lens and a linear polarizer. Algorithms for estimating parameters of the polarized light based on three images are derived and the optimal alignments of the polarizer are analyzed. The least-squares estimation is introduced for sky light polarization pattern measurement. The polarization patterns of sky light are obtained using the designed system and they follow almost the same patterns of the single-scattering Rayleigh model. Deviations of polarization angles between observation and the theory are analyzed. The largest deviations occur near the sun and anti-sun directions. Ninety percent of the deviations are less than 5° and 40% percent of them are less than 1°. The deviations decrease evidently as the degree of polarization increases. It also shows that the polarization pattern of the cloudy sky is almost identical as in the blue sky.

A novel angle computation and calibration algorithm of bio-inspired sky-light polarization navigation sensor.

Navigation plays a vital role in our daily life. As traditional and commonly used navigation technologies, Inertial Navigation System (INS) and Global Navigation Satellite System (GNSS) can provide accurate location information, but suffer from the accumulative error of inertial sensors and cannot be used in a satellite denied environment. The remarkable navigation ability of animals shows that the pattern of the polarization sky can be used for navigation. A bio-inspired POLarization Navigation Sensor (POLNS) is constructed to detect the polarization of skylight. Contrary to the previous approach, we utilize all the outputs of POLNS to compute input polarization angle, based on Least Squares, which provides optimal angle estimation. In addition, a new sensor calibration algorithm is presented, in which the installation angle errors and sensor biases are taken into consideration. Derivation and implementation of our calibration algorithm are discussed in detail. To evaluate the performance of our algorithms, simulation and real data test are done to compare our algorithms with several exiting algorithms. Comparison results indicate that our algorithms are superior to the others and are more feasible and effective in practice.

Analysis of genomic copy number variations through whole-genome scan in Yunling cattle.

Yunling cattle is a new breed of beef cattle bred in Yunnan Province, China, which has the advantages of fast growth, excellent meat quality, improved tolerance ability, and important landscape value. Copy number variation (CNV) is a significant source of gene structural variation and plays a crucial role in evolution and phenotypic diversity. Based on the latest reference genome ARS-UCD2.0, this study analyzed the genome-wide distribution of CNVs in Yunling cattle using short-read whole-genome sequencing data (n = 129) and single-molecule long-read sequencing data (n = 1), and a total of 16,507 CNVs were detected. After merging CNVs with overlapping genomic positions, 3,728 CNV regions (CNVRs) were obtained, accounting for 0.61% of the reference genome. The functional analysis indicated significant enrichment of CNVRs in 96 GO terms and 57 KEGG pathways, primarily related to cell adhesion, signal transduction, neuromodulation, and nutritional metabolism. Additionally, 111 CNVRs overlapped with 76 quantitative trait loci (QTLs), including Subcutaneous fat thickness QTL, Longissimus muscle area QTL, and Marbling score QTL. Several CNVR-overlapping genes, including BZW1, AOX1, and LOC100138449, overlap with regions associated with meat color and quality QTLs. Furthermore, Vst analysis showed that PSMB4, ERICH1, SMC2, and PPP4R3A were highly divergent between Yunling and Brahman cattle. In summary, we have constructed the genomic CNV map of Yunling cattle for the first time using whole-genome resequencing. This provides valuable genetic variation resources for the study of the Yunling cattle genome and contributes to the study of economic traits in Yunling cattle.

Chromosome-level genome assembly and annotation of the Yunling cattle with PacBio and Hi-C sequencing data.

Yunling cattle is a new breed of beef cattle bred in Yunnan Province, China. It is bred by crossing the Brahman, the Murray Grey and the Yunnan Yellow cattle. Yunling cattle can adapt to the tropical and subtropical climate environment, and has good reproductive ability and growth speed under high temperature and high humidity conditions, it also has strong resistance to internal and external parasites and with good beef performance. In this study, we generated a high-quality chromosome-level genome assembly of a male Yunling cattle using a combination of short reads sequencing, PacBio HiFi sequencing and Hi-C scaffolding technologies. The genome assembly(3.09 Gb) is anchored to 31 chromosomes(29 autosomes plus one X and Y), with a contig N50 of 35.97 Mb and a scaffold N50 of 112.01 Mb. It contains 1.62 Gb of repetitive sequences and 20,660 protein-coding genes. This first construction of the Yunling cattle genome provides a valuable genetic resource that will facilitate further study of the genetic diversity of bovine species and accelerate Yunling cattle breeding efforts.

Measurement and observation of the first web space based on morphology and clinical applications.

PURPOSE: To describe and evaluate the anatomical skin shape of the first web space in cadavers and to guide flap design for this area. METHODS: Twelve cadavers (24 hands on both sides) were selected. Marker points were chosen based on the characteristics of the first web for morphological measurement and observation. The morphological characteristics of the first web under the radial or palmar abduction position of the thumb were measured and compared. The best morphologic features and parameters of the first web repairing flap were obtained. RESULTS: When the thumb was in the palmar abduction position, the maximum distance a(p) was 6.78 ± 0.72 cm and the skin area s(p) was 20.09 ± 2.63 cm2, both of which were significantly greater than the distance a(r) of 5.86 ± 0.74 cm and the skin area s(r) of 17.39 ± 2.15 cm2 when the thumb was in the radial abduction position (P < 0.05). There was no significant difference in the length b(r) and b(p) of the long axis of the flap between two different abduction positions (P > 0.05). It is found that the shape of the first web area was not a symmetrical spindle but an irregular quadrilateral inclined to the index finger side. CONCLUSION: The flap design and measurement for the first web space covering should take the maximum palmar abduction position of the thumb as a reference. The asymmetric quadrilateral flap design is more in line with the anatomical and morphological characteristics of the region.

A Pose-Only Solution to Visual Reconstruction and Navigation.

Visual navigation and three-dimensional (3D) scene reconstruction are essential for robotics to interact with the surrounding environment. Large-scale scenarios and computational robustness are great challenges facing the research community to achieve this goal. This paper raises a pose-only imaging geometry representation and algorithms that might help solve these challenges. The pose-only representation, equivalent to the classical multiple-view geometry, is discovered to be linearly related to camera global translations, which allows for efficient and robust camera motion estimation. As a result, the spatial feature coordinates can be analytically reconstructed and do not require nonlinear optimization. Comprehensive experiments demonstrate that the computational efficiency of recovering the scene and associated camera poses is significantly improved by 2-4 orders of magnitude.

Population Structure and Genetic Diversity of Yunling Cattle Determined by Whole-Genome Resequencing.

The Yunling cattle breed, a three-breed crossbreed, which comprises 50% Brahman cattle, 25% Murray Grey cattle and 25% Yunnan Yellow cattle, has several advantageous traits, including rapid growth, superior meat quality, ability to improve tolerance in hot and humid climates, tick resistance and rough feed. It can be rightfully stated that Yunling cattle serve as vital genetic repositories of the local Yunnan cattle. Gaining insights into the genetic information of Yunling cattle plays a significant role in the formulation of sound breeding strategies for this breed, safeguarding genetic resources and mitigating the risks associated with inbreeding depression. In this study, we constructed the Yunling cattle standard reference genome and aligned the whole genomes of 129 Yunling cattle individuals to the constructed reference genome to estimate the current genetic status of Yunling cattle in Yunnan Province, China. The average alignment rate and the average percentage of properly paired are both 99.72%. The average nucleotide diversity in Yunling cattle is 0.000166, which indicates a lower level of diversity. Population structure analysis classified Yunling cattle into two subgroups. Inbreeding analysis revealed that inbreeding events did occur in the Yunling cattle, which may have contributed to the low genetic diversity observed. This study presents a comprehensive assessment of the genetic structure and diversity among the Yunling cattle and provides a theoretical foundation for the preservation and exploitation of these precious germplasm resources.

Andrographolide mitigates IL­1ß­induced human nucleus pulposus cells degeneration through the TLR4/MyD88/NF­κB signaling pathway.

Intervertebral disc degeneration (IDD) is a multifactorial disease with few efficacious clinical drugs, which has been demonstrated to be associated with nucleus pulposus (NP) cells apoptosis and degeneration of the extracellular matrix (ECM). Interleukin (IL)­1ß, a common proinflammatory cytokine, is considered to be one of key regulators in IDD development. Andrographolide (AG), extracted from Andrographis paniculata, has been suggested to possess marked anti­inflammatory properties. However, the effects of AG on IDD has not been well explored. The present study aimed to investigate the effects and the mechanisms of AG on IDD in human NP cells. NP cells were treated with IL­1ß in the absence or presence of AG to investigate the effects on cell viability, cellular apoptosis, production of ECM and matrix metalloproteinase (MMP)­3, MMP­9 and MMP­13, and a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS)­4 and ADAMTS­5. It was identified that IL­1ß­induced NP cellular apoptosis was significantly inhibited by AG treatment. Furthermore, AG mitigated the IL­1ß­induced degeneration of the ECM, which was paralleled by a decrease in MMPs and ADAMTS levels. In addition, AG exhibited marked inhibitory properties against the activation of Toll­like receptors (TLRs), Myeloid differentiation factor 88 (MyD88) and the nuclear translocation of Nuclear factor kappa­light­chain­enhancer of activated B cells (NF­κB). Taken together, these results demonstrated that AG treatment mitigated IL­1ß­induced NP cells degeneration through the TLR4/MyD88/NF­κB signaling pathway, and suggested that AG may be a potential agent for IDD prevention and therapy.

Feasibility of Modified Anterior Odontoid Screw Fixation: Analysis of a New Trajectory Using 3-Dimensional Simulation Software.

BACKGROUND: Anterior odontoid screw fixation (AOSF) has been suggested as the optimal treatment for type II and some shallow type III odontoid fractures. However, only the classical surgical trajectory is available; no newer entry points or trajectories have been reported. METHODS: We evaluated the anatomic feasibility of a new trajectory for AOSF using 3-dimensional (3D) screw insertion simulation software (Mimics). Computed tomography (CT) scans of patients (65 males and 59 females) with normal cervical structures were obtained consecutively, and the axes were reconstructed in 3 dimensions by Mimics software. Then simulated operations were performed using 2 new entry points below the superior articular process using bilateral screws of different diameters (group 1: 4 mm and 4 mm; group 2: 4 mm and 3.5 mm; group 3: 3.5 mm and 3.5 mm). The success rates and the required screw lengths were recorded and analyzed. RESULTS: The success rates were 79.03% for group 1, 95.16% for group 2, and 98.39% for group 3. The success rates for groups 2 and 3 did not differ significantly, and both were significantly better than the rate for group 1. The success rate was much higher in males than in females in group 1, but the success rate was similar in males and females in the other 2 groups. Screw lengths did not differ significantly among the 3 groups, but an effect of sex was apparent. CONCLUSIONS: Our modified trajectory is anatomically feasible for fixation of anterior odontoid fractures, but further anatomic experiments and clinical research are needed.

Risk Factors for Dural Tears in Thoracic and Lumbar Burst Fractures Associated With Vertical Laminar Fractures.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To reveal the risk factors for dural tears in thoracic and lumbar (TL) burst fractures associated with vertical laminar fractures through multivariate analysis. SUMMARY OF BACKGROUND DATA: Dural tears associated with laminar fractures in patients with TL burst fractures represents a special group requires distinct treatment with different surgical prognosis. It is still very difficult to predict dural tears in patients with vertical laminar fractures. The risk factors for dural tears have seldom been evaluated. METHODS: Medical records of 113 patients of TL burst fractures with vertical laminar fractures were reviewed. The data were subdivided into two groups consisting of patients with and without dural tears. Demographic information, preoperative clinical, and radiological characteristics were compared between the groups. Multivariate logistic regression models were employed to determine the independent risk factors for dural tears. RESULTS: The incidence of dural tear was 27.4% in this retrospective cohort. When compared with the dural intact group, the dural tear group had significantly worse preoperative neurological status, wider interpedicular distance, greater separation of laminar fractures, and larger encroachment of retropulsed fragment in the bony spinal canal. Multivariate stepwise logistic regression analysis showed that the ratio of interpedicular distance greater than 125% (odds ratio = 9.5; P < 0.001) and the ratio of encroachment of retropulsed fragment in the bony spinal canal of more than 50% (odds ratio = 61.2; P < 0.001) were independent risk factors for dural tears. CONCLUSION: Patients with wider interpedicular distance and larger encroachment of retropulsed fragment in the bony spinal canal were more likely to have dural tears in TL burst fractures with vertical laminar fractures. LEVEL OF EVIDENCE: 3.