Allelopathic effects of Eucalyptus extract and wood vinegar on germination and sprouting of rapeseed (Brassica rapa L.).

Eucalyptus plantations are usually characterized by low biodiversity due to allelopathy effects. Wood vinegar is considered a complex growth regulator that can promote plant growth at low concentrations. However, there is information scarcity about the co-application of eucalypt leaf water extract and wood vinegar on plants. This study aimed at clarifying whether wood vinegar can protect seed germination against suppression by eucalypt-induced allelopathy. We examined germination behavior and seedling elongation characteristics in rapeseed (Brassica rapa L.) treated with different solutions of wood vinegar and eucalypt leaf water extract. The results showed that eucalypt leaf water extracts, wood vinegar solutions, and their mixture allelopathically suppressed seed germination rate. After rapeseed sprouting, eucalypt leaf water extracts promoted root elongation, stem elongation, and fresh weight elongation. Malondialdehyde content was also lower under the influence of eucalypt leaf water extract. Mixture of high concentration of eucalypt leaf water extract and lower concentration of wood vinegar significantly promoted root elongation. Therefore, both eucalypt leaf water extract and wood vinegar are complex plant growth regulators, which can be used to inhibit or stimulate plants at different ontogenic stages. During the seed germination period, both eucalypt leaf extracts and wood vinegar could be used as weed inhibitors. Conversely, during the period of sprouting (seedling establishment), low concentrations of eucalypt leaf extracts and wood vinegar can promote growth.

Pan-cancer analysis of the prognostic significance and oncogenic role of GXYLT2.

Growing evidence supports an oncogenic role for glucoside xylosyltransferase 2 (GXYLT2) in a number of malignancies. To evaluate the prognostic value and oncogenic function of GXYLT2 in diverse cancer types, we analyzed sequencing data from public databases on 33 tumor tissues and their corresponding normal tissues. We found that GXYLT2 was overexpressed in a number of tumors, and that its expression was positively correlated with disease progression and mortality in several major cancer types including stomach adenocarcinoma (STAD). GXYLT2 was also linked to tumor size, grade, and the immune and molecular subtypes of STAD. GO and KEGG pathway analyses of GXYLT2 co-expressed genes in STAD suggested that GXYLT2 possibly plays a role in epithelial-mesenchymal transition, extracellular matrix production and degradation, angiogenesis, apoptosis, as well as in tumor inflammation, such as cytokine production and T cell activation. Finally, prognostic nomograms were created and validated for predicting 1, 3, and 5-year survival of patients with STAD. Our findings indicate that GXYLT2 may play a role in tumorigenesis and tumor immunity, and it may serve as a prognostic marker and potential immunotherapeutic target for STAD and some other types of cancer.

Significance of platelet adhesion-related genes in colon cancer based on non-negative matrix factorization-based clustering algorithm.

Background: Although surgical methods are the most effective treatments for colon adenocarcinoma (COAD), the cure rates remain low, and recurrence rates remain high. Furthermore, platelet adhesion-related genes are gaining attention as potential regulators of tumorigenesis. Therefore, identifying the mechanisms responsible for the regulation of these genes in patients with COAD has become important. The present study aims to investigate the underlying mechanisms of platelet adhesion-related genes in COAD patients. Methods: The present study was an experimental study. Initially, the effects of platelet number and related genomic alteration on survival were explored using real-world data and the cBioPortal database, respectively. Then, the differentially expressed platelet adhesion-related genes of COAD were analyzed using the TCGA database, and patients were further classified by employing the non-negative matrix factorization (NMF) analysis method. Afterward, some of the clinical and expression characteristics were analyzed between clusters. Finally, least absolute shrinkage and selection operator regression analysis was used to establish the prognostic nomogram. All data analyses were performed using the R package. Results: High platelet counts are associated with worse survival in real-world patients, and alternations to platelet adhesion-related genes have resulted in poorer prognoses, based on online data. Based on platelet adhesion-related genes, patients with COAD were classified into two clusters by NMF-based clustering analysis. Cluster2 had a better overall survival, when compared to Cluster1. The gene copy number and enrichment analysis results revealed that two pathways were differentially enriched. In addition, the differentially expressed genes between these two clusters were enriched for POU6F1 in the transcription factor signaling pathway, and for MATN3 in the ceRNA network. Finally, a prognostic nomogram, which included the ALOX12 and ACTG1 genes, was established based on the platelet adhesion-related genes, with a concordance (C) index of 0.879 (0.848-0.910). Conclusion: The mRNA expression-based NMF was used to reveal the potential role of platelet adhesion-related genes in COAD. The series of experiments revealed the feasibility of targeting platelet adhesion-associated gene therapy.

TRIM69: a marker of metastasis and potential sensitizer to 5-Fluorouracil and PD-1 blockers in colon adenocarcinoma.

BACKGROUND: Several proteins in the tripartite-motif (TRIM) family are associated with the development of colorectal cancer (CRC), but research on the role of TRIM69 was lacking. The present study examined the correlation between TRIM69 expression and colon adenocarcinoma (COAD). METHODS: mRNA sequencing data for COAD patients was extracted from The Cancer Genome Atlas to analyze correlations between TRIM69 expression and patients' clinical features as well as survival. Potential associations with immune cells and chemosensitivity also were predicted using various algorithms in the TIMER, Limma, clusterProfiler, GeneMANIA, and Gene Set Cancer Analysis platforms. Subsequently, polymerase chain reaction analysis and immunohistochemical staining were used to detect TRIM69 expression in COAD tissue samples from real-world patients. RESULTS: TRIM69 expression was lower in COAD tissues than in normal tissues and correlated with the pathologic stage and metastasis (M category). Additionally, TRIM69 was found to be involved in several immune-related pathways, notably the NOD-like signaling pathway. These results suggest that high TRIM69 expression has the potential to enhance tumor sensitivity to 5-fluorouracil and programmed cell death protein 1 (PD-1) blockers. CONCLUSIONS: From our findings that TRIM69 expression was significantly reduced in COAD compared with non-cancer tissues and associated with pathologic stage and metastasis, we conclude that increasing TRIM69 expression and/or activity may help to improve therapeutic outcomes. Accordingly, TRIM69 represents a potentially valuable marker of metastasis and target for adjuvant therapy in COAD.

Application of Tranexamic Acid in Shoulder Arthroscopic Surgery: A Randomised Controlled Trial.

Objective To explore the optimal administration route of tranexamic acid (TXA) in shoulder arthroscopic surgery. Methods Patients undergoing arthroscopic rotator cuff repair were randomly divided into four groups: control group (without TXA treatment), intravenous group (TXA was intravenously administered 10 minutes before surgery), irrigation group (TXA was added to the irrigation fluid during subacromial decompression and acromioplasty), and intravenous plus irrigation group (TXA was applied both intravenously and via intra-articular irrigation). The primary outcome was visual clarity assessed with visual analog scale (VAS) score, and the secondary outcomes included irrigation fluid consumption and time to subacromial decompression and acromioplasty procedure. Results There were 134 patients enrolled in the study, including 33 in the control group, 35 in the intravenous group, 32 in the irrigation group, and 34 in the intravenous plus irrigation group. The median and interquartile range of VAS scores for the intravenous, irrigation, and intravenous plus irrigation groups were 2.70 (2.50, 2.86) (Z = -3.677, P = 0.002), 2.67 (2.50, 2.77) (Z = -3.058, P < 0.001), and 2.91 (2.75, 3.00) (Z = -6.634, P < 0.001), respectively, significantly higher than that of the control group [2.44 (2.37, 2.53)]. Moreover, the control group consumed more irrigation fluid than the intravenous group, irrigation group, and intravenous plus irrigation group (all P < 0.05). The intravenous plus irrigation group consumed less irrigation fluid than either the intravenous group or the irrigation group (both P < 0.001). There was no difference in subacromial decompression and acromioplasty operative time among the four groups. Conclusion TXA applied both topically and systematically can improve intraoperative visual clarity, and the combined application is more effective.

Automatic segmentation of ovarian follicles using deep neural network combined with edge information.

Medical ultrasound imaging plays an important role in computer-aided diagnosis systems. In many cases, it is the preferred method of doctors for diagnosing diseases. Combined with computer vision technology, segmentation of ovarian ultrasound images can help doctors accurately judge diseases, reduce doctors' workload, and improve doctors' work efficiency. However, accurate segmentation of an ovarian ultrasound image is a challenging task. On the one hand, there is a lot of speckle noise in ultrasound images; on the other hand, the edges of objects are blurred in ultrasound images. In order to segment the target accurately, we propose an ovarian follicles segmentation network combined with edge information. By adding an edge detection branch at the end of the network and taking the edge detection results as one of the losses of the network, we can accurately segment the ovarian follicles in an ultrasound image, making the segmentation results finer on the edge. Experiments show that the proposed network improves the segmentation accuracy of ovarian follicles, and that it has advantages over current algorithms.

Comparison of comfort and complications of Implantable Venous Access Port (IVAP) with ultrasound guided Internal Jugular Vein (IJV) and Axillary Vein/Subclavian Vein (AxV/SCV) puncture in breast cancer patients: a randomized controlled study.

BACKGROUND: Axillary vein/subclavian vein (AxV/SCV) and Internal jugular vein (IJV) are commonly used for implantable venous access port (IVAP) implantation in breast cancer patients for chemotherapy. Previous research focused on comparison of complications while patient comfort was ignored. This study aims to compare patient comfort, surgery duration and complications of IVAP implantation between IJV and AxV/SCV approaches. METHODS: Two hundred forty-eight breast cancer patients were enrolled in this randomized controlled study from August 2020 to June 2021. Patients scheduled to undergo IVAP implantation were randomly and equally assigned to receive central venous catheters with either AxV /SCV or IJV approaches. All patients received comfort assessment using a comfort scale table at day 1, day 2 and day 7 after implantation. Patient comfort, procedure time of operation as well as early complications were compared. RESULTS: Patient comfort was significantly better in the AxV/SCV group than that of IJV group in day 1 (P < 0.001), day 2 (P < 0.001) and day 7(P = 0.023). Procedure duration in AxV/SCV group was slightly but significantly shorter than IJV group (27.14 ± 3.29 mins vs 28.92 ± 2.54 mins, P < 0.001). More early complications occurred in AxV/SCV group than IJV group (11/124 vs 2/124, P = 0.019). No difference of complications of artery puncture, pneumothorax or subcutaneous hematoma between these two groups but significantly more catheter misplacement in AxV/SCV group than IJV group (6/124 vs 0/124, P = 0.029). Absolutely total risk of complications was rather low in both groups (8.87% in AxV/SCV group and 1.61% in IJV group). CONCLUSIONS: Our study indicates that patients with AxV/SCV puncture have higher comfort levels than IJV puncture. AxV/SCV puncture has shorter procedure duration but higher risk of early complications, especially catheter misplacement. Both these two approaches have rather low risk of complications. Consequently, our study provides an alternative choice for breast cancer patients to reach better comfort.

Accelerate gas diffusion-weighted MRI for lung morphometry with deep learning.

OBJECTIVES: Multiple b-value gas diffusion-weighted MRI (DW-MRI) enables non-invasive and quantitative assessment of lung morphometry, but its long acquisition time is not well-tolerated by patients. We aimed to accelerate multiple b-value gas DW-MRI for lung morphometry using deep learning. METHODS: A deep cascade of residual dense network (DC-RDN) was developed to reconstruct high-quality DW images from highly undersampled k-space data. Hyperpolarized 129Xe lung ventilation images were acquired from 101 participants and were retrospectively collected to generate synthetic DW-MRI data to train the DC-RDN. Afterwards, the performance of the DC-RDN was evaluated on retrospectively and prospectively undersampled multiple b-value 129Xe MRI datasets. RESULTS: Each slice with size of 64 × 64 × 5 could be reconstructed within 7.2 ms. For the retrospective test data, the DC-RDN showed significant improvement on all quantitative metrics compared with the conventional reconstruction methods (p < 0.05). The apparent diffusion coefficient (ADC) and morphometry parameters were not significantly different between the fully sampled and DC-RDN reconstructed images (p > 0.05). For the prospectively accelerated acquisition, the required breath-holding time was reduced from 17.8 to 4.7 s with an acceleration factor of 4. Meanwhile, the prospectively reconstructed results showed good agreement with the fully sampled images, with a mean difference of -0.72% and -0.74% regarding global mean ADC and mean linear intercept (Lm) values. CONCLUSIONS: DC-RDN is effective in accelerating multiple b-value gas DW-MRI while maintaining accurate estimation of lung microstructural morphometry, facilitating the clinical potential of studying lung diseases with hyperpolarized DW-MRI. KEY POINTS: • The deep cascade of residual dense network allowed fast and high-quality reconstruction of multiple b-value gas diffusion-weighted MRI at an acceleration factor of 4. • The apparent diffusion coefficient and morphometry parameters were not significantly different between the fully sampled images and the reconstructed results (p > 0.05). • The required breath-holding time was reduced from 17.8 to 4.7 s and each slice with size of 64 × 64 × 5 could be reconstructed within 7.2 ms.

DCE-MRI of esophageal carcinoma using star-VIBE compared with conventional 3D-VIBE.

To investigate the value of the star-VIBE sequence in dynamic contrast-enhanced magnetic resonance imaging of esophageal carcinoma under free breathing conditions. From February 2019 to June 2020, 60 patients with esophageal carcinoma were prospectively enrolled to undergo dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) with the K-space golden-angle radial stack-of-star acquisition scheme (star-VIBE) sequence (Group A) or conventional 3D volumetric-interpolated breath-hold examination (3D-VIBE) sequence (Group B), completely randomized grouping. The image quality of DCE-MRI was subjectively evaluated at five levels and objectively evaluated according to the image signal-to-noise ratio (SNR) and contrast-noise ratio (CNR). The DCE-MRI parameters of volume transfer constant (Ktrans), rate constant (Kep) and vascular extracellular volume fraction (Ve) were calculated using the standard Tofts double-compartment model in the post-perfusion treatment software TISSUE 4D (Siemens). Each group included 30 randomly selected cases. There was a significant difference in subjective classification between the groups (35.90 vs 25.10, p = 0.009). The study showed that both the SNR and CNR of group A were significantly higher than those of group B (p = 0.004 and < 0.001, respectively). There was no significant difference in Ktrans, Kep or Ve between the groups (all p > 0.05). The star-VIBE sequence can be applied in DCE-MRI examination of esophageal carcinoma, which can provide higher image quality than the conventional 3D-VIBE sequence in the free breathing state.

Damaged lung gas exchange function of discharged COVID-19 patients detected by hyperpolarized 129Xe MRI.

The recovery process of COVID-19 patients is unclear. Some recovered patients complain of continued shortness of breath. Vasculopathy has been reported in COVID-19, stressing the importance of probing pulmonary microstructure and function at the alveolar-capillary interface. While computed tomography (CT) detects structural abnormalities, little is known about the impact of disease on lung function. 129Xe magnetic resonance imaging (MRI) is a technique uniquely capable of assessing ventilation, microstructure, and gas exchange. Using 129Xe MRI, we found that COVID-19 patients show a higher rate of ventilation defects (5.9% versus 3.7%), unchanged microstructure, and longer gas-blood exchange time (43.5 ms versus 32.5 ms) compared with healthy individuals. These findings suggest that regional ventilation and alveolar airspace dimensions are relatively normal around the time of discharge, while gas-blood exchange function is diminished. This study establishes the feasibility of localized lung function measurements in COVID-19 patients and their potential usefulness as a supplement to structural imaging.

Comparison of comfort and complications in breast cancer patients of implantable venous access port (IVAP) with ultrasound guided internal jugular vein (IJV) and axillary vein/subclavian vein (AxV/SCV) puncture: a randomized controlled study protocol.

BACKGROUND: Internal jugular vein (IJV) and axillary vein/subclavian vein (AxV/SCV) are commonly used for implantable venous access port (IVAP) implantation in breast cancer (BC) patients with chemotherapy. Previous studies focused on complications between these different approaches and ignored patient comfort. In this study, we aim to compare patient comfort between IJV and AxV/SCV approaches, as well as surgery duration and complications. METHODS: This is a single-center prospective randomized controlled clinical trial. A total of 200 patients diagnosed with invasive BC will be enrolled in this study. After signing written informed consent, patients schedule to undergo IVAP implantation will be randomized at a 1:1 ratio to receive central venous catheters (CVC) with either IJV or AxV/SCV approaches. Baseline as well as demographic data and procedure time of port implantation will be recorded. All patients will receive assessment of comfort with a comfort scale table at days 1, 2 and 7 after implantation surgery. Patients will be followed up and complications will be recorded until devices are removed at the end of the treatment period, or in case of complications. Patient comfort, procedure time of implantation and complications will be compared and analyzed between these two arms. DISCUSSION: To the best of our knowledge, this is the first study to compare patient comfort as primary outcome measure between IJV and AxV/SCV puncture. This study will further confirm the benefits of ultrasound guidance and may provide a better choice of IVAP implantation for BC patients. TRIAL REGISTRATION: This study has been registered at Chinese Clinical Trial Registry (ChiCTR, www. chictr.org.cn) and Chinese Ethics Committee of Registering Clinical Trials (No. ChiCTR2000034986).

A laser metallurgy route for the batch preparation of mm-scale 3D silver/graphite heteronanoclusters in air.

We report a batch preparation of mm-scale 3D Ag hetero-nanoclusters which exhibit an excellent surface plasmon resonance ability via facile laser metallurgy. Under laser irradiation, the porous AgI-based coordination network crystals were instantly converted into 3D graphite-encapsulated Ag hetero-nanoclusters with uniform sizes and gaps in several seconds. The obtained hetero-nanoclusters exhibited superior 3D confocal laser energy utilization compared with the other 0D, 1D and 2D SERS substrates, solving the bottleneck caused by laser focusing deviation in the SERS active depth. The mass-produced SERS devices were ultra-sensitive for the detection of life and industrial organic pollutants in terms of low detection and enriched capacity.

Ultrasonographic Diagnosis of Lipomatosis of Nerve: A Review of Ultrasonographic Finding for 8 Cases.

OBJECTIVE: Lipomatosis of nerve (LN) is a rare tumor-like condition with epineural and perineural infiltration by adipose and fibrous tissue. The purpose was to analyze the ultrasonographic findings of LN involving upper limb peripheral nerves. METHODS: This was a retrospective analysis of a series of 8 patients with LN involving upper-limb peripheral nerves between 2013 and 2019. All patients underwent preoperative ultrasonography for the upper-extremity nerves and were diagnosed as LN by surgery. The clinical manifestations, ultrasonography characteristics, and accuracy were analyzed. RESULTS: In this series, LN was involved in 10 peripheral nerves from 8 patients. The median nerve was the most commonly affected nerve (60%). Four cases presented macrodactyly combined with masses from distal forearm and extending to wrist and palm areas. Among 8 patients, 5 cases were diagnosed with LN by preoperative ultrasonography, an accuracy of 62.5%. Axial ultrasonic imaging showed the punctate hypoechoic fascicles was embedded in hyperechoic adipose tissue in the "lotus root-like" appearance; longitudinal ultrasonic imaging showed the strip hypoechoic fascicles alternates with hyperechoic adipose tissue in the "cable-like" appearance. Meanwhile, ultrasonic imaging showed the thickened of adipose tissue around the affected nerve and the enlargement of flexor tendons in some patients. CONCLUSIONS: Ultrasonography has the potential to be a useful tool for the noninvasive examination of LN. The possibility of LN should be considered in patients with a mass in wrist and palm, macrodactyly, or syndactyly. Our finding may benefit the preoperative differential diagnosis with common nerve tumors.

Quantitative evaluation of lung injury caused by PM2.5 using hyperpolarized gas magnetic resonance.

PURPOSE: To demonstrate the feasibility of 129 Xe MR in evaluating the pulmonary physiological changes caused by PM2.5 in animal models. METHODS: Six rats were treated with PM2.5 solution (16.2 mg/kg) by intratracheal instillation twice a week for 4 weeks, and another six rats treated with normal saline served as the control cohort. Pulmonary function tests, hyperpolarized 129 Xe multi-b diffusion-weighted imaging, and chemical shift saturation recovery MR spectroscopy were performed on all rats, and the pulmonary structure and functional parameters were obtained from hyperpolarized 129 Xe MR data. Additionally, histological analysis was performed on all rats to evaluate alveolar septal thickness. Statistical analysis of all the obtained parameters was performed using unpaired 2-tailed t tests. RESULTS: Compared with the control group, the measured exchange time constant increased from 11.74 ± 2.39 to 14.00 ± 2.84 ms (P < .05), and the septal wall thickness increased from 6.17 ± 0.48 to 6.74 ± 0.52 µm (P < .05) in the PM2.5 cohort by 129 Xe MR spectroscopy, which correlated well with that obtained using quantitative histology (increased from 5.52 ± 0.32 to 6.20 ± 0.36 µm). Additionally, the mean TP/GAS ratio increased from 0.828 ± 0.115 to 1.019 ± 0.140 in the PM2.5 cohort (P = .021). CONCLUSIONS: Hyperpolarized 129 Xe MR could quantify the changes in gas exchange physiology caused by PM2.5 , indicating that the technique has the potential to be a useful tool for evaluation of pulmonary injury caused by air pollution in the future.

Fast and accurate reconstruction of human lung gas MRI with deep learning.

PURPOSE: To fast and accurately reconstruct human lung gas MRI from highly undersampled k-space using deep learning. METHODS: The scheme was comprised of coarse-to-fine nets (C-net and F-net). Zero-filling images from retrospectively undersampled k-space at an acceleration factor of 4 were used as input for C-net, and then output intermediate results which were fed into F-net. During training, a L2 loss function was adopted in C-net, while a function that united L2 loss with proton prior knowledge was used in F-net. The 871 hyperpolarized 129 Xe pulmonary ventilation images from 72 volunteers were randomly arranged as training (90%) and testing (10%) data. Ventilation defect percentage comparisons were implemented using a paired 2-tailed Student's t-test and correlation analysis. Furthermore, prospective acquisitions were demonstrated in 5 healthy subjects and 5 asymptomatic smokers. RESULTS: Each image with size of 96 × 84 could be reconstructed within 31 ms (mean absolute error was 4.35% and structural similarity was 0.7558). Compared with conventional compressed sensing MRI, the mean absolute error decreased by 17.92%, but the structural similarity increased by 6.33%. For ventilation defect percentage, there were no significant differences between the fully sampled and reconstructed images through the proposed algorithm (P = 0.932), but had significant correlations (r = 0.975; P < 0.001). The prospectively undersampled results validated a good agreement with fully sampled images, with no significant differences in ventilation defect percentage but significantly higher signal-to-noise ratio values. CONCLUSION: The proposed algorithm outperformed classical undersampling methods, paving the way for future use of deep learning in real-time and accurate reconstruction of gas MRI.

Single breath-hold measurement of pulmonary gas exchange and diffusion in humans with hyperpolarized 129 Xe MR.

Pulmonary diseases usually result in changes of the blood-gas exchange function in the early stages. Gas exchange across the respiratory membrane and gas diffusion in the alveoli can be quantified using hyperpolarized 129 Xe MR via chemical shift saturation recovery (CSSR) and diffusion-weighted imaging (DWI), respectively. Generally, CSSR and DWI data have been collected in separate breaths in humans. Unfortunately, the lung inflation level cannot be the exactly same in different breaths, which causes fluctuations in blood-gas exchange and pulmonary microstructure. Here we combine CSSR and DWI obtained with compressed sensing, to evaluate the gas diffusion and exchange function within a single breath-hold in humans. A new parameter, namely the perfusion factor of the respiratory membrane (SVRd/g ), is proposed to evaluate the gas exchange function. Hyperpolarized 129 Xe MR data are compared with pulmonary function tests and computed tomography examinations in healthy young, age-matched control, and chronic obstructive pulmonary disease human cohorts. SVRd/g decreases as the ventilation impairment and emphysema index increase. Our results indicate that the proposed method has the potential to detect the extent of lung parenchyma destruction caused by age and pulmonary diseases, and it would be useful in the early diagnosis of pulmonary diseases in clinical practice.

A Multiscale Fuzzy Metric for Detecting Small Infrared Targets Against Chaotic Cloudy/Sea-Sky Backgrounds.

In a low signal-to-clutter ratio (SCR) small-infrared-target image with chaotic cloudy-/sea-sky background, the target has very similar thermal intensities to the background (e.g., edges of clouds). In such case, how to accurately detect small targets is crucial in infrared search and tracking applications. Conventional methods based on the local difference/mutation potentially result in high miss and/or false alarm rates. Here, we propose an effective method for detecting small infrared targets embedded in complex backgrounds through a multiscale fuzzy metric that measures the certainty of targets in images. Accordingly, the detection task is formulated as a fuzzy measure issue. The presented metric is able to eliminate substantial background clutters and noise. Especially, it significantly improves SCR values of the image. Subsequently, a simple and adaptive threshold is used to segment target. Extensive clipped and real data experiments demonstrate that the proposed algorithm not only works more robustly for different target sizes, SCR values, target and/or background types, but also has better performance regarding detection accuracy, when compared with traditional baseline methods. Moreover, the mathematical proofs are provided for understanding the proposed detection method.

Highly and Adaptively Undersampling Pattern for Pulmonary Hyperpolarized 129Xe Dynamic MRI.

Hyperpolarized (HP) gas (e.g., 3He or 129Xe) dynamic MRI could visualize the lung ventilation process, which provides characteristics regarding lung physiology and pathophysiology. Compressed sensing (CS) is generally used to increase the temporal resolution of such dynamic MRI. Nevertheless, the acceleration factor of CS is constant, which results in difficulties in precisely observing and/or measuring dynamic ventilation process due to bifurcating network structure of the lung. Here, an adaptive strategy is proposed to highly undersample pulmonary HP dynamic k-space data, according to the characteristics of both lung structure and gas motion. After that, a valid reconstruction algorithm is developed to reconstruct dynamic MR images, considering the low-rank, global sparsity, gas-inflow effects, and joint sparsity. Both the simulation and the in vivo results verify that the proposed approach outperforms the state-of-the-art methods both in qualitative and quantitative comparisons. In particular, the proposed method acquires 33 frames within 6.67 s (more than double the temporal resolution of the recently proposed strategy), and achieves high-image quality [the improvements are 29.63%, 3.19%, 2.08%, and 13.03% regarding the mean absolute error (MAE), structural similarity index (SSIM), quality index based on local variance (QILV), and contrast-to-noise ratio (CNR) comparisons]. This provides accurate structural and functional information for early detection of obstructive lung diseases.