Degenerative Mitral Regurgitation Outcomes in Asian Compared With European-American Institutions.

Background: Clinical outcome and interventional thresholds for degenerative mitral regurgitation (DMR) were developed in studies of patients at European and American institutions (EAIs), but little is known about patients at Asian institutions (AsIs). Objectives: This study sought to contrast DMR presentation/management/outcomes of AsI patients vs EAI patients. Methods: Patients with DMR due to flail leaflet from Hong Kong and Singapore (AsI cohort, n = 737) were compared with EAI patients (n = 682) enrolled in the MIDA (Mitral regurgitation International Database) registry with similar eligibility criteria. Results: AsI patients presented similar DMR lesion/consequences vs EAI patients, but they were younger, with fewer symptoms (74% vs 44% Class I), more sinus rhythm (83% vs 69%), and lower EuroSCORE II (European System for Cardiac Operative Risk Evaluation II) (0.9 ± 0.5 vs 1.4 ± 1.5; all P < 0.0001). Imaging showed smaller absolute left atrial/ventricular dimensions in AsI patients, belying cardiac dilatation with larger body surface area-indexed diameters (all P < 0.01). Surgical/interventional mitral repair was similarly predominant (90% vs 91%; P = 0.47), and early repair was similarly beneficial (for AsI patients, adjusted HR: 0.28; 95% CI: 0.16-0.49; for EAI patients, HR: 0.32; 95% CI: 0.20-0.49; both P < 0.0001). However, AsI patients underwent fewer interventions (55% ± 2% vs 77% ± 2% at 1 year; P < 0.0001) and incurred excess mortality (adjusted HR: 1.60 [95% CI: 1.13-2.27] vs EAI patients; P = 0.008) at long-term postdiagnosis. Propensity score matching (434 patient pairs), which balanced all clinical characteristics, confirmed that there was undertreatment and excess mortality in the long term in AsI patients with DMR (P < 0.0001). Conclusions: Imaging may underestimate volume overload in AsI patients due to smaller cardiac cavities related to smaller body size compared with EAI patients with similar mitral lesions and DMR severity. AsI patients enjoy similar mitral repair predominance and early intervention benefits but undergo fewer mitral interventions than EAI patients and incur subsequent excess mortality, suggesting the need to account for imaging and cultural specificity to improve DMR outcomes worldwide.

Exploring the high-quality ingredients and mechanisms of Da Chuanxiong Formula in the treatment of neuropathic pain based on network pharmacology, molecular docking, and molecular dynamics simulation.

Da Chuanxiong Formula (DCXF) is a traditional herbal prescription used for pain management. It consists of Chuanxiong Rhizoma (CR) and Gastrodiae Rhizoma (GR). Despite its long history of use, the underlying therapeutic mechanism of DCXF remains insufficiently understood. Therefore, in this study, key target genes were obtained through network pharmacology research methods and molecular docking techniques, including transient receptor potential vanilloid 1 (TRPV1), adenosine A2a receptor (ADORA2A), nuclear receptor subfamily 3 group C member 1 (NR3C1), and protein kinase C beta (PRKCB). Molecular dynamics simulations demonstrated the favorable binding between all four key genes and their corresponding compounds. Notably, chronic constriction injury (CCI) treatment resulted in a significant decrease in mechanical threshold and thermal latency period for rat foot contraction, which was ameliorated upon administration of DCXF. Furthermore, real-time quantitative reverse transcription PCR (RT-qPCR) and western blot (WB) analyses indicated an upregulation of TRPV1, ADORA2A, NR3C1, and PRKCB expression in the rat dorsal root ganglion following CCI, which was attenuated by treatment with DCXF. The expressions of inflammatory factors, including tumor necrosis factor-α (TNF-α), interleukin 1 beta (IL-1ß), and interleukin 6 (IL-6), in the rat dorsal root ganglion were assessed using ELISA, confirming consistent trends with the aforementioned findings. The results of this study offer a promising theoretical foundation for the utilization of DCXF in the treatment of neuropathic pain (NP).

Combining catheter ablation and left atrial appendage occlusion in high-risk patients with atrial fibrillation: a propensity score-matched analysis.

BACKGROUND: The safety and efficacy of a combined approach of catheter ablation (CA) and left atrial appendage occlusion (LAAO) compared to LAAO alone remain unknown. METHODS: Patients with atrial fibrillation (AF) at increased stroke risk who underwent LAAO were divided into either combined (CA and LAAO) procedures or LAAO alone group. Propensity score matching was utilized to balance baseline characteristics. The primary endpoint of the study was a composite of death, thromboembolic events, major bleeding, heart failure (HF) rehospitalization, and major periprocedural complications. RESULTS: A total of 707 AF patients who underwent LAAO were included. After 1:1 propensity score matching, 166 patients who underwent LAAO alone (n = 83) or the combined procedure (n = 83) were analyzed. Successful LAAO was achieved in all (100%) patients, with a low incidence of periprocedural complications in both groups (2.4% vs. 4.8%, LAAO vs. combined, p = 0.68). The incidence of peri-device leak post-LAAO was significantly higher in the combined group (25.3% vs. 43.4%, p = 0.01). After a median follow-up of 2 years, there were no significant differences in the rates of the primary composite endpoint between the two strategies (22.2% vs. 14.3%, HR: 1.24 [95% CI: 0.51-2.97], p = 0.63). However, the rate of HF rehospitalization was significantly lower in the combined group (19.6% vs. 3.6%, HR: 4.89 [95% CI: 1.50-15.97], p = 0.024). CONCLUSIONS: Combining CA and LAAO in a "one-stop" approach is safe and brings additional benefits in relieving symptoms of heart failure, although peri-device leak was more common compared to LAAO alone.

Blue light photoreceptor cryptochrome 1 promotes wood formation and anthocyanin biosynthesis in Populus.

Blue light photoreceptor cryptochrome 1 (CRY1) in herbaceous plants plays crucial roles in various developmental processes, including cotyledon expansion, hypocotyl elongation and anthocyanin biosynthesis. However, the function of CRY1 in perennial trees is unclear. In this study, we identified two ortholog genes of CRY1 (PagCRY1a and PagCRY1b) from Populus, which displayed high sequence similarity to Arabidopsis CRY1. Overexpression of PagCRY1 substantially inhibited plant growth and promoted secondary xylem development in Populus, while CRISPR/Cas9-mediated knockout of PagCRY1 enhanced plant growth and delayed secondary xylem development. Moreover, overexpression of PagCRY1 dramatically increased anthocyanin accumulation. The further analysis supported that PagCRY1 functions specifically in response to blue light. Taken together, our results demonstrated that modulating the expression of blue light photoreceptor CRY1 ortholog gene in Populus could significantly influence plant biomass production and the process of wood formation, laying a foundation for further investigating the light-regulated tree growth.

The m6A methylation and expression profiles of mouse neural stem cells after hypoxia/reoxygenation.

BACKGROUND: Ischemia-reperfusion injury to the central nervous system often causes severe complications. The activation of endogenous neural stem cells (NSCs) is considered a promising therapeutic strategy for nerve repair. However, the specific biological processes and molecular mechanisms of NSC activation remain unclear, and the role of N6-methyladenosine (m6A) methylation modification in this process has not been explored. METHODS: NSCs were subjected to hypoxia/reoxygenation (H/R) to simulate ischemia-reperfusion in vivo. m6A RNA methylation quantitative kit was used to measure the total RNA m6A methylation level. Quantitative real-time PCR was used to detect methyltransferase and demethylase mRNA expression levels. Methylated RNA immunoprecipitation sequencing (MeRIP-seq) and RNA sequencing (RNA-seq) were conducted for NSCs in control and H/R groups, and the sequencing results were analyzed using bioinformatics. Finally, the migration ability of NSCs was identified by wound healing assays, and the proliferative capacity of NSCs was assessed using the cell counting kit-8, EdU assays and cell spheroidization assays. RESULTS: Overall of m6A modification level and Mettl14 mRNA expression increased in NSCs after H/R treatment. The m6A methylation and expression profiles of mRNAs in NSCs after H/R are described for the first time. Through the joint analysis of MeRIP-seq and RNA-seq results, we verified the proliferation of NSCs after H/R, which was regulated by m6A methylation modification. Seven hub genes were identified to play key roles in the regulatory process. Knockdown of Mettl14 significantly inhibited the proliferation of NSCs. In addition, separate analysis of the MeRIP-seq results suggested that m6A methylation regulates cell migration and differentiation in ways other than affecting mRNA expression. Subsequent experiments confirmed the migration ability of NSCs was suppressed by knockdown of Mettl14. CONCLUSION: The biological behaviors of NSCs after H/R are closely related to m6A methylation of mRNAs, and Mettl14 was confirmed to be involved in cell proliferation and migration.

A novel Recjf Exo signal amplification strategy based on bioinformatics-assisted truncated aptamer for efficient fluorescence detection of AFB1.

Aflatoxin B1 (AFB1) is a typical mycotoxin that signifacntly endangers public health and economy. In this study, we systematically studied the interaction of aptamers with AFB1 using circular dichroism, molecular dynamics, molecular docking, and fluorescence analysis. The truncated sequence aptamers were screened using molecular docking. We successfully obtained the AFB1 aptamer with higher affinity and its truncated form was enhanced by 5.2-fold compared to the initial AFB1 aptamer. In addition, for rapid detection of AFB1, we designed a fluorescent nano-adaptor sensing platform using RecJf exonuclease signal amplification strategy based on the optimal aptamer. The aptasensor showed satisfactory sensitivity towards AFB1 with a linear detection range of 1-400 ng/mL and a detection limit of 0.57 ng/mL. The aptasensor was successfully applied to the determination of AFB1 in soybean oil and corn oil with recoveries of 91.02 %-106.59 % and 87.39 %-110.61 %, respectively. The successful application of the AFB1 aptasensor, developed through bioinformatics truncation of the aptamer, provides a novel approach to creating a cost-effective, eco-friendly, and rapid aptamer sensing platform.

Echocardiographic Imaging in Transcatheter Structural Intervention: An AAE Review Paper.

Transcatheter structural heart intervention (TSHI) has gained popularity over the past decade as a means of cardiac intervention in patients with prohibitive surgical risks. Following the exponential rise in cases and devices developed over the period, there has been increased focus on developing the role of "structural imagers" amongst cardiologists. This review, as part of a growing initiative to develop the field of interventional echocardiography, aims to highlight the role of echocardiography in myriad TSHIs available within Asia. We first discuss the various echocardiography-based imaging modalities, including 3-dimensional echocardiography, fusion imaging, and intracardiac echocardiography. We then highlight a selected list of structural interventions available in the region-a combination of established interventions alongside novel approaches-describing key anatomic and pathologic characteristics related to the relevant structural heart diseases, before delving into various aspects of echocardiography imaging for each TSHI.

Left atrial appendage angiography for stroke risk prediction in patients with atrial fibrillation.

BACKGROUND: The current risk stratification schemes for stroke in patients with atrial fibrillation (AF) are insufficient for an accurate assessment of stroke risk. AIMS: This study evaluates the association between the mechanical function of the left atrial appendage (LAA), as assessed by angiography, and the risk of stroke. METHODS: We conducted a cross-sectional study to assess the mechanical function of the LAA by measuring the left atrial appendage ejection fraction (LAAEF) and grading the contrast retention (CR) using angiography. RESULTS: A total of 746 patients referred for a left atrial appendage occlusion (LAAO) procedure with (n=151; stroke group) or without (n=595; control group) a history of stroke were included in the analysis. LAAEF was significantly lower (14% [9-19] vs 20% [12-33]; p<0.001) and grade 3 CR was more common (66.9% vs 33.9%; p<0.001) in patients with a history of stroke. Multivariable analysis showed that CR was independently associated with stroke in patients with AF (grade 2 vs grade 1=7.29; 95% confidence interval [CI]: 2.84-21.65; p<0.001; grade 3 vs grade 1=16.45; 95% CI: 6.16-51.02; p<0.001). The receiver operating characteristics curve demonstrated that CR identified patients with stroke more accurately than the CHA2D-VASc score (C-statistic 0.712 vs 0.512; p<0.001), and the combination of CR and the CHA2DS2-VASc score provided the best performance (C-statistic 0.871 vs 0.829 [CHA2DS2-VASc score alone]; p=0.048) Conclusions: Impaired mechanical function of the LAA, indicated by a low LAAEF and CR, is associated with a history of stroke in patients with AF. Assessment of CR using LAA angiography helps improve the stratification scheme for stroke risk prediction.

Single-Walled Carbon Nanohorn-Based Fluorescence Energy Resonance Transfer Aptasensor Platform for the Detection of Aflatoxin B1.

Aflatoxin B1 (AFB1) is one of the most contaminated fungal toxins worldwide and is prone to cause serious economic losses, food insecurity, and health hazards to humans. The rapid, on-site, and economical method for AFB1 detection is need of the day. In this study, an AFB1 aptamer (AFB1-Apt) sensing platform was established for the detection of AFB1. Fluorescent moiety (FAM)-modified aptamers were used for fluorescence response and quenching, based on the adsorption quenching function of single-walled carbon nanohorns (SWCNHs). Basically, in our constructed sensing platform, the AFB1 specifically binds to AFB1-Apt, making a stable complex. This complex with fluorophore resists to be adsorbed by SWCNHs, thus prevent SWCNHs from quenching of fluorscence, resulting in a fluorescence response. This designed sensing strategy was highly selective with a good linear response in the range of 10-100 ng/mL and a low detection limit of 4.1 ng/mL. The practicality of this sensing strategy was verified by using successful spiking experiments on real samples of soybean oil and comparison with the enzyme-linked immunosorbent assay (ELISA) method.

Advances in aptamers, and application of mycotoxins detection: A review.

Mycotoxin contamination in food products can easily cause serious health hazards and economic losses to human beings. How to accurately detect and effectively control mycotoxin contamination has become a global concern. Mycotoxins conventional detection techniques e.g; ELISA, HPLC, have limitations like, low sensitivity, high cost and time-consuming. Aptamer-based biosensing technology has the advantages of high sensitivity, high specificity, wide linear range, high feasibility, and non-destructiveness, which overcomes the shortcomings of conventional analysis techniques. This review summarizes the sequences of mycotoxin aptamers that have been reported so far. Based on the application of four classic POST-SELEX strategies, it also discusses the bioinformatics-assisted POST-SELEX technology in obtaining optimal aptamers. Furthermore, trends in the study of aptamer sequences and their binding mechanisms to targets is also discussed. The latest examples of aptasensor detection of mycotoxins are classified and summarized in detail. Newly developed dual-signal detection, dual-channel detection, multi-target detection and some types of single-signal detection combined with unique strategies or novel materials in recent years are focused. Finally, the challenges and prospects of aptamer sensors in the detection of mycotoxins are discussed. The development of aptamer biosensing technology provides a new approach with multiple advantages for on-site detection of mycotoxins. Although aptamer biosensing shows great development potential, still some challenges and difficulties are there in practical applications. Future research need high focus on the practical applications of aptasensors and the development of convenient and highly automated aptamers. This may lead to the transition of aptamer biosensing technology from laboratory to commercialization.

miR-872-5p/FOXO3a/Wnt signaling feed-forward loop promotes proliferation of endogenous neural stem cells after spinal cord ischemia-reperfusion injury in rats.

The activation of endogenous neural stem cells (NSCs) is considered an important mechanism of neural repair after mechanical spinal cord injury; however, whether endogenous NSC proliferation can also occur after spinal cord ischemia-reperfusion injury (SCIRI) remains unclear. In this study, we aimed to verify the existence of endogenous NSC proliferation after SCIRI and explore the underlying molecular mechanism. NSC proliferation was observed after SCIRI in vivo and oxygen-glucose deprivation and reperfusion (OGD/R) in vitro, accompanied by a decrease in forkhead box protein O 3a (FOXO3a) expression. This downward trend was regulated by the increased expression of microRNA-872-5p (miR-872-5p). miR-872-5p affected NSC proliferation by targeting FOXO3a to increase the expression of ß-catenin and T-cell factor 4 (TCF4). In addition, TCF4 in turn acted as a transcription factor to increase the expression level of miR-872-5p, and knockdown of FOXO3a enhanced the binding of TCF4 to the miR-872-5p promoter. In conclusion, SCIRI in vivo and OGD/R in vitro stimulated the miR-872-5p/FOXO3a/ß-catenin-TCF4 pathway, thereby promoting NSC proliferation. At the same time, FOXO3a affected TCF4 transcription factor activity and miR-872-5p expression, forming a positive feedback loop that promotes NSC proliferation.

A Tale of Two: When Neural Stem Cells Encounter Hypoxia.

Normoxia is defined as an oxygen concentration of 20.9%, as in room air, whereas hypoxia refers to any oxygen concentration less than this. Any physiological oxygen deficiency or tissue oxygen deficiency relative to demand is called hypoxia. Neural stem cells (NSCs) are multipotent stem cells that can differentiate into multiple cell lines such as neurons, oligodendrocytes, and astrocytes. Under hypoxic conditions, the apoptosis rate of NSCs increases remarkably in vitro or in vivo. However, some hypoxia promotes the proliferation and differentiation of NSCs. The difference is related to the oxygen concentration, the duration of hypoxia, the hypoxia tolerance threshold of the NSCs, and the tissue source of the NSCs. The main mechanism of hypoxia-induced proliferation and differentiation involves an increase in cyclin and erythropoietin concentrations, and hypoxia-inducible factors play a key role. Multiple molecular pathways are activated during hypoxia, including Notch, Wnt/ß-catenin, PI3K/Akt, and altered microRNA expression. In addition, we review the protective effect of exogenous NSCs transplantation on ischemic or anoxic organs, the therapeutic potential of hypoxic preconditioning on exogenous NSCs and clinical application of NSCs.

Complete region of interest reconstruction by fusing multiview deformable three-dimensional transesophageal echocardiography images.

BACKGROUND: While three-dimensional transesophageal echocardiography (3D TEE) has been increasingly used for assessing cardiac anatomy and function, it still suffers from a limited field of view (FoV) of the ultrasound transducer. Therefore, it is difficult to examine a complete region of interest without moving the transducer. Existing methods extend the FoV of 3D TEE images by mosaicing multiview static images, which requires synchronization between 3D TEE images and electrocardiogram (ECG) signal to avoid deformations in the images and can only get the widened image at a specific phase. PURPOSE: This work aims to develop a novel multiview nonrigid registration and fusion method to extend the FoV of 3D TEE images at different cardiac phases, avoiding the bias toward the specifically chosen phase. METHODS: A multiview nonrigid registration and fusion method is proposed to enlarge the FoV of 3D TEE images by fusing dynamic images captured from different viewpoints sequentially. The deformation field for registering images is defined by a collection of affine transformations organized in a graph structure and is estimated by a direct (intensity-based) method. The accuracy of the proposed method is evaluated by comparing it with two B-spline-based methods, two Demons-based methods, and one learning-based method VoxelMorph. Twenty-nine sequences of in vivo 3D TEE images captured from four patients are used for the comparative experiments. Four performance metrics including checkerboard volumes, signed distance, mean absolute distance (MAD), and Dice similarity coefficient (DSC) are used jointly to evaluate the accuracy of the results. Additionally, paired t-tests are performed to examine the significance of the results. RESULTS: The qualitative results show that the proposed method can align images more accurately and obtain the fused images with higher quality than the other five methods. Additionally, in the evaluation of the segmented left atrium (LA) walls for the pairwise registration and sequential fusion experiments, the proposed method achieves the MAD of (0.07 ± 0.03) mm for pairwise registration and (0.19 ± 0.02) mm for sequential fusion. Paired t-tests indicate that the results obtained from the proposed method are more accurate than those obtained by the state-of-the-art VoxelMorph and the diffeomorphic Demons methods at the significance level of 0.05. In the evaluation of left ventricle (LV) segmentations for the sequential fusion experiments, the proposed method achieves a DSC of (0.88 ± 0.08), which is also significantly better than diffeomorphic Demons at the 0.05 level. The FoVs of the final fused 3D TEE images obtained by our method are enlarged around two times compared with the original images. CONCLUSIONS: Without selecting the static (ECG-gated) images from the same cardiac phase, this work addressed the problem of limited FoV of 3D TEE images in the deformable scenario, obtaining the fused images with high accuracy and good quality. The proposed method could provide an alternative to the conventional fusion methods that are biased toward the specifically chosen phase.

Fragmented Vortex in Heart Failure With Reduced Ejection Fraction: A Prospective Vector Flow Mapping Study.

OBJECTIVE: Heart failure with reduced ejection fraction (HFrEF) is associated with structural and functional left ventricular changes. We compared intracardiac vortices between patients with HFrEF and normal participants using echocardiographic vector flow mapping, a novel intracardiac vortex analysis technology. METHODS: Transthoracic echocardiography was performed on 20 patients with HFrEF (age: 61 ± 15 y, 15 men) and 20 normal participants (age: 59 ± 12 y, 12 men) age- and sex-balanced at the cohort level. Systolic and diastolic energy loss, area (indexed by left ventricular end-diastolic diameter), circulation (reflects vortex strength) and relative positions of the largest vortex during systole (S-vortex), early (E-vortex) and late (A-vortex) diastole and maximal number of vortices in a single frame (MNV) were assessed. DISCUSSION: Patients with HFrEF had disproportionately sized vortices with smaller indexed vortex areas (p < 0.0001), and more fragmented vortices with higher MNV during both systole (p = 0.030) and diastole (p < 0.0001). These accompanied higher diastolic energy loss (p = 0.001). Additionally, the E-vortex (p = 0.002) and A-vortex (p < 0.0001) were more apically positioned, and the S-vortex was weaker (p = 0.033) in patients with HFrEF. More severe fragmentation (higher MNV) correlated with worse energy efficiency (higher energy loss). CONCLUSION: Patients with HFrEF had more fragmented intracardiac vortices and lower energy efficiency predominantly during diastole.

Organic acids metabolism and GABA shunt involved in maintaining quality of Malus domestica by methyl jasmonate treatment.

Apples (cv. Golden Delicious) were used as the materials to investigate methyl jasmonate (MeJA) dipping on quality parameters, organic acids metabolism and GABA shunt during storage at 21 ± 1 °C and 75 ± 5 % relative humidity. Results demonstrated that MeJA treatment reduced mass loss, respiratory intensity and ethylene release, and maintained higher flesh firmness and soluble solid content of apples. MeJA also decreased malic acid content, increased succinic and tartaric acids contents, and inhibited cytoplasmic aconitase (Cyt-ACO), NADP-malate (NADP-ME), phosphoenolpyruvate dehydrogenase (PEPC), mitochondrial citrate synthase (Mit-CS), glutamate dehydrogenase (GAD), and GABA transferase (GABA-T) activities in apples. NADP-isocitrate dehydrogenase (NADP-IDH), mitochondrial cis-aconitase (Mit-ACO), and cytoplasmic NAD-malate dehydrogenase (CytNAD-MDH) activities in apples were also enhanced by MeJA dipping. Moreover, MeJA dipping enhanced MdCytNAD-MDH and MdNADP-IDH expressions, and down-regulated MdGAD, MdGABA-T, MdNADP-ME, MdPEPC, MdCyt-ACO and MdMit-CS expressions in apples. These results suggest that MeJA dipping can maintain storage quality of "Golden Delicious" apples by regulating organic acids metabolism and GABA shunt.

Trehalose Regulates Starch, Sorbitol, and Energy Metabolism to Enhance Tolerance to Blue Mold of "Golden Delicious" Apple Fruit.

The efficacy of trehalose on the lesion diameter of apples (cv. Golden Delicious) inoculated with Penicillium expansum was evaluated to screen the optimal concentration. The changes in gene expression and activity of the enzyme in starch, sorbitol, and energy metabolism were also investigated in apples after trehalose treatment. The results revealed that trehalose dipping reduced the lesion diameter of apples inoculated with P. expansum. Trehalose suppressed the activities and gene expressions of ß-amylase, NAD-sorbitol dehydrogenase, and NADP-sorbitol dehydrogenase, whereas it decreased the sorbitol 6-phosphate dehydrogenase gene expression and amylose, amylopectin, total starch, and reducing sugar contents. Additionally, trehalose improved the gene expressions and activities of α-amylase, starch-branching enzymes, total amylase, H+-ATPase, and Ca2+-ATPase, as well as soluble sugar, adenosine triphosphate, and adenosine diphosphate contents and energy charge in apples. These findings imply that trehalose could induce tolerance to the blue mold of apple fruit by regulating starch, sorbitol, and energy metabolism.

Advances in Procedural Echocardiographic Imaging in Transcatheter Edge-to-Edge Repair for Mitral Regurgitation.

Transcatheter edge-to-edge repair (TEER) therapy is recommended by the American College of Cardiology/American Heart Association (ACC/AHA) guidelines for selected patients with symptomatic severe or moderate-severe mitral regurgitation (MR). Echocardiography, in particular transesophageal echocardiography (TEE), plays a critical role in procedural planning and guidance for TEER. Recent innovations and advances in TEE techniques including three-dimensional (3D) imaging, unlimited x-plane imaging, live 3D multiplanar reconstruction, as well as transillumination imaging with color Doppler and transparency rendering have further enhanced procedural imaging for TEER, especially for complex diseases including commissural defects, clefts, and multi-segment pathologies. This review discusses the technology of these advanced procedural imaging techniques and provides a "step-by-step" guide on how to apply them during the TEER procedure with a focus on their added values in treatment of complex valve lesions.

Characterization of GABA-Transaminase Gene from Mulberry (Morus multicaulis) and Its Role in Salt Stress Tolerance.

Gamma-aminobutyric acid (GABA) has been reported to accumulate in plants when subjected to salt stress, and GABA-transaminase (GABA-T) is the main GABA-degrading enzyme in the GABA shunt pathway. So far, the salt tolerance mechanism of the GABA-T gene behind the GABA metabolism remains unclear. In this study, the cDNA (designated MuGABA-T) of GABA-T gene was cloned from mulberry, and our data showed that MuGABA-T protein shares some conserved characteristics with its homologs from several plant species. MuGABA-T gene was constitutively expressed at different levels in mulberry tissues, and was induced substantially by NaCl, ABA and SA. In addition, our results demonstrated that exogenous application of GABA significantly reduced the salt damage index and increased plant resistance to NaCl stress. We further performed a functional analysis of MuGABA-T gene and demonstrated that the content of GABA was reduced in the transgenic MuGABA-T Arabidopsis plants, which accumulated more ROS and exhibited more sensitivity to salt stress than wild-type plants. However, exogenous application of GABA significantly increased the activities of antioxidant enzymes and alleviated the active oxygen-related injury of the transgenic plants under NaCl stress. Moreover, the MuGABA-T gene was overexpressed in the mulberry hairy roots, and similar results were obtained for sensitivity to salt stress in the transgenic mulberry plants. Our results suggest that the MuGABA-T gene plays a pivotal role in GABA catabolism and is responsible for a decrease in salt tolerance, and it may be involved in the ROS pathway in the response to salt stress. Taken together, the information provided here is helpful for further analysis of the function of GABA-T genes, and may promote mulberry resistance breeding in the future.