Single-cell RNA combined with bulk RNA analysis to explore oxidative stress and energy metabolism factors and found a new prostate cancer oncogene MXRA8.

BACKGROUND: Prostate cancer is the most common malignancy among men worldwide, and its diagnosis and treatment are challenging due to its heterogeneity. METHODS: Integrating single-cell RNA sequencing (scRNA-seq) and bulk RNA-seq data, we identified two molecular subtypes of prostate cancer based on dysregulated genes involved in oxidative stress and energy metabolism. We constructed a risk score model (OMR) using common differentially expressed genes, which effectively evaluated prostate cancer prognosis. RESULTS: Our analysis demonstrated a significant correlation between the risk score model and various factors, including tumor immune microenvironment, genomic variations, chemotherapy resistance, and immune response. Notably, patients with low-risk scores exhibited increased sensitivity to chemotherapy and immunotherapy compared to those with high-risk scores, indicating the model's potential to predict patient response to treatment. Additionally, our investigation of MXRA8 in prostate cancer showed significant upregulation of this gene in the disease as confirmed by PCR and immunohistochemistry. Functional assays including CCK-8, transwell, plate cloning, and ROS generation assay demonstrated that depletion of MXRA8 reduced the proliferative, invasive, migratory capabilities of PC-3 cells, as well as their ROS generation capacity. CONCLUSIONS: Our study highlights the potential of oxidative stress and energy metabolism-related genes as prognostic markers and therapeutic targets in prostate cancer. The integration of scRNA-seq and bulk RNA-seq data enables a better understanding of prostate cancer heterogeneity and promotes personalized treatment development. Additionally, we identified a novel oncogene MXRA8 in prostate cancer.

High fat diet-induced downregulation of TRPV2 mediates hepatic steatosis via p21 signalling

The global prevalence and incidence of non-alcoholic fatty liver disease (NAFLD) are exhibiting an increasing trend. NAFLD is characterized by a significant accumulation of lipids, though its underlying mechanism is still unknown. Here we report that high-fat diet (HFD) feeding induced hepatic steatosis in mice, which was accompanied by a reduction in the expression and function of hepatic TRPV2. Moreover, conditional knockout of TRPV2 in hepatocytes exacerbated HFD-induced hepatic steatosis. In an in vitro model of NAFLD, TRPV2 regulated lipid accumulation in HepG2 cells, and TRPV2 activation inhibited the expression of the cellular senescence markers p21 and p16, all of which were mediated by AMPK phosphorylation. Finally, we found that administration of probenecid, a TRPV2 agonist, impaired HFD-induced hepatic steatosis and suppressed HFD-induced elevation in p21 and p16. Collectively, our findings imply that hepatic TRPV2 protects against the accumulation of lipids by modulating p21 signalling. (AU)

High fat diet-induced downregulation of TRPV2 mediates hepatic steatosis via p21 signalling

The global prevalence and incidence of non-alcoholic fatty liver disease (NAFLD) are exhibiting an increasing trend. NAFLD is characterized by a significant accumulation of lipids, though its underlying mechanism is still unknown. Here we report that high-fat diet (HFD) feeding induced hepatic steatosis in mice, which was accompanied by a reduction in the expression and function of hepatic TRPV2. Moreover, conditional knockout of TRPV2 in hepatocytes exacerbated HFD-induced hepatic steatosis. In an in vitro model of NAFLD, TRPV2 regulated lipid accumulation in HepG2 cells, and TRPV2 activation inhibited the expression of the cellular senescence markers p21 and p16, all of which were mediated by AMPK phosphorylation. Finally, we found that administration of probenecid, a TRPV2 agonist, impaired HFD-induced hepatic steatosis and suppressed HFD-induced elevation in p21 and p16. Collectively, our findings imply that hepatic TRPV2 protects against the accumulation of lipids by modulating p21 signalling. (AU)

Icaritin greatly attenuates ß-amyloid-induced toxicity in vivo.

AIMS: The accumulation and deposition of ß-amyloid (Aß) has always been considered a major pathological feature of Alzheimer's disease (AD). The latest and mainstream amyloid cascade hypothesis indicates that all the main pathological changes in AD are attributed to the accumulation of soluble Aß. However, the exploration of therapeutic drugs for Aß toxicity has progressed slowly. This study aims to investigate the protective effects of Icaritin on the Aß-induced Drosophila AD model and its possible mechanism. METHODS: To identify the effects of Icaritin on AD, we constructed an excellent Drosophila AD model named Aßarc (arctic mutant Aß42) Drosophila. Climbing ability, flight ability, and longevity were used to evaluate the effects of Icaritin on AD phenotypes. Aßarc was determined by immunostaining and ELISA. To identify the effects of Icaritin on oxidative stress, we performed the detection of ROS, hydrogen peroxide, MDA, SOD, catalase, GST, and Caspase-3. To identify the effects of Icaritin on energy metabolism, we performed the detection of ATP and lactate. Transcriptome analysis and qRT-PCR verifications were used to detect the genes directly involved in oxidative stress and energy metabolism. Mitochondrial structure and function were detected by an electron microscopy assay, a mitochondrial membrane potential assay, and a mitochondrial respiration assay. RESULTS: We discovered that Icaritin almost completely rescues the climbing ability, flight ability, and longevity of Aßarc Drosophila. Aßarc was dramatically reduced by Icaritin treatment. We also found that Icaritin significantly reduces oxidative stress and greatly improves impaired energy metabolism. Importantly, transcriptome analysis and qRT-PCR verifications showed that many key genes, directly involved in oxidative stress and energy metabolism, are restored by Icaritin. Next, we found that Icaritin perfectly restores the integrity of mitochondrial structure and function damaged by Aßarc toxicity. CONCLUSION: This study suggested that Icaritin is a potential drug to deal with the toxicity of Aßarc, at least partially realized by restoring the mitochondria/oxidative stress/energy metabolism axis, and holds potential for translation to human AD.

NcRNAs: A synergistically antiapoptosis therapeutic tool in Alzheimer's disease.

AIMS: The aim of this review is to systematically summarize and analyze the noncoding RNAs (ncRNAs), especially microRNAs (miRNAs), long noncoding RNAs (lncRNAs), and circular RNAs (circRNAs), in the cell apoptosis among Alzheimer's disease (AD) in recent years to demonstrate their value in the diagnosis and treatment of AD. METHODS: We systematically summarized in vitro and in vivo studies focusing on the ncRNAs in the regulation of cell apoptosis among AD in PubMed, ScienceDirect, and Google Scholar. RESULTS: We discover three patterns of ncRNAs (including 'miRNA-mRNA', 'lncRNA-miRNA-mRNA', and 'circRNA-miRNA-mRNA') form the ncRNA-based regulatory networks in regulating cell apoptosis in AD. CONCLUSIONS: This review provides a future diagnosis and treatment strategy for AD patients based on ncRNAs.

High fat diet-induced downregulation of TRPV2 mediates hepatic steatosis via p21 signalling.

The global prevalence and incidence of non-alcoholic fatty liver disease (NAFLD) are exhibiting an increasing trend. NAFLD is characterized by a significant accumulation of lipids, though its underlying mechanism is still unknown. Here we report that high-fat diet (HFD) feeding induced hepatic steatosis in mice, which was accompanied by a reduction in the expression and function of hepatic TRPV2. Moreover, conditional knockout of TRPV2 in hepatocytes exacerbated HFD-induced hepatic steatosis. In an in vitro model of NAFLD, TRPV2 regulated lipid accumulation in HepG2 cells, and TRPV2 activation inhibited the expression of the cellular senescence markers p21 and p16, all of which were mediated by AMPK phosphorylation. Finally, we found that administration of probenecid, a TRPV2 agonist, impaired HFD-induced hepatic steatosis and suppressed HFD-induced elevation in p21 and p16. Collectively, our findings imply that hepatic TRPV2 protects against the accumulation of lipids by modulating p21 signalling.

Leveraging diverse cell-death related signature predicts the prognosis and immunotherapy response in renal clear cell carcinoma.

Background: Modulation of programmed cell death in tumor cells alters the tumor microenvironment and the influx of tumor-infiltrating lymphocytes, and the combination of its inducers and immune checkpoint inhibitors plays a synergistic role in enhancing antitumor effects. Methods: We downloaded the data of clear cell renal cell carcinoma samples from The Cancer Genome Atlas and used a machine learning approach to build a new programmed cell death index (PCDI) through 13 programmed cell death-related genes. Based on PCDI, clinical features, tumor immune microenvironment, chemotherapy response and immunotherapy response were systematically analyzed. Results: PCDI consists of eight programmed cell death-related genes (TBX3, BID, TCIRG1, IDUA, KDR, PYCARD, IFNG and LRRK2). PCDI is a reliable predictor of survival in clear cell renal cell carcinoma patients and has been validated in multiple external datasets. We found that the high PCDI group showed higher levels of immune cell infiltration and better response to immunotherapy compared to the low PCDI group, and PCDI can also be used for prognostic prediction in a variety of cancers other than clear cell renal cell carcinoma. In vitro experiments demonstrated that knockdown of IDUA inhibited the proliferation and migration of clear cell renal cell carcinoma. Conclusions: The PCDI identified in this study provides valuable insights into the clinical management of clear cell renal cell carcinoma by accurately evaluating the prognosis of patients with clear cell renal carcinoma and identifying the patient population that would benefit from immunotherapy.

Whole-Body Dynamics-Based Aerial Fall Trajectory Optimization and Landing Control for Humanoid Robot.

When humanoid robots work in human environments, falls are inevitable due to the complexity of such environments. Current research on humanoid robot falls has mainly focused on falls on the ground, with little research on humanoid robots falling from the air. In this paper, we employ an extended state variable formulation that directly maps from the high-level motion strategy space to the full-body joint space to optimize the falling trajectory in order to protect the robot when falling from the air. In order to mitigate the impact force generated by the robot's fall, during the aerial phase, we employ simple proportion differentiation (PD) control. In the landing phase, we optimize the optimal contact force at the contact point using the centroidal dynamics model. Based on the contact force, the changes to the end-effector positions are solved using a dual spring-damper model. In the simulation experiments, we conduct three comparative experiments, and the simulation results demonstrate that the robot can safely fall 1.5 m from the ground at a pitch angle of 45°. Finally, we experimentally validate the methods on an actual robot by performing a side-fall experiment. The experimental results show that the proposed trajectory optimization and motion control methods can provide excellent shock absorption for the impact generated when a robot falls.

Tubular injury in diabetic kidney disease: molecular mechanisms and potential therapeutic perspectives.

Diabetic kidney disease (DKD) is a chronic complication of diabetes and the leading cause of end-stage renal disease (ESRD) worldwide. Currently, there are limited therapeutic drugs available for DKD. While previous research has primarily focused on glomerular injury, recent studies have increasingly emphasized the role of renal tubular injury in the pathogenesis of DKD. Various factors, including hyperglycemia, lipid accumulation, oxidative stress, hypoxia, RAAS, ER stress, inflammation, EMT and programmed cell death, have been shown to induce renal tubular injury and contribute to the progression of DKD. Additionally, traditional hypoglycemic drugs, anti-inflammation therapies, anti-senescence therapies, mineralocorticoid receptor antagonists, and stem cell therapies have demonstrated their potential to alleviate renal tubular injury in DKD. This review will provide insights into the latest research on the mechanisms and treatments of renal tubular injury in DKD.

Soil water content and nitrogen differentially correlate with multidimensional leaf traits of two temperate broadleaf species.

The variation and correlation of leaf economics and vein traits are crucial for predicting plant ecological strategies under different environmental changes. However, correlations between these two suites of traits and abiotic factors such as soil water and nitrogen content remain ambiguous. We measured leaf economics and vein traits as well as soil water and nitrogen content for two different shade-tolerant species (Betula platyphylla and Acer mono) in four mixed broadleaved-Korean pine (Pinus koraiensis) forests along a latitudinal gradient in Northeast China. We found that leaf economics traits and vein traits were decoupled in shade-intolerant species, Betula platphylla, but significantly coupled in a shade-tolerant species, A. mono. We found stronger correlations among leaf traits in the shade tolerant species than in the shade intolerant species. Furthermore, leaf economic traits were positively correlated with the soil water gradient for both species, whereas vein traits were positively correlated with soil water gradient for the shade intolerant species but negatively correlated in the shade tolerant species. Although economic traits were positively correlated with soil nitrogen gradient in shade intolerant species but not correlated in shade tolerant species, vein traits were negatively correlated with soil nitrogen gradient in shade tolerant species but not correlated in shade intolerant species. Our study provides evidence for distinct correlations between leaf economics and vein traits and local abiotic factors of species differing in light demands. We recommend that the ecological significance of shade tolerance be considered for species when evaluating ecosystem functions and predicting plant responses to environmental changes.

DOPAnization of tyrosine in α-synuclein by tyrosine hydroxylase leads to the formation of oligomers.

Parkinson's disease is a progressive neurodegenerative disorder characterized by the preferential loss of tyrosine hydroxylase (TH)-expressing dopaminergic neurons in the substantia nigra. Although the abnormal accumulation and aggregation of α-synuclein have been implicated in the pathogenesis of Parkinson's disease, the underlying mechanisms remain largely elusive. Here, we found that TH converts Tyr136 in α-synuclein into dihydroxyphenylalanine (DOPA; Y136DOPA) through mass spectrometric analysis. Y136DOPA modification was clearly detected by a specific antibody in the dopaminergic neurons of α-synuclein-overexpressing mice as well as human α-synucleinopathies. Furthermore, dopanized α-synuclein tended to form oligomers rather than large fibril aggregates and significantly enhanced neurotoxicity. Our findings suggest that the dopanization of α-synuclein by TH may contribute to oligomer and/or seed formation causing neurodegeneration with the potential to shed light on the pathogenesis of Parkinson's disease.

Functional Cooperation of α-Synuclein and Tau Is Essential for Proper Corticogenesis.

Alpha-synuclein (αSyn) and tau are abundant multifunctional neuronal proteins, and their intracellular deposits have been linked to many neurodegenerative diseases, including Alzheimer's disease and Parkinson's disease. Despite the disease relevance, their physiological roles remain elusive, as mice with knock-out of either of these genes do not exhibit overt phenotypes. To reveal functional cooperation, we generated αSyn-/-tau-/- double-knock-out mice and characterized the functional cross talk between these proteins during brain development. Intriguingly, deletion of αSyn and tau reduced Notch signaling and accelerated interkinetic nuclear migration of G2 phase at early embryonic stage. This significantly altered the balance between the proliferative and neurogenic divisions of progenitor cells, resulting in an overproduction of early born neurons and enhanced neurogenesis, by which the brain size was enlarged during the embryonic stage in both sexes. On the other hand, a reduction in the number of neural progenitor cells in the middle stage of corticogenesis diminished subsequent gliogenesis in the αSyn-/-tau-/- cortex. Additionally, the expansion and maturation of macroglial cells (astrocytes and oligodendrocytes) were suppressed in the αSyn-/-tau-/- postnatal brain, which in turn reduced the male αSyn-/-tau-/- brain size and cortical thickness to less than the control values. Our study identifies important functional cooperation of αSyn and tau during corticogenesis.SIGNIFICANCE STATEMENT Correct understanding of the physiological functions of αSyn and tau in CNS is critical to elucidate pathogenesis involved in the etiology of neurodegenerative diseases including Alzheimer's disease and Parkinson's disease. We show here that αSyn and tau are cooperatively involved in brain development via maintenance of progenitor cells. αSyn and tau double-knock-out mice exhibited an overproduction of early born neurons and accelerated neurogenesis at early corticogenesis. Furthermore, loss of αSyn and tau also perturbed gliogenesis at later embryonic stage, as well as the subsequent glial expansion and maturation at postnatal brain. Our findings provide new mechanistic insights and extend therapeutic opportunities for neurodegenerative diseases caused by aberrant αSyn and tau.

Lis1 mutation prevents basal radial glia-like cell production in the mouse.

Human cerebral cortical malformations are associated with progenitor proliferation and neuronal migration abnormalities. Progenitor cells include apical radial glia, intermediate progenitors and basal (or outer) radial glia (bRGs or oRGs). bRGs are few in number in lissencephalic species (e.g. the mouse) but abundant in gyrencephalic brains. The LIS1 gene coding for a dynein regulator, is mutated in human lissencephaly, associated also in some cases with microcephaly. LIS1 was shown to be important during cell division and neuronal migration. Here, we generated bRG-like cells in the mouse embryonic brain, investigating the role of Lis1 in their formation. This was achieved by in utero electroporation of a hominoid-specific gene TBC1D3 (coding for a RAB-GAP protein) at mouse embryonic day (E) 14.5. We first confirmed that TBC1D3 expression in wild-type (WT) brain generates numerous Pax6+ bRG-like cells that are basally localized. Second, using the same approach, we assessed the formation of these cells in heterozygote Lis1 mutant brains. Our novel results show that Lis1 depletion in the forebrain from E9.5 prevented subsequent TBC1D3-induced bRG-like cell amplification. Indeed, we observe perturbation of the ventricular zone (VZ) in the mutant. Lis1 depletion altered adhesion proteins and mitotic spindle orientations at the ventricular surface and increased the proportion of abventricular mitoses. Progenitor outcome could not be further altered by TBC1D3. We conclude that disruption of Lis1/LIS1 dosage is likely to be detrimental for appropriate progenitor number and position, contributing to lissencephaly pathogenesis.

U-Shaped Associations Between Urinary Iodine Concentration and the Prevalence of Metabolic Disorders: A Cross-Sectional Study.

Background: Iodine is important in both thyroid function and human metabolism. Studies have explored the effect of iodine on metabolic disorders through thyroid function. This study aimed to investigate the relationship between iodine status and metabolic disorders, such as metabolic syndrome (MetS), hypertension, impaired glucose metabolism, central obesity, and dyslipidemia. Methods: A total of 51,795 subjects aged ≥18 years from the TIDE (Thyroid Disorders, Iodine Status and Diabetes, a national epidemiological cross-sectional study) program were included. The prevalence of metabolic disorders and its related diseases was calculated based on the level of urinary iodine concentrations (UICs) using the chi-square method. To further explore whether the prevalence was associated with UIC, quadratic and UIC-stratified logistic regression models were used. Results: The prevalence of metabolic disorders as a function of UIC was found to be U-shaped with a lower prevalence of 76.0% at an UIC of 300-499 µg/L. Participants with an UIC of 300-499 µg/L showed an association with metabolic disorders (odds ratio [OR] = 0.857, 95% confidence interval [CI 0.796-0.922]) and hypertension (OR = 0.873 [CI 0.814-0.936]). An UIC of 300-799 µg/L was found to be associated with the occurrence of MetS and impaired glucose tolerance. An UIC of 500-799 µg/L was associated with the occurrence of prediabetes (OR = 0.883 [CI 0.797-0.978]). An UIC of ≥300 µg/L was associated with the occurrence of hypertriglyceridemia, hypercholesterolemia, and high levels of low-density lipoprotein cholesterol. Furthermore, an UIC of <100 µg/L showed an association with hypertension (OR = 1.097 [CI 1.035-1.162]) and hypercholesterolemia (OR = 1.178 [CI 1.117-1.242]). Conclusions: The association between UICs in adults and metabolic disorders and its related diseases is U-shaped. The association between UIC and metabolic disorders disappears in cases of iodine deficiency (<100 µg/L) or excess (≥500 µg/L).

Enhanced homologous recombination by the modulation of targeting vector ends.

The field of genome editing was founded on the establishment of methods, such as the clustered regularly interspaced short palindromic repeat (CRISPR) and CRISPR-associated protein (CRISPR/Cas) system, used to target DNA double-strand breaks (DSBs). However, the efficiency of genome editing also largely depends on the endogenous cellular repair machinery. Here, we report that the specific modulation of targeting vectors to provide 3' overhangs at both ends increased the efficiency of homology-directed repair (HDR) in embryonic stem cells. We applied the modulated targeting vectors to produce homologous recombinant mice directly by pronuclear injection, but the frequency of HDR was low. Furthermore, we combined our method with the CRISPR/Cas9 system, resulting in a significant increase in HDR frequency. Thus, our HDR-based method, enhanced homologous recombination for genome targeting (eHOT), is a new and powerful method for genome engineering.

Bone morphogenetic protein (BMP) 7 expression is regulated by the E3 ligase UBE4A in diabetic nephropathy.

Mesangial cells played a central role in the pathophysiology of diabetic nephropathy (DN). Our goal was to evaluate the molecular mechanism that regulates loss of BMP7 protein expression in DN. The mRNA and protein levels of BMP7 or UBE4A were detected using qRT-PCR and Western blot respectively. Mass spectrometry and co-immunoprecipitation were used to explore the E3 ligase which regulated BMP7 post-translationally. We initially confirmed that BMP7 protein, but not mRNA, is downregulated when cultured under high glucose mimicking DN conditions, which was rescued by MG-132 treatment. Proteomic analysis of NRK-52E cells ± MG-132 revealed a list of ubiquitin ligases associated with BMP7. Knockdown of the ubiquitin ligase UBE4A stabilized BMP7 expression in NRK-52E cells grown under high glucose conditions. Concurrent overexpression experiments confirmed that UBE4A is the ubiquitin ligase that degrades BMP7. Co-immunoprecipitation analysis confirmed that BMP7 and UBE4A interact. BMP7 expression in DN is regulated by post-translational mechanism.

Ultrasound-guided percutaneous microwave ablation of parotid gland adenolymphoma: A case report.

RATIONALE: Parotid gland adenolymphoma is one of the most common benign tumors in parotid gland, and mainly treated by surgery. Despite the widespread of ultrasound-guided percutaneous microwave ablation, there is no report concerning its application in parotid gland adenolymphoma. Herein, we reported a 2-year follow-up result of a male patient underwent ultrasound-guided percutaneous microwave ablation for parotid gland adenolymphoma. PATIENT CONCERNS: A 73-year-old man was admitted due to a hypoechoic nodule measuring 2.67 × 1.42 × 1.35 cm in posterior-inferior area of parotid gland with a high flow velocity in color Doppler flow imaging. DIAGNOSE: The lesion was pathologically diagnosed as parotid gland adenolymphoma. INTERVENTIONS: Ultrasound-guided percutaneous microwave ablation was performed to the tumor due to the fact that the patient refused to receive an open surgery in consideration of older age. OUTCOMES: The ablation procedure lasted about 2 minutes and 15 seconds, without significant adverse effect. The reduction ratios of tumor at postoperative 1 and 3-month were 53% and 82%, respectively. The tumor was fully absent at postoperative 8-month evaluation. Finally, there was no evident recurrence at postoperative 24-month evaluation. LESSONS: Ultrasound-guided percutaneous microwave ablation is a safe and effective treatment for parotid gland adenolymphoma, which may serve as a novel alternative approach for patients unsuitable for open surgery.

Proteasome subunit-α type-6 protein is post-transcriptionally repressed by the microRNA-4490 in diabetic nephropathy.

A common complication of both type I and type II diabetes is nephropathy, characterized by accumulation of extracellular matrix in the glomerular mesangium. This indicates a central role of mesangial cells in the pathophysiology of diabetic nephropathy. Using the proteomic approach, it was earlier elucidated in a rat model that the proteasome subunit-α type-6 protein (PSMA6) is suppressed in the renal cortex in nephropathic kidney. However, the underlying mechanism effecting suppression of PSMA6 protein in the renal cortex is not yet known. Twenty diabetic patients were enrolled and the expression level of PSMA6 in them was detected by immunohistochemistry. The protein and mRNA expression levels of PSMA6 in NRK-52E cells under high glucose condition were determined by Western blot and quantitative real-time PCR, respectively. Dual luciferase assay was used to detect the relationship of PSMA6 and miR-4490. Our results show that PSMA6 protein is down-regulated in patients with diabetic nephropathy compared with healthy control. Using the NRK-52E cell line cultured under high glucose condition as an in vitro model of diabetic nephropathy, we show that loss of PSMA6 protein expression occured independent of changes the in PSMA6 mRNA expression. We next elucidate that PSMA6 mRNA is post-transcriptionally regulated by the microRNA (miRNA)-4490, whose expression is inversely correlated to PSMA6 protein expression. Using reporter assays we show that PSMA6 is a direct target of the miR-4490. Exogenous manipulation of miR-4490 levels modulated expression of PSMA6, indicating that miR-4490 can be tested as a biomarker for nephropathy in diabetic patients.

A potentially new phase of the cardiac cycle: Pre-isovolumic contraction recognized by echocardiography.

Clinically the isovolumic contraction time (IVCT) can be measured by 3 echocardiographic methods of M-mode, pulse-wave Doppler (PWD), and tissue Doppler imaging (TDI). But IVCT can be clinically different by the 3 methods. This study is to investigate whether there is a potentially unidentified phase causing the discrepancies by analyzing electric mechanical delay time (EMD), IVCT, and pre-ejection period (PEP).A total of 30 healthy subjects were recruited for the study. EMD, IVCT, and PEP were obtained by the 3 methods, respectively. MCT (the interval from the onset of the QRS wave to the closure point of the mitral valve measured by TDI) and ICMC (the interval from the onset of IVC wave S1 to the closure point of the mitral valve measured by TDI) were both measured by color TDI.IVCTt (IVCT measured by TDI) was significantly longer than IVCTm or IVCTd (IVCT measured by M-mode or PWD) (both P < .0001), while EMDt (EMD measured by TDI) was significantly shorter than EMDm or EMDd (EMD measured by M-mode or PWD) (both P < .0001). But MCT was not significantly different from EMDm or EMDd (P > .05) and ICMC did not differ significantly from EMDm or EMDd minus EMDt or IVCTt minus IVCTm or IVCTd (P > .05), in other words, ICMC almost equaled to (EMDm or EMDd minus EMDt) or (IVCTt minus IVCTm or IVCTd).There may be an unidentified phase between the end of atrial contraction and the closure of mitral valve causing the discrepancies in IVCT, which is named as the pre-isovolumic contraction phase. It is a non-isovolumic phase and is included in the traditional isovolumic contraction phase.