Publications by authors named "Tianqi Wang"

179 Publications

Attention-Aware Discrimination for MR-to-CT Image Translation Using Cycle-Consistent Generative Adversarial Networks.

Radiol Artif Intell 2020 Mar 25;2(2):e190027. Epub 2020 Mar 25.

Department of Radiation Oncology, University of California, 1600 Divisidero St, San Francisco, CA 94115.

Purpose: To suggest an attention-aware, cycle-consistent generative adversarial network (A-CycleGAN) enhanced with variational autoencoding (VAE) as a superior alternative to current state-of-the-art MR-to-CT image translation methods.

Materials And Methods: An attention-gating mechanism is incorporated into a discriminator network to encourage a more parsimonious use of network parameters, whereas VAE enhancement enables deeper discrimination architectures without inhibiting model convergence. Findings from 60 patients with head, neck, and brain cancer were used to train and validate A-CycleGAN, and findings from 30 patients were used for the holdout test set and were used to report final evaluation metric results using mean absolute error (MAE) and peak signal-to-noise ratio (PSNR).

Results: A-CycleGAN achieved superior results compared with U-Net, a generative adversarial network (GAN), and a cycle-consistent GAN. The A-CycleGAN averages, 95% confidence intervals (CIs), and Wilcoxon signed-rank two-sided test statistics are shown for MAE (19.61 [95% CI: 18.83, 20.39], = .0104), structure similarity index metric (0.778 [95% CI: 0.758, 0.798], = .0495), and PSNR (62.35 [95% CI: 61.80, 62.90], = .0571).

Conclusion: A-CycleGANs were a superior alternative to state-of-the-art MR-to-CT image translation methods.© RSNA, 2020.
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http://dx.doi.org/10.1148/ryai.2020190027DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8017410PMC
March 2020

A Pilot Metabolomic Study on Myocardial Injury Caused by Chronic Alcohol Consumption-Alcoholic Cardiomyopathy.

Molecules 2021 Apr 9;26(8). Epub 2021 Apr 9.

Department of Forensic Pathology, School of Forensic Medicine, China Medical University, No. 77 Puhe Road, Shenyang North New Area, Shenyang 110122, China.

Chronic alcohol consumption leads to myocardial injury, ventricle dilation, and cardiac dysfunction, which is defined as alcoholic cardiomyopathy (ACM). To explore the induced myocardial injury and underlying mechanism of ACM, the Liber-DeCarli liquid diet was used to establish an animal model of ACM and histopathology, echocardiography, molecular biology, and metabolomics were employed. Hematoxylin-eosin and Masson's trichrome staining revealed disordered myocardial structure and local fibrosis in the ACM group. Echocardiography revealed thinning wall and dilation of the left ventricle and decreased cardiac function in the ACM group, with increased serum levels of brain natriuretic peptide (BNP) and expression of myocardial BNP mRNA measured through enzyme-linked immunosorbent assay and real-time quantitative polymerase chain reaction (PCR), respectively. Through metabolomic analysis of myocardium specimens, 297 differentially expressed metabolites were identified which were involved in KEGG pathways related to the biosynthesis of unsaturated fatty acids, vitamin digestion and absorption, oxidative phosphorylation, pentose phosphate, and purine and pyrimidine metabolism. The present study demonstrated chronic alcohol consumption caused disordered cardiomyocyte structure, thinning and dilation of the left ventricle, and decreased cardiac function. Metabolomic analysis of myocardium specimens and KEGG enrichment analysis further demonstrated that several differentially expressed metabolites and pathways were involved in the ACM group, which suggests potential causes of myocardial injury due to chronic alcohol exposure and provides insight for further research elucidating the underlying mechanisms of ACM.
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http://dx.doi.org/10.3390/molecules26082177DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8070378PMC
April 2021

Advances in Lipid-Based Nanoparticles for Cancer Chemoimmunotherapy.

Pharmaceutics 2021 Apr 9;13(4). Epub 2021 Apr 9.

Department of Biomedical and Pharmaceutical Sciences, University of Rhode Island, Kingston, RI 02881, USA.

Nanomedicines have shown great potential in cancer therapy; in particular, the combination of chemotherapy and immunotherapy (namely chemoimmunotherapy) that is revolutionizing cancer treatment. Currently, most nanomedicines for chemoimmunotherapy are still in preclinical and clinical trials. Lipid-based nanoparticles, the most widely used nanomedicine platform in cancer therapy, is a promising delivery platform for chemoimmunotherapy. In this review, we introduce the commonly used immunotherapy agents and discuss the opportunities for chemoimmunotherapy mediated by lipid-based nanoparticles. We summarize the clinical trials involving lipid-based nanoparticles for chemoimmunotherapy. We also highlight different chemoimmunotherapy strategies based on lipid-based nanoparticles such as liposomes, nanodiscs, and lipid-based hybrid nanoparticles in preclinical research. Finally, we discuss the challenges that have hindered the clinical translation of lipid-based nanoparticles for chemoimmunotherapy, and their future perspectives.
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http://dx.doi.org/10.3390/pharmaceutics13040520DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8069739PMC
April 2021

[Comparative study on the mechanical properties of lower limb arterial stents under various deformation modes].

Sheng Wu Yi Xue Gong Cheng Xue Za Zhi 2021 Apr;38(2):303-309

College of Mechanical Engineering, Inner Mongolia University of Technology, Hohhot 010051, P.R.China.

Lower extremity movement is a complex and large range of limb movement. Arterial stents implanted in lower extremity are prone to complex mechanical deformation, so the stent is required to have high comprehensive mechanical properties. In order to evaluate the mechanical property of different stents, in this paper, finite element method was used to simulate and compare the mechanical properties of six nitinol stents (Absolute Pro, Complete SE, Lifestent, Protégé EverFlex, Pulsar-35 and New) under different deformation modes, such as radial compression, axial compression/tension, bending and torsion, and the radial support performance of the stents was verified by experiments. The results showed that the comprehensive performance of New stent was better than other stents. Among which the radial support performance was higher than Absolute Pro and Pulsar-35 stent, the axial support performance was better than Complete SE, Lifestent and Protégé EverFlex stent, the flexibility was superior to Protégé Everflex stent, and the torsion performance was better than Complete SE, Lifestent and Protégé Everflex stent. The TTR2 type radial support force tester was used to test the radial support performance of 6 types, and the finite element analysis results were verified. The mechanical properties of the stent are closely related to the structural size. The result provides a reference for choosing a suitable stent according to the needs of the diseased location in clinical applications.
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http://dx.doi.org/10.7507/1001-5515.202006028DOI Listing
April 2021

Influences of Anatomorphological Features of the Portal Venous System on Postsplenectomy Hemodynamic Characteristics in Patients With Portal Hypertension: A Computational Model-Based Study.

Front Physiol 2021 12;12:661030. Epub 2021 Apr 12.

State Key Laboratory of Ocean Engineering, School of Naval Architecture, Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai, China.

Splenectomy, as an effective surgery for relieving complications caused by portal hypertension, is often accompanied by a significantly increased incidence of postoperative thrombosis in the portal venous system (PVS). While the underlying mechanisms remain insufficiently understood, the marked changes in hemodynamic conditions in the PVS following splenectomy have been suggested to be a potential contributing factor. The aim of this study was to investigate the influences of the anatomorphological features of the PVS on hemodynamic characteristics before and after splenectomy, with emphasis on identifying the specific anatomorphological features that make postoperative hemodynamic conditions more clot-promoting. For this purpose, idealized computational hemodynamics models of the PVS were constructed based on general anatomical structures and population-averaged geometrical parameters of the PVS. In the models, we incorporated various anatomorphological variations to represent inter-patient variability. The analyses of hemodynamic data were focused on the spatial distribution of wall shear stress (WSS) and the area ratio of wall regions exposed to low WSS (ALS). Obtained results showed that preoperative hemodynamic conditions were comparable among different models in terms of space-averaged WSS and ALS (all were small) irrespective of the considerable differences in spatial distribution of WSS, whereas, the inter-model differences in ALS were significantly augmented after splenectomy, with the value of ALS reaching up to over 30% in some models, while being smaller than 15% in some other models. Postoperative ALS was mainly determined by the anatomical structure of the PVS, followed by some morphogeometrical parameters, such as the diameter and curvature of the splenic vein, and the distance between the inferior mesenteric vein and splenoportal junction. Relatively, the angles between tributary veins and trunk veins only had mild influences on ALS. In addition, a marked increase in blood viscosity was predicted after splenectomy, especially in regions with low WSS, which may play an additive role to low WSS in initiating thrombosis. These findings suggest that the anatomical structure and some morphogeometrical features of the PVS are important determinants of hemodynamic conditions following splenectomy, which may provide useful clues to assessing the risk of postsplenectomy thrombosis based on medical imaging data.
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http://dx.doi.org/10.3389/fphys.2021.661030DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8072460PMC
April 2021

Interference of hemolysis on the postmortem biochemical analysis of IgE by ECLIA.

Int J Legal Med 2021 Mar 30. Epub 2021 Mar 30.

Department of Forensic Pathology, School of Forensic Medicine, China Medical University, No. 77, Puhe Road, Shenyang North New Area, Shenyang, 110122, Liaoning Province, People's Republic of China.

Forensic diagnosis of anaphylactic shock is a challenging task in forensic practice due to the lack of characteristic morphological changes. Postmortem analysis of serum IgE can provide helpful information for determining anaphylaxis. However, postmortem serum always suffers from hemolysis. To investigate the interference of hemolysis on postmortem analysis of total IgE by electrochemiluminescent immunoassay (ECLIA) and verify the suitability of the commercially available ECLIA kit for postmortem hemolyzed blood with the dilution-correction method, different levels of hemolyzed serum were prepared to evaluate the interference of hemolysis. A linear regression analysis was then performed on the concentration of total IgE in the completely hemolyzed blood and the corresponding serum. Our results indicated that hemolysis negatively interfered with the total IgE analysis by ECLIA and the interference (|Bias%|) increased with increasing levels of hemolysis. After controlling for |Bias%| by dilution, the test concentration of total IgE in the completely hemolyzed blood was still significantly lower than that in the serum (P < 0.05) and resulted in eight false-negative cases. A strong correlation was observed between the test concentration of total IgE in the completely hemolyzed blood and that in the serum (r = 0.983). After correction by the regression formula, the corrected concentration revealed no significant differences and exhibited the same diagnostic ability, compared with the serum total IgE concentration. These results indicate that the completely hemolyzed blood is not recommended for postmortem analysis of total IgE directly. The dilution-correction method might have potential utility in forensic practice for evaluating serum total IgE concentrations.
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http://dx.doi.org/10.1007/s00414-021-02578-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8008023PMC
March 2021

Crystal structures of two inhibitors in complex with histone lysine demethylase 4D (KDM4D) provide new insights for rational drug design.

Biochem Biophys Res Commun 2021 May 27;554:71-75. Epub 2021 Mar 27.

Department of Medicinal Chemistry, School of Medicine, Nankai University, Tianjin, 300071, PR China. Electronic address:

Histone lysine demethylase 4D (KDM4D), also known as JMJD2D, plays an important role in cell proliferation and survival and has been associated with several tumor types. KDM4D has emerged as a potential target for the treatment of human cancer. Here, we reported crystal complex structures for two KDM4D inhibitors, OWS [2-(1H-pyrazol-3-yl)isonicotinic acid] and 10r (5-hydroxy-2-methylpyrazolo[1,5-a]pyrido[3,2-e]pyrimidine-3-carbonitrile), which were both determined to 2.0 Å. OWS is a newly discovered KDM4D inhibitor (IC = 4.28 μM) and the critical pharmacophores of this compound are confirmed by the complex structure. Compound 10r is a KDM4D inhibitor reported by us previously. To clarify the binding mode in more detail, the crystal structure was determined and the comparison analysis revealed unique interactions that had never been observed before. Overall, our data provide new structural insights for rational design and offer an opportunity for optimization of KDM4D inhibitors.
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http://dx.doi.org/10.1016/j.bbrc.2021.03.083DOI Listing
May 2021

Adsorption and visible-light photocatalytic degradation of organic pollutants by functionalized biochar: Role of iodine doping and reactive species.

Environ Res 2021 Mar 17;197:111026. Epub 2021 Mar 17.

School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China; City University of Hong Kong Shenzhen Research Institute, 8 Yuexing 1st Road, Shenzhen Hi-Tech Industrial Park, Nanshan District, Shenzhen, 518060, China. Electronic address:

Here we developed the functionalized biochar as low-cost and heavy metal-free photocatalysts via a facile iodine doping method, which exhibit efficient adsorption and visible-light-driven photocatalytic degradation of representative organic pollutants, phenol and tetracycline. On one hand, iodine doping elevates the adsorption via creating extra pores, e.g., the adsorbed amounts of phenol by iodine-doped WSP and OSR biochar are increased by 161.8% and 146.3%, respectively, which in turn facilitates the photocatalytic oxidation of the adsorbed pollutants. On the other hand, iodine doping leads to the strong photo-induced excitation and remarkably reduced charge carrier transfer resistance, boosting the photocatalytic activity of iodine-doped biochar by more than 20 orders towards organic pollutants (e.g., phenol) degradation. The systematic analysis of reactive species reveals the active roles of O, HO, O, OH, electrons, and holes in photocatalytic process and identifies O to be the major contributor. This work affords a facile approach to generating porous and visible-light-driven photocatalyst from biomass for efficient adsorbing and degrading organic pollutants, opening up an avenue to turn biowaste into biomaterials for sustainable environmental remediation.
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http://dx.doi.org/10.1016/j.envres.2021.111026DOI Listing
March 2021

A robust and flexible CRISPR/Cas9-based system for neutrophil-specific gene inactivation in zebrafish.

J Cell Sci 2021 Apr 22;134(8). Epub 2021 Apr 22.

Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA.

CRISPR/Cas9-based tissue-specific knockout techniques are essential for probing the functions of genes in embryonic development and disease using zebrafish. However, the lack of capacity to perform gene-specific rescue or live imaging in the tissue-specific knockout background has limited the utility of this approach. Here, we report a robust and flexible gateway system for tissue-specific gene inactivation in neutrophils. Using a transgenic fish line with neutrophil-restricted expression of Cas9 and ubiquitous expression of single guide (sg)RNAs targeting rac2, specific disruption of the rac2 gene in neutrophils is achieved. Transient expression of sgRNAs targeting rac2 or cdk2 in the neutrophil-restricted Cas9 line also results in significantly decreased cell motility. Re-expressing sgRNA-resistant rac2 or cdk2 genes restores neutrophil motility in the corresponding knockout background. Moreover, active Rac and force-bearing F-actins localize to both the cell front and the contracting tail during neutrophil interstitial migration in an oscillating fashion that is disrupted when rac2 is knocked out. Together, our work provides a potent tool that can be used to advance the utility of zebrafish in identifying and characterizing gene functions in a tissue-specific manner.
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http://dx.doi.org/10.1242/jcs.258574DOI Listing
April 2021

Design, synthesis and biological assessment of novel CDK4 inhibitor with potent anticancer activity.

Bioorg Chem 2021 Apr 8;109:104717. Epub 2021 Feb 8.

Department of Medicinal Chemistry, School of Medicine, Nankai University, 94 Weijin Road, Tianjin, China. Electronic address:

Efforts toward finding potent CDK4 inhibitor for cancer therapy, a series of fluorine substituted pyrrolo[2,3-d]pyrimidine derivatives were designed, synthesized, and evaluated. Among them, the optimal lead compound 18i was discovered with potent activity against CDK4 at the nanomolar level (IC = 2.5 nM) and exquisite selectivity which demonstrated only modest activity against 3 out of the 394 protein kinases. 18i exhibited a much greater in vitro antiproliferative activity against several human cancer cell lines than that of the approved drug ribociclib. Further mechanism studies revealed that 18i effectively stimulated cancer cell cycle arrest in G phase and induced tumor cell apoptosis. In the comparison of in vivo therapeutic effects in xenograft mouse models of breast cancer, oral administration of 18i showed a significantly better degree of inhibitory effect to ribociclib without obvious toxicity. All of the results indicated that 18i could be a promising CDK4 inhibitor for treating malignancies.
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http://dx.doi.org/10.1016/j.bioorg.2021.104717DOI Listing
April 2021

A network pharmacology approach: Inhibition of the NF-κB signaling pathway contributes to the NASH preventative effect of an Oroxylum indicum seed extract in oleic acid-stimulated HepG2 cells and high-fat diet-fed rats.

Phytomedicine 2021 Feb 12:153498. Epub 2021 Feb 12.

College of Life Science, Yangtze University, Jingzhou, Hubei 434000, China. Electronic address:

Background: The incidence of nonalcoholic fatty liver disease (NAFLD), especially nonalcoholic steatohepatitis (NASH), has significantly increased in recent years and has become an important public health issue. However, no U.S. Food and Drug Administration (FDA)-approved first-line drug is currently available for the treatment of NAFLD and NASH; therefore, research on new drugs is currently a hot topic. Oroxylum indicum (Linn.) Kurz is extensively distributed in South China and South Asia and has many biological activities. However, its effects on NAFLD or even NASH and the corresponding mechanisms are still not clear.

Purpose: To investigate the effect and mechanism of O. indicum seed extract (OISE) on preventing anti-inflammatory action in the progression from simple nonalcoholic fatty liver (NAFL) to NASH.

Methods: A network pharmacology method to construct ingredient-target networks and the protein-protein interaction (PPI) network of OISE in NASH were constructed for topological analyses and hub-target screening. Enrichment analyses were performed to identify the critical biological processes and signaling pathways. Simultaneously, in vitro and in vivo experiments investigated the effect and mechanism of OISE, baicalein, and chrysin on inflammation by biochemical indicator detection, luciferase reporters, pathological staining, and immunoblotting in oleic acid-stimulated HepG2 cells or in high-fat diet-fed rats.

Results: The network pharmacology showed that OISE prevented the development and progression of NAFL into NASH through various pathways and targets and that the nuclear factor NF-κB (NF-κB) pathway regulated by baicalein and chrysin played an important role in the treatment of NASH. In in vitro experiments, we further showed that OISE and its ingredients, namely, baicalein and chrysin, all improved the inflammatory status in oleic acid-stimulated HepG2 cells, inhibited the nuclear transcriptional activities of NF-κB, increased the IκB level, and decreased the phosphorylation level of NF-κB. Furthermore, in a high-fat diet-induced NASH model in rats, we also showed that OISE prevented the development and progression of NASH by inhibiting the nuclear transcriptional activity of NF-κB.

Conclusion: OISE suppressed inflammatory responses and prevented the development and progression of NAFL into NASH through inhibition of the nuclear transcriptional activity of NF-κB. OISE may be used to treat NAFLD through many functions, including an increase in insulin sensitivity, a decrease in lipid accumulation in the liver, suppression of inflammation, and clearance of free radicals.
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http://dx.doi.org/10.1016/j.phymed.2021.153498DOI Listing
February 2021

Leader-Following Event-Triggered Adaptive Practical Consensus of Multiple Rigid Spacecraft Systems Over Jointly Connected Networks.

IEEE Trans Neural Netw Learn Syst 2021 Feb 15;PP. Epub 2021 Feb 15.

In this article, we study the leader-following practical attitude consensus problem of a group of multiple uncertain rigid spacecraft systems over jointly connected networks by a distributed event-triggered control law. We first establish a lemma that allows the problem to be converted to a distributed practical stabilization problem of a well-defined uncertain dynamical system. Then, we combine the adaptive distributed observer technique and the adaptive control technique to design an event-triggered adaptive control law and an event-triggered mechanism to solve our problem. The effectiveness of our design is illustrated by a numerical example.
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http://dx.doi.org/10.1109/TNNLS.2021.3056141DOI Listing
February 2021

Fe nanopowder-assisted fabrication of FeO/porous carbon for boosting potassium-ion storage performance.

Nanoscale 2021 Jan 20;13(4):2481-2491. Epub 2021 Jan 20.

School of Materials Science and Engineering, Ocean University of China. 238 Songling Road, Laoshan District, Qingdao, China.

The electrode materials of potassium ion storage system have attracted considerable attention given the promising prospect of a potassium ion system in large-scale electrochemical energy storage applications. Despite the excellent anode performance of metal oxides in Li and Na batteries, the study on their K storage performance is still rarely reported. In this study, we report a safe and low-cost strategy to prepare FeO/N-doped carbons by using NaHCO and Fe nanopowder. Benefiting from the oxidation of Fe to FeO, an interesting "one stone, two birds" role of the Fe powder can be identified in the heating process. As a reduction agent, the Fe powder can consume the excess oxygen in the bio-massed carbon framework, facilitating the formation of short-range-ordered domains in the biomass-derived carbon materials (FeO@GBHCs). Moreover, the close combination of oxidization products (FeO particles) and carbon matrix leads to numerous FeO clusters grafted on the surface of the carbon framework via the strong C-O-Fe binding. Therefore, the resultant FeO/porous carbon exhibits a high reversible capacity of 410 mA h g and an excellent cycling capability. The assembled FeO@GBHCs//AC potassium-ion hybrid supercapacitor delivers a high energy density of 133 W h kg at a power density of 700 W kg, demonstrating a potential prospect of metal oxides in boosting the potassium ion storage performance.
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http://dx.doi.org/10.1039/d0nr08711dDOI Listing
January 2021

The pathway of recombining short homologous ends in Escherichia coli revealed by the genetic study.

Mol Microbiol 2020 Dec 29. Epub 2020 Dec 29.

State Key Laboratory of Microbial Technology, Shandong University, Qingdao, People's Republic of China.

The recombination of short homologous ends in Escherichia coli has been known for 30 years, and it is often used for both site-directed mutagenesis and in vivo cloning. For cloning, a plasmid and target DNA fragments were converted into linear DNA fragments with short homologous ends, which are joined via recombination inside E. coli after transformation. Here this mechanism of joining homologous ends in E. coli was determined by a linearized plasmid with short homologous ends. Two 3'-5' exonucleases ExoIII and ExoX with nonprocessive activity digested linear dsDNA to generate 5' single-strand overhangs, which annealed with each other. The polymerase activity of DNA polymerase I (Pol I) was exclusively employed to fill in the gaps. The strand displacement activity and the 5'-3' exonuclease activity of Pol I were also required, likely to generate 5' phosphate termini for subsequent ligation. Ligase A (LigA) joined the nicks to finish the process. The model involving 5' single-stranded overhangs is different from established recombination pathways that all generate 3' single-stranded overhangs. This recombination is likely common in bacteria since the involved enzymes are ubiquitous.
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http://dx.doi.org/10.1111/mmi.14677DOI Listing
December 2020

[Application of biomechanical modeling and simulation in the development of non-invasive technologies and devices for cardiovascular testing].

Sheng Wu Yi Xue Gong Cheng Xue Za Zhi 2020 Dec;37(6):990-999

School of Naval Architecture, Ocean & Civil Engineering, Shanghai Jiao Tong University, Shanghai 200240, P.R.China.

The prevalence of cardiovascular disease in our country is increasing, and it has been a big problem affecting the social and economic development. It has been demonstrated that early intervention of cardiovascular risk factors can effectively reduce cardiovascular disease-caused mortality. Therefore, extensive implementation of cardiovascular testing and risk factor screening in the general population is the key to the prevention and treatment of cardiovascular disease. However, the categories of devices available for quick cardiovascular testing are limited, and in particular, many existing devices suffer from various technical problems, such as complex operation, unclear working principle, or large inter-individual variability in measurement accuracy, which lead to an overall low popularity and reliability of cardiovascular testing. In this study, we introduce the non-invasive measurement mechanisms and relevant technical progresses for several typical cardiovascular indices (e.g., peripheral/central arterial blood pressure, and arterial stiffness), with emphasis on describing the applications of biomechanical modeling and simulation in mechanism verification, analysis of influential factors, and technical improvement/innovation.
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http://dx.doi.org/10.7507/1001-5515.202008076DOI Listing
December 2020

Efficacy and Safety of Combination Comprising Tamsulosin and PDE5-Is, Relative to Monotherapies, in Treating Lower Urinary Tract Symptoms and Erectile Dysfunction Associated With Benign Prostatic Hyperplasia: A Meta-Analysis.

Am J Mens Health 2020 Nov-Dec;14(6):1557988320980180

Department of Urology, Affiliated Yantai Yuhuangding Hospital, Qingdao University, Yantai, Shandong, China.

We report safety and efficacy of a combination therapy, comprising tamsulosin and phosphodiesterase type 5 inhibitors (PDE5-Is), relative to monotherapy, to ascertain its potential in treating lower urinary tract symptoms (LUTS) and erectile dysfunction (ED) secondary to benign prostatic hyperplasia (BPH) after 3 months' treatment. We screened MEDLINE, EMBASE, and the Cochrane Controlled Trials Register databases, for randomized controlled trials, and obtained eight articles comprising 1144 participants. Results showed that the combination group had superior outcomes with regard to International Prostate Symptom Score (IPSS) and Qmax, compared to the other two groups. The combination group also had superior efficacy with regard to International Index of Erectile Function (IIEF) than the tamsulosin group, but not over the PDE5-Is group. Further, the combination group showed better efficacy in IPSS voiding and quality of life (QoL) compared to the PDE5-Is group. An analysis of safety outcomes revealed extremely high adverse events (AEs) and pain in the combination group. However, therapy discontinuation due to pain and AEs did not increase with increase in AEs. Overall, our findings indicate that a combination of tamsulosin and PDE5-Is is superior to individual tamsulosin and PDE5-Is monotherapy, with regard to improving LUTS and ED secondary to BPH.
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http://dx.doi.org/10.1177/1557988320980180DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7756049PMC
December 2020

High genetic burden in 163 Chinese children with status epilepticus.

Seizure 2021 Jan 24;84:40-46. Epub 2020 Nov 24.

Department of Neurology, Children's Hospital of Fudan University, Shanghai, China. Electronic address:

Purpose: This study aimed to investigate the genetic aetiology in Chinese children diagnosed with status epilepticus (SE).

Methods: Next-generation sequencing, copy number variation (CNV) analysis, and other genetic testing methods were conducted for children with SE lacking an identifiable non-genetic aetiology. Furthermore, the phenotype and molecular data of patients with SE were retrospectively analysed.

Results: Among children with SE lacking an identifiable non-genetic aetiology, 73 out of 163 children (44.8 %) were found to have causative variants associated with SE including 66 monogenic mutations in 22 genes and 7 CNVs. Based on the American College of Medical Genetics and Genomics scoring system, the monogenic variants included 64 pathogenic/likely pathogenic and 2 uncertain significance variants. SCN1A gene mutations (n = 32) were the most common cause, followed by TSC2 (n = 5), CACNA1A (n = 5), SCN2A (n = 4), SCN9A (n = 2) and DEPDC5 (n = 2) gene mutations. Sixteen mutations were identified in single genes. Furthermore, 51 (77.3 %) monogenic mutations were de novo. Age at SE onset < 1 year (odds ratio [OR] = 2.70, 95 % confidence interval [CI]: 1.25-5.83, p = 0.012) and co-morbidity of intellectual disability (OR = 3.36, 95 %CI: 1.61-6.99, p = 0.001) were independently associated with pathogenic genetic variants.

Conclusion: This study identified genetic aetiology in 44.8 % of patients with SE, which indicates a high burden of genetic aetiology among children with SE in China. Our findings highlight the importance for genetic testing of children with SE that lacks an identifiable non-genetic aetiology.
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http://dx.doi.org/10.1016/j.seizure.2020.10.032DOI Listing
January 2021

Self-Assembled Periodic Nanostructures Using Martensitic Phase Transformations.

Nano Lett 2021 Feb 2;21(3):1246-1252. Epub 2020 Dec 2.

Department of Chemical Engineering and Materials Science, University of Minnesota, Twin Cities, Minneapolis, Minnesota 55455, United States.

We describe a novel approach for the rational design and synthesis of self-assembled periodic nanostructures using martensitic phase transformations. We demonstrate this approach in a thin film of perovskite SrSnO with reconfigurable periodic nanostructures consisting of regularly spaced regions of sharply contrasted dielectric properties. The films can be designed to have different periodicities and relative phase fractions via chemical doping or strain engineering. The dielectric contrast within a single film can be tuned using temperature and laser wavelength, effectively creating a variable photonic crystal. Our results show the realistic possibility of designing large-area self-assembled periodic structures using martensitic phase transformations with the potential of implementing "built-to-order" nanostructures for tailored optoelectronic functionalities.
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http://dx.doi.org/10.1021/acs.nanolett.0c03708DOI Listing
February 2021

The role of Hipk2-p53 pathways in arsenic-induced autistic behaviors: A translational study from rats to humans.

Environ Pollut 2020 Dec 31;267:115568. Epub 2020 Aug 31.

Department of Neurology, Children's Hospital of Fudan University, Shanghai, 201102, China. Electronic address:

Previous studies have associated the risk of autism spectrum disorder (ASD) with increased exposures to metals and metalloids such as arsenic. In this study, we used an animal-to-human translational strategy to identify key molecular changes that potentially mediated the effects of arsenic exposures on ASD development. In a previously established rat model, we have induced autistic behaviors in rat pups with gestational arsenic exposures (10 and 45 μg/L AsO in drinking water). Neuronal apoptosis and the associated epigenetic dysregulations in frontal cortex were assayed to screen potential mediating pathways, which were subsequently validated with qPCR, western blotting, and immunohistochemistry analyses. Furthermore, the identified pathway, along with serum levels of 26 elements including arsenic, were characterized in a case-control study with 21 ASD children and 21 age-matched healthy controls. In animals, we found that arsenic exposures caused difficulties of social interaction and increased stereotypic behaviors in a dose-dependent manner, accompanied by increased neuronal apoptosis and upregulation of Hipk2-p53 pathway in the frontal cortex. In humans, we found that serum levels of Hipk2 and p53 were 24.7 (95%CI: 8.5 to 43.4) % and 23.7 (95%CI: 10.5 to 38.5) % higher in ASD children than in healthy controls. ASD children had significantly higher serum levels of 15 elements, among which arsenic, silicon, strontium, and vanadium were positively associated with both Hipk2 and p53. Results from both the rat arsenic exposure and human case-control studies suggest a likely role of Hipk2-p53 pathway in ASD development induced by exposures to environmental pollutants such as arsenic.
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http://dx.doi.org/10.1016/j.envpol.2020.115568DOI Listing
December 2020

Dynamic interactions between soil cadmium and zinc affect cadmium phytoavailability to rice and wheat: Regional investigation and risk modeling.

Environ Pollut 2020 Dec 9;267:115613. Epub 2020 Sep 9.

State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, PR China.

Characterizing the interactions between Cd and Zn with respect to the soil soluble Cd and crop Cd uptake allows the development of risk-based approaches to the performance of grain crops. By means of a three-year survey of 358 rice fields and 206 wheat fields across China, this study investigated the effect of Cd-Zn interactions on the phytoavailability of Cd to rice and wheat. The interactive nature between the Cd:Zn ratio and pH of soil affected crop Cd uptake, and the resulting grain Cd intake risk, were examined by the Free-Ion Activity-based model and probability analysis. In highly acidic rice soils (pH < 5.9), soil Zn had no effect on rice Cd uptake, whereas, under near-neutral conditions (pH > 5.9), a site-specific influence of soil Zn on grain Cd concentration was found. Soil Zn could inhibit Cd uptake and translocation by the plant in soil-wheat system when the soil Cd:Zn ratio decreased to 0.0083 and lower. Rice grain poses a significant health risk to local consumers due to its high Cd accumulation and its low Zn accumulation. In order to reduce the health risks from dietary Cd to local consumers, approximately 63.9% of the rice fields and 30.5% of the wheat fields require strategies ameliorating soil acidity in rice soils and increasing Zn concentrations in wheat soils.
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http://dx.doi.org/10.1016/j.envpol.2020.115613DOI Listing
December 2020

Complete retroperitoneal laparoscopic nephroureterectomy with bladder cuff excision for upper tract urothelial carcinoma without patient repositioning: a single-center experience.

J Int Med Res 2020 Nov;48(11):300060520973915

Department of Urology, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, Yantai, Shandong, China.

Objective: This study was performed to evaluate the outcome of complete retroperitoneal laparoscopic nephroureterectomy with bladder cuff excision (RLNU-BCE), which is performed to treat urothelial carcinomas in the renal pelvis or in the ureter higher than the crossing of the common iliac artery without patient repositioning.

Methods: We retrospectively analyzed the clinical data of 48 patients with upper tract urothelial carcinoma who underwent complete RLNU-BCE in our institution from May 2017 to September 2019.

Results: RLNU-BCE was successfully performed in all 48 patients. The median operation time was 110 minutes [interquartile range (IQR), 100-130 minutes], and the median postoperative anesthesia recovery time was 10 minutes (IQR, 7-15 minutes). The median postoperative hospitalization period was 5 days (IQR, 4-6 days). Pathologic examination revealed that the margin of all resected specimens was negative. After a median follow-up of 13 months (IQR, 7-20 months), no local recurrence or distant metastasis was found. No complications occurred during follow-up.

Conclusion: Based on our experience with this technique, RLNU-BCE deserves application and promotion in clinical practice. Long-term comparative studies are required to confirm its superiority over other techniques.
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http://dx.doi.org/10.1177/0300060520973915DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7705383PMC
November 2020

Modified DMEM xenic culture medium for propagation, isolation and maintenance of Balantioides coli.

Acta Trop 2021 Feb 21;214:105762. Epub 2020 Nov 21.

Parasitology Laboratory, College of Animal Science and Technology, Henan University of Science and Technology, Luoyang 471023, China.

Balantioides coli is a known ciliated zoonotic protozoan that mainly causes diarrhea in humans and pigs. An efficient and reliable culture system for this parasite remains unavailable until now. In this study, a modified Dulbecco's modified eagle medium (DMEM) with pH 7.0-7.5, containing 5 mg/mL starch and 20% new calf serum, was optimized for propagation of B. coli at 28°C-32°C. At the growth-peaking stage, the average trophozoite density was up to 12,970 trophozoites per milliliter. A reproducible protocol for isolation and maintenance of this parasite was also developed based on the modified DMEM culture medium. Moreover, cloning results of B. colipopulations showed that 250 trophozoites in 3 mL modified DMEM medium were the minimal number of trophozoites that propagated to the growth-peaking stage, and finally obtained the individual population. However, less than 250 trophozoites failed to continuously grow in the modified DMEM culture medium under the optimal conditions for growth of B. coli. These data showed that the modified DMEM culture medium is an ideal and efficient medium for propagation and maintenance of B. coli in vitro and will help studies on its biology, genome, transcriptome, proteome, and drug screening.
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http://dx.doi.org/10.1016/j.actatropica.2020.105762DOI Listing
February 2021

The second to fourth digit ratio (2D:4D): A risk factor of bladder cancer in men.

Early Hum Dev 2021 Jan 10;152:105247. Epub 2020 Nov 10.

Department of Urology, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, Yantai, Shandong, China. Electronic address:

Background: Exposure to prenatal sex steroids as indicated by the ratio of the second to fourth digit length (2D:4D) has been linked to the risk of onset of cancer, while sex steroids may expand the gender disparity in bladder cancer (BC) morbidity.

Aim: To explore the association between 2D:4D ratio and BC risk.

Subjects: 307 bladder cancer patients and 321 cancer-free individuals.

Outcome Measures: Relationships between 2D:4D and incidence of bladder cancer.

Results: For males, a lower 2D:4D ratio of both hands was obtained in the BC group, relative to the control group (left hand: 0.940 ± 0.031 vs. 0.954 ± 0.024, t = -4.72, p < 0.001, Cohen's d = 0.491 and right hand: 0.939 ± 0.031 vs. 0.952 ± 0.022, t = -4.493, p < 0.001, Cohen's d = 0.511). In females, no differences in the 2D:4D ratio were observed between the BC and control groups (p > 0.05). Correlation analysis between 2D:4D ratio and pathological index found no correlation among the BC grade or stage (p > 0.05).

Conclusion: Men with BC have a lower 2D:4D ratio compared with healthy men. Therefore, having a low 2D:4D ratio is a risk factor for BC in men. Prenatal exposure to sex steroids might play a role in the etiology of BC, which could partially explain the gender disparity in the prevalence of BC.
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http://dx.doi.org/10.1016/j.earlhumdev.2020.105247DOI Listing
January 2021

Sudden Death Due to Severe Ovarian Hyperstimulation Syndrome: An Autopsy-Centric Case Report.

Am J Forensic Med Pathol 2021 Mar;42(1):88-91

From the Department of Forensic Pathology, China Medical University School of Forensic Medicine, Shenyang, Liaoning Province.

Abstract: Ovarian hyperstimulation syndrome (OHSS) is a rare iatrogenic disorder associated with controlled ovarian stimulation during assisted reproductive technology. Severe OHSS may impose serious complications, including pleural effusion, acute renal insufficiency, venous thrombosis, and even death, although lethal outcomes are rare in forensic practice. The reported incidence of severe OHSS ranges from 0.008% to 10%. Herein, we present the case of a 29-year-old woman who diagnosed with polycystic ovary syndrome and infertility chose to undergo assisted reproduction. She received leuprorelin acetate and follicle stimulating hormone prior to egg retrieval. Three days after the retrieval procedure, she developed abdominal pain and distension. Later that same day, she died unexpectedly. The subsequent autopsy revealed turbid effusions of pleural and peritoneal cavities, abnormal ovarian enlargement, and duskiness of multiple organ surfaces. Microscopic examination disclosed edema and hemorrhage in follicles of both ovaries, thrombosis within the myocardial matrix, and massive pulmonary edema. Routine toxicology screening was negative. The death was attributed to severe OHSS. This case provides a morphologic reference for clinical and forensic work. Autopsy findings in instances of severe OHSS provide valuable insight into the mechanisms and pathogenesis of this disease.
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http://dx.doi.org/10.1097/PAF.0000000000000601DOI Listing
March 2021

Alterations in the diversity and composition of gut microbiota in weaned piglets infected with Balantioides coli.

Vet Parasitol 2020 Dec 3;288:109298. Epub 2020 Nov 3.

Parasitology Laboratory, College of Animal Science and Technology, Henan University of Science and Technology, Luoyang 471023, China.

Balantioides coli is a ciliated parasite that can cause diarrhea when inhabiting the colon and cecum of pigs and humans. However, information regarding the changes in structure and composition of the gut microbiome in piglets infected with B. coli remains scarce. In this study, 16S rDNA amplicon sequencing was conducted on fecal samples from both B. coli-positive piglets with diarrhea and B. coli-negative piglets without diarrhea. The results showed that Firmicutes and Bacteroidetes were the major phyla in the two groups, and the relative abundance of the phylum Firmicutes, including Ruminococcaceae and Clostridiaceae, was significantly lower in the B. coli-positive samples than in the B. coli-negative ones (p < 0.05). Compared with B. coli-negative samples, Alloprevotella and Faecalibacterium showed distinctly higher relative abundances (p < 0.05) in the B. coli-positive samples, and the abundances of some potential pathogenic bacteria, including Escherichia-Shigella and Campylobacter, were positively correlated with B. coli infection and diarrhea of weaned piglets. In addition, there were statistically significant differences in fecal microbiota diversity and abundances of predicted functional genes between B. coli-colonized and B. coli-negative samples (p <  0.05). Taken together, these findings suggest that there were significant differences in the bacterial community composition, diversity, and functions between the B. coli-positive and B. coli-negative piglets, and the colonization by B. coli may be associated with the dysbiosis of gut microbiota structure in weaned piglets.
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http://dx.doi.org/10.1016/j.vetpar.2020.109298DOI Listing
December 2020

LBBAP in patients with normal intrinsic QRS duration: Electrical and mechanical characteristics.

Pacing Clin Electrophysiol 2021 01 12;44(1):82-92. Epub 2021 Jan 12.

Department of Cardiology, Nanjing Drum Tower Hospital, Clinical College of Nanjing Medical University, Nanjing, China.

Background: Left bundle branch area pacing (LBBAP) is an innovative pacing technology, which needs further study.

Methods: Seventy LBBAP patients with intrinsic QRS duration (QRSd) less than 120 ms were consecutively enrolled in our center. According to whether the left bundle branch potential (LBBp) was recorded or not, the patients were divided into the potential positive group (LBBAP+) and the potential negative group (LBBAP-). Electrocardiographic and echocardiographic parameters were used to evaluate electrical and mechanical characteristics. Lead parameters and complications were followed-up.

Results: There were 52 patients in LBBAP+ and 18 patients in LBBAP-. The QRSd and the left ventricular activation time (LVAT) were wider after LBBAP. QRSd showed no significant difference between LBBAP+ and LBBAP-. LVAT was significantly shorter in LBBAP+ than in LBBAP-. Frontal QRS axis shifted leftward and the V1 morphologies changed after LBBAP. QRS axis and V1 morphologies showed no significant differences between two groups. Paced R-wave transition moved forward compared with intrinsic R-wave transition in both groups. Peak systolic strain of left ventricle (LVPSS) increased, and peak systolic dispersion of left ventricle (LVPSD) did not change significantly after LBBAP. Systolic and diastolic function as well as mechanical synchronism had no significant differences between two groups. LBBAP had great pacing parameters.

Conclusion: LBBAP changes electrical and mechanical characteristics and has good safety in patients with normal intrinsic QRSd. LBBAP+ and LBBAP- show no significant differences in mechanical synchronization and interventricular electrical synchronization. The LBBAP+ shows better left ventricular electrical synchronicity.
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http://dx.doi.org/10.1111/pace.14114DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7898286PMC
January 2021

Systematic Review and Meta-Analysis of the Efficacy and Safety of Enhanced Recovery After Surgery vs. Conventional Recovery After Surgery on Perioperative Outcomes of Radical Cystectomy.

Front Oncol 2020 23;10:541390. Epub 2020 Sep 23.

Department of Urology, Yantai Yuhuangding Hospital, Qingdao University, Yantai, China.

Radical cystectomy has been characterized as the most difficult operation in urology because of the complex surgical procedures and postoperative complications. Enhanced recovery after surgery (ERAS), which reduces the incidence of perioperative complications, has been widely used in clinical surgery. Herein, we performed a meta-analysis to evaluate the efficacy and safety of ERAS vs. conventional recovery after surgery (CRAS) on perioperative outcomes of radical cystectomy. We performed a systematic search of randomized controlled trials (RCTs) in the following databases: Medline, Embase, and the Cochrane Controlled Trials Register, based on the PICOS strategy. The reference lists of the retrieved studies were further surveyed for relevant publications. Our search yielded seven RCTs containing 813 patients. The ERAS group was found to have better performance in the following parameters: length of hospital stay [mean difference (MD) = -1.12, 95% confidence interval (CI): -1.80 to -0.45, = 0.001], time to first flatus (MD = -0.70, 95% CI: -0.98 to 0.41, < 0.00001), and time to regular diet (MD = -0.12, 95% CI: -1.76 to -0.28, = 0.007). However, there were no significant differences between the two groups in major complications [odds ratio (OR) = 0.91, 95% CI: 0.63 to 1.34, = 0.64], readmission (OR = 1.15, 95% CI: 0.65 to 2.01, = 0.63), ileus (OR = 0.75, 95% CI: 0.44 to 1.28, = 0.29), wound infection (OR = 0.56, 95% CI: 0.31 to 1.01, = 0.05), mortality (OR = 0.69, 95% CI: 0.24 to 1.99, = 0.49), or time to first bowel movement (MD = -0.55, 95% CI: -1.62 to 0.53, = 0.32). ERAS reduced the length of hospital stay, time to first flatus, and time to regular diet after cystectomy. Compared to CRAS protocols, ERAS protocols do not increase the risk of adverse events.
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http://dx.doi.org/10.3389/fonc.2020.541390DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7538712PMC
September 2020

Tongmai Yangxin pill reduces myocardial No-reflow via endothelium-dependent NO-cGMP signaling by activation of the cAMP/PKA pathway.

J Ethnopharmacol 2021 Mar 12;267:113462. Epub 2020 Oct 12.

Institute of Traditional Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 300193, China. Electronic address:

Ethnopharmacological Relevance: The Tongmai Yangxin pill (TMYX) is derived from the Zhigancao decoction recorded in Shang han lun by Zhang Zhongjing during the Han dynasty. TMYX is used for the clinical treatment of chest pain, heartache, and qi-yin-deficiency coronary heart disease. Previous studies have confirmed that TMYX can improve vascular endothelial function in patients with coronary heart disease by upregulating nitric oxide activity and then regulating vascular tension. Whether TMYX can further improve myocardial NR by upregulating NO activity and then dilating blood vessels remains unclear.

Aim Of The Study: This study aimed to reveal whether TMYX can further improve myocardial NR by upregulating NO activity and then dilating blood vessels. The underlying cAMP/PKA and NO-cGMP signaling pathway-dependent mechanism is also explored.

Materials And Methods: The left anterior descending coronary arteries of healthy adult male SD rats were ligated to establish the NR model. TMYX (4.0 g/kg) was orally administered throughout the experiment. Cardiac function was measured through echocardiography. Thioflavin S, Evans Blue, and TTC staining were used to evaluate the NR and ischemic areas. Pathological changes in the myocardium were assessed by hematoxylin-eosin staining. An automated biochemical analyzer and kit were used to detect the activities of myocardial enzymes and myocardial oxidants, including CK, CK-MB, LDH, reactive oxygen species, superoxide dismutase, malonaldehyde, and NO. The expression levels of genes and proteins related to the cAMP/PKA and NO/cGMP signaling pathways were detected via real-time fluorescence quantitative PCR and Western blot analysis, respectively. A microvascular tension sensor was used to detect coronary artery diastolic function in vitro.

Results: TMYX elevated the EF, FS, LVOT peak, LVPWd and LVPWs values, decreased the LVIDd, LVIDs, LV-mass, IVSd, and LV Vols values, demonstrating cardio-protective effects, and reduced the NR and ischemic areas. Pathological staining showed that TMYX could significantly reduce inflammatory cell number and interstitial edema. The activities of CK, LDH, and MDA were reduced, NO activity was increased, and oxidative stress was suppressed after treatment with TMYX. TMYX not only enhanced the expression of Gs-α, AC, PKA, and eNOS but also increased the expression of sGC and PKG. Furthermore, TMYX treatment significantly decreased ROCK expression. We further showed that TMYX (25-200 mg/mL) relaxed isolated coronary microvessels.

Conclusions: TMYX attenuates myocardial NR after ischemia and reperfusion by activating the cAMP/PKA and NO/cGMP signaling pathways, further upregulating NO activity and relaxing coronary microvessels.
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http://dx.doi.org/10.1016/j.jep.2020.113462DOI Listing
March 2021

Delivery of dimethyloxalylglycine in calcined bone calcium scaffold to improve osteogenic differentiation and bone repair.

Biomed Mater 2020 Oct 6. Epub 2020 Oct 6.

Department of Orthopaedics, Fourth medical center of PLA General Hospital, Beijing, CHINA.

As hypoxia plays a vital role in the angiogenic-osteogenic coupling, using proline hydroxylase inhibitors to manipulate hypoxia-inducible factors has become a strategy to improve the osteogenic properties of biomaterials. Dimethyloxallyl glycine (DMOG) is a 2-ketoglutarate analog, a small molecular compound that competes for 2-ketoglutaric acid to inhibit proline hydroxylase. In order to improve the osteogenic ability of calcined bone calcium (CBC), a new hypoxia-mimicking scaffold (DMOG/Collagen/CBC) was prepared by immersing it in the DMOG-Collagen solution, followed by freeze-drying. All coated CBC scaffolds retained the inherent natural porous architecture and showed excellent biocompatibility. A slow release of DMOG by the DMOG-loaded CBC scaffolds for up to one week was observed in in vitro experiments. Moreover, the DMOG/Collagen/CBC composite scaffold was found to significantly stimulate bone marrow stromal cells to express osteogenic and angiogenic genes in vitro. In addition, the osteogenic properties of three kinds of scaffolds, raw CBC, Collagen/CBC, and DMOG/Collagen/CBC, were evaluated by histology using the rabbit femoral condyle defect model. Histomorphometric analyses showed that the newly formed bone (BV/TV) in the DMOG/Collagen/CBC group was significantly higher than that of the Collagen/CBC group. However, immunostaining of CD31 and Runx2 expression between these two groups showed no significant difference at this time point. Our results indicate that DMOG-coated CBC can promote osteogenic differentiation and bone healing, and show potential for clinical application in bone tissue engineering.
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http://dx.doi.org/10.1088/1748-605X/abbec7DOI Listing
October 2020

A computational model-based study on the exchangeability of hepatic venous pressure gradients measured in multiple hepatic veins.

Med Eng Phys 2020 10 30;84:28-35. Epub 2020 Jul 30.

CHESS Center, Institute of Portal Hypertension, The First Hospital of Lanzhou University, Lanzhou 73000, China.

Hepatic venous pressure gradient (HVPG) is a hemodynamic index widely used for evaluating the severity of portal hypertension. Theoretically, HVPG can be measured in any of the three major (i.e., right, middle and left) hepatic veins (HVs); however, it remains unclear whether HVPGs measured in different HVs are exchangeable, and if not, what factors cause inter-HV HVPG differences? In consideration of the potential limitations of invasive in vivo measurements, we employed a computational model implemented in conjunction with stochastic parameter sampling to simulate and compare HVPG measurements in multiple HVs under various sinusoidal portal hypertensive conditions. Results demonstrated that HVPGs measured in the right and middle HVs were basically exchangeable, whereas those in the left HV were relatively lower due primarily to the smaller proportion of hepatic venous flow through the left HV compared with that through the right or middle HV. Moreover, it was found that hepatic vein-to-vein shunts (HVVS) led to a marked augmentation of inter-HV HVPG differences and significant underestimation of portal pressure gradient with HVPG. These findings suggest that understanding the distribution of hepatic venous flow and status of HVVS is essential for selecting a proper HV for implementing HVPG measurement in clinical practice.
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http://dx.doi.org/10.1016/j.medengphy.2020.07.022DOI Listing
October 2020