Yuzhong Chengguanzhen, China

Chongqing Medical University

Yuzhong Chengguanzhen, China

Chongqing Medical University , previously referred to as the Chongqing University of Medical science , was established in 1956 in Chongqing, China. It was originally a branch of the Shanghai First Medical College . Wikipedia.

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Considerable evidences have shown that autophagy has an important role in tumor chemoresistance. However, it is still unknown whether the lncRNA HULC (highly upregulated in liver cancer) is involved in autophagy and chemoresistance of hepatocellular carcinoma (HCC). In this study, we for the first time demonstrated that treatment with antitumor reagents such as oxaliplatin, 5-fluorouracil and pirarubicin (THP) dramatically induced HULC expression and protective autophagy. Silencing of HULC sensitized HCC cells to the three antitumor reagents via inhibiting protective autophagy. Ectopic expression of HULC elicited the autophagy of HCC cells through stabilizing silent information regulator 1 (Sirt1) protein. The investigation for the corresponding mechanism by which HULC stabilized Sirt1 revealed that HULC upregulated ubiquitin-specific peptidase 22 (USP22), leading to the decrease of ubiquitin-mediated degradation of Sirt1 protein by removing the conjugated polyubiquitin chains from Sirt1. Moreover, we found that miR-6825-5p, miR-6845-5p and miR-6886-3p could decrease the level of USP22 protein by binding to the 3′-untranlated region of USP22 mRNA. All the three microRNAs (miRNAs) were downregulated by HULC, which resulted in the elevation of USP22. In addition, we showed that the level of HULC was positively correlated with that of Sirt1 protein in human HCC tissues. Collectively, our data reveals that the pathway ‘HULC/USP22/Sirt1/ protective autophagy’ attenuates the sensitivity of HCC cells to chemotherapeutic agents, suggesting that this pathway may be a novel target for developing sensitizing strategy to HCC chemotherapy.Oncogene advance online publication, 6 February 2017; doi:10.1038/onc.2016.521. © 2017 Macmillan Publishers Limited, part of Springer Nature.

Zhang J.,Chongqing Medical University | Ma P.X.,University of Michigan
Advanced Drug Delivery Reviews | Year: 2013

The excellent biocompatibility and unique inclusion capability as well as powerful functionalization capacity of cyclodextrins and their derivatives make them especially attractive for engineering novel functional materials for biomedical applications. There has been increasing interest recently to fabricate supramolecular systems for drug and gene delivery based on cyclodextrin materials. This review focuses on state of the art and recent advances in the construction of cyclodextrin-based assemblies and their applications for controlled drug delivery. First, we introduce cyclodextrin materials utilized for self-assembly. The fabrication technologies of supramolecular systems including nanoplatforms and hydrogels as well as their applications in nanomedicine and pharmaceutical sciences are then highlighted. At the end, the future directions of this field are discussed. © 2013 Elsevier B.V.

BACKGROUND—: Adult mammalian hearts have a limited ability to generate new cardiomyocytes. Proliferation of existing adult cardiomyocytes (ACM) is a potential source of new cardiomyocytes. Understanding the fundamental biology of ACM proliferation could be of great clinical significance for treating myocardial infarction (MI). We aim to understand the process and regulation of ACM proliferation and its role in new cardiomyocyte formation of post-MI mouse hearts. METHODS—: β-actin-GFP transgenic mice and fate-mapping Myh6-MerCreMer-tdTomato/lacZ mice were used to trace the fate of ACMs. In a co-culture system with neonatal rat ventricular myocytes (NRVMs), ACM proliferation was documented with clear evidence of cytokinesis observed with time-lapse imaging. Cardiomyocyte proliferation in the adult mouse post-MI heart was detected by cell cycle markers and EdU incorporation analysis. Echocardiography was used to measure cardiac function and histology was performed to determine infarction size. RESULTS—: In-vitro, mononucleated and bi/multi-nucleated ACMs were able to proliferate at a similar rate (7.0%) in the co-culture. Dedifferentiation proceeded ACM proliferation, which was followed by redifferentiation. Redifferentiation was essential to endow the daughter cells with cardiomyocyte contractile function. Intercellular propagation of Ca2+ from contracting NRVMs into ACM daughter cells was required to activate the Ca2+ dependent calcineurin-nuclear factor of activated T cells signaling pathway to induce ACM redifferentiation. The properties of NRVM Ca2+ transients influenced the rate of ACM redifferentiation. Hypoxia impaired the function of gap junctions by dephosphorylating its component protein connexin 43, the major mediator of intercellular Ca2+ propagation between cardiomyocytes, thereby impairing ACM redifferentiation. In-vivo, ACM proliferation was found primarily in the MI border zone. An ischemia resistant connexin 43 mutant enhanced the redifferentiation of ACM-derived new cardiomyocytes after MI and improved cardiac function. CONCLUSIONS—: Mature ACMs can reenter the cell cycle and form new cardiomyocytes through a three-step process, dedifferentiation, proliferation and redifferentiation. Intercellular Ca2+ signal from neighboring functioning cardiomyocytes through gap junctions induces the redifferentiation process. This novel mechanism contributes to new cardiomyocyte formation in post-MI hearts in mammals. © 2017 by the American College of Cardiology Foundation and the American Heart Association, Inc.

The cerebellum plays an essential role in motor learning. Recently, orexins, the newfound lateral hypothalamic neuropeptides, have been found to excite Purkinje cells in the cerebellar cortex and neurons in the deep cerebellar nuclei (DCN). However, little is known about their roles in cerebellum-dependent motor learning. Therefore, the present study was designed to investigate the functional significance of hypothalamic orexinergic system during trace eyeblink conditioning, a tractable behavioral model system of cerebellum-dependent motor learning. It was revealed that the orexin 1 receptors (OXR1) were specifically localized on the soma of Purkinje cells and large DCN neurons. Furthermore, interfering with the endogenous orexins' effects on the cerebellum via the selective OXR1 antagonist SB-334867 disrupted the timing rather than the acquisition of trace conditioned eyeblink responses. In addition to the behavioral effects, the SB-334867 prevented the increase in peak amplitude of cerebellar theta oscillations with learning. These results suggest that the endogenous orexins may modulate motor learning via the activation of cerebellar OXR1. Copyright © 2013 Elsevier B.V. All rights reserved.

Xiong X.-Y.,Chongqing Medical University | Liu L.,Chongqing Medical University | Yang Q.-W.,Chongqing Medical University
Progress in Neurobiology | Year: 2016

Microglia/macrophages are the major immune cells involved in the defence against brain damage. Their morphology and functional changes are correlated with the release of danger signals induced by stroke. These cells are normally responsible for clearing away dead neural cells and restoring neuronal functions. However, when excessively activated by the damage-associated molecular patterns following stroke, they can produce a large number of proinflammatory cytokines that can disrupt neural cells and the blood-brain barrier and influence neurogenesis. These effects indicate the important roles of microglia/macrophages in the pathophysiological processes of stroke. However, the modifiable and adaptable nature of microglia/macrophages may also be beneficial for brain repair and not just result in damage. These distinct roles may be attributed to the different microglia/macrophage phenotypes because the M1 population is mainly destructive, while the M2 population is neuroprotective. Additionally, different gene expression signature changes in microglia/macrophages have been found in diverse inflammatory milieus. These biofunctional features enable dual roles for microglia/macrophages in brain damage and repair. Currently, it is thought that the proper inflammatory milieu may provide a suitable microenvironment for neurogenesis; however, detailed mechanisms underlying the inflammatory responses that initiate or inhibit neurogenesis remain unknown. This review summarizes recent progress concerning the mechanisms involved in brain damage, repair and regeneration related to microglia/macrophage activation and phenotype transition after stroke. We also argue that future translational studies should be targeting multiple key regulating molecules to improve brain repair, which should be accompanied by the concept of a "therapeutic time window" for sequential therapies. © 2016 Elsevier Ltd.

Wang G.,Chongqing Medical University | Wu G.,University of Georgia
Trends in Pharmacological Sciences | Year: 2012

The physiological functions of heterotrimeric G protein-coupled receptors (GPCRs) are dictated by their intracellular trafficking and precise targeting to the functional destinations. Over the past decades, most studies on the trafficking of GPCRs have focused on the events involved in endocytosis and recycling. By contrast, the molecular mechanisms underlying anterograde transport of newly synthesized GPCRs from the endoplasmic reticulum (ER) to the cell surface have only now begun to be revealed. In this review we discuss current advances in understanding the role of Ras-like GTPases, specifically the Rab and Sar1/ARF subfamilies, in regulating cell-surface transport of GPCRs en route from the ER and the Golgi. © 2011 Elsevier Ltd. All rights reserved.

Luo Z.,Chongqing Medical University | Zhang S.,Massachusetts Institute of Technology
Chemical Society Reviews | Year: 2012

Chirality is absolutely central in chemistry and biology. The recent findings of chiral self-assembling peptides' remarkable chemical complementarity and structural compatibility make it one of the most inspired designer materials and structures in nanobiotechnology. The emerging field of designer chemistry and biology further explores biological and medical applications of these simple d,l- amino acids through producing marvellous nanostructures under physiological conditions. These self-assembled structures include well-ordered nanofibers, nanotubes and nanovesicles. These structures have been used for 3-dimensional tissue cultures of primary cells and stem cells, sustained release of small molecules, growth factors and monoclonal antibodies, accelerated wound-healing in reparative and regenerative medicine as well as tissue engineering. Recent advances in molecular designs have also led to the development of 3D fine-tuned bioactive tissue culture scaffolds. They are also used to stabilize membrane proteins including difficult G-protein coupled receptors for designing nanobiodevices. One of the self-assembling peptides has been used in human clinical trials for accelerated wound-healings. It is our hope that these peptide materials will open doors for more and diverse clinical uses. The field of chiral self-assembling peptide nanobiotechnology is growing in a number of directions that has led to many surprises in areas of novel materials, synthetic biology, clinical medicine and beyond. © 2012 The Royal Society of Chemistry.

To identify new genetic risk factors for Vogt-Koyanagi-Harada (VKH) syndrome, we conducted a genome-wide association study of 2,208,258 SNPs in 774 cases and 2,009 controls with follow-up in a collection of 415 cases and 2,006 controls and a further collection of 349 cases and 1,588 controls from a Han Chinese population. We identified three loci associated with VKH syndrome susceptibility (IL23R-C1orf141, rs117633859, Pcombined = 3.42 × 10-21, odds ratio (OR) = 1.82; ADO-ZNF365-EGR2, rs442309, Pcombined = 2.97 × 10-11, OR = 1.37; and HLA-DRB1/DQA1, rs3021304, Pcombined = 1.26 × 10-118, OR = 2.97). The five non-HLA genes were all expressed in human iris tissue. IL23R was also expressed in the ciliary body, and EGR2 was expressed in the ciliary body and choroid. The risk G allele of rs117633859 in the promoter region of IL23R exhibited low transcriptional activation in a cell-based reporter assay and was associated with diminished IL23R mRNA expression in human peripheral blood mononuclear cells.

Highly charged hydrophilic superparamagnetic Fe3O4 colloidal nanocrystal clusters with an average diameter of 195 nm have been successfully synthesized using a modified one-step solvothermal method. Anionic polyelectrolyte poly(4-styrenesulfonic acid-co-maleic acid) sodium salt containing both sulfonate and carboxylate groups was used as the stabilizer. The clusters synthesized under different experimental conditions were characterized with transmission electron microscopy and dynamic light scattering; it was found that the size distribution and water dispersity were significantly affected by the concentration of the polyelectrolyte stabilizer and iron sources in the reaction mixtures. A possible mechanism involving novel gel-like large molecular networks that confined the nucleation and aggregation process was proposed and discussed. The colloidal nanocrystal clusters remained negatively charged in the experimental pH ranges from 2 to 11, and also showed high colloidal stability in phosphate buffered saline (PBS) and ethanol. These highly colloidal stable superparamagnetic Fe3O4 clusters could find potential applications in bioseparation, targeted drug delivery, and photonics.

Fang J.,Chongqing Medical University
Investigative ophthalmology & visual science | Year: 2013

TLR2, TLR4, TLR8, and TLR9 have been reported to be associated with several autoimmune diseases. The current study aimed to explore whether singe nucleotide polymorphisms (SNPs) of these four genes were associated with ocular Behçet's disease (BD), Vogt-Koyanagi-Harada (VKH) syndrome, acute anterior uveitis (AAU) with or without ankylosing spondylitis (AS), or pediatric uveitis in Han Chinese. Genotyping was performed by PCR-restriction fragment length polymorphism. The first stage study comprised 400 ocular BD patients, 400 VKH syndrome patients, 400 AAU ± AS patients, 400 pediatric uveitis patients and 600 healthy subjects. The second stage included 438 ocular BD patients and 1000 healthy subjects. Allele and genotype frequencies were compared between patients and controls using the χ(2) test. Real-time PCR was used to detect mRNA expression from PBMCs obtained from healthy controls. Levels of TNF-α, IL-6, IL-10, and IL-1beta in culture supernatants were measured by ELISA. In the first stage study, only the frequencies of the rs2289318/TLR2 genotype A and C allele and rs3804099/TLR2 genotype CT were significantly higher in ocular BD patients (Pc = 0.048; Pc = 0.008; Pc = 0.005, respectively) compared with controls. The second stage and combined studies confirmed the association (Pc = 0.001; Pc = 6.89E-06, Pc = 2.426E-06, respectively). TLR2 mRNA expression in PBMCs was increased in healthy carriers of the CC genotype of rs2289318/TLR2 and TT genotype of rs3804099/TLR2 following stimulation with peptidoglycan (PGN; P = 0.028; P = 0.004, respectively). No effect of the various TLR2 rs2289318 and rs3804099 genotypes on the release of TNF-α, IL-6, IL-10, and IL-1beta could be detected. This study provides evidence that the TLR2 gene is involved in the susceptibility to ocular BD.

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