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Deng S.,University of Birmingham | Penchev P.,University of Birmingham | Liu J.,Sichuan UniversitySichuan | Wang Y.,University of Birmingham | And 6 more authors.
Nanoscale | Year: 2015

Laser directed patterning of carbon nanotubes-based buckypaper for producing a diffractive optical device is presented here. Using a laser ablation method the buckypaper was patterned into a binary Fresnel zone plate lens. Computational modelling was performed which revealed excellent focusing performance of the lens for both visible and THz radiations. SEM and Raman measurements of the lens were studied to analyse the laser-material interaction. The focusing properties of the lens were characterized and a good agreement with the simulations was achieved. Hence, we exploited a new way to fabricate thin flat lens. The one-step fabrication process is economical, convenient and has great potential for industrial scale up. This journal is © The Royal Society of Chemistry.

Xu X.,University of Maryland Institute for Bioscience and Biotechnology Research | Xu X.,Sichuan UniversitySichuan | Narni-Mancinelli E.,Aix - Marseille University | Cantoni C.,University of Genoa | And 15 more authors.
Journal of Molecular Biology | Year: 2016

Antibodies have been shown to block signaling through cell surface receptors using several mechanisms. The two most common are binding to the ligand-binding site of the receptor and, conversely, binding to the receptor-binding site of the ligand. Here, we investigated the inhibitory mechanism of an antibody (17B1.3) against human B7-H6, a stress-induced cellular ligand for the natural killer (NK) cell receptor NKp30. Binding of this antibody to B7-H6, a transmembrane protein expressed on tumor and other stressed cells, but not on normal cells, prevents NK cell activation via NKp30. We determined the crystal structure of antibody 17B1.3 in complex with the ectodomain of B7-H6 to 2.5 Å resolution. Surprisingly, 17B1.3 binds to a site on B7-H6 that is completely distinct from the binding site for NKp30, such that 17B1.3 does not block the NKp30–B7-H6 interaction. We then asked whether 17B1.3 prevents signaling by binding to a putative site for B7-H6 dimerization. However, structure-based mutations designed to disrupt potential B7-H6 dimerization through this site did not diminish NKp30-mediated cell activation. We conclude that the bulky 17B1.3 antibody most likely acts by sterically interfering with close cell–cell contacts at the NK cell–target cell interface that are required for NK cell activation. A similar inhibitory mechanism may apply to other antibodies, including therapeutic antibodies that block signaling through cell surface receptors whose ligands are also cell surface proteins. © 2016 Elsevier Ltd

Li W.,Sichuan UniversitySichuan | Peng J.,Sichuan UniversitySichuan | Tan L.,Sichuan UniversitySichuan | Wu J.,Sichuan UniversitySichuan | And 4 more authors.
Biomaterials | Year: 2016

Patients suffering from cancer have benefited from combination therapy. Nanocarriers are the ideal candidates for combination therapy. In this study, we constructed docetaxel (DTX) loaded micellar nanomedicines co-loaded with near infrared (NIR) dye-IR820 for photothermal therapy (PTT)/photodynamic therapy (PDT)/chemotherapy of breast cancer. Lyp-1, a tumor homing peptide, was introduced into the nanosystems to construct the active targeting nanomedicine. In order to deliver IR820 to the tumor site and overcome its short lifetime in vivo, a PEI derivative—PCL-g-PEI was introduced. IR820 with negative charge was formed stable static interaction with the amine groups, meanwhile, the absorption of IR820 in the NIR region was weakened. It indicated that the nanosystem constructed in this study may provide an alternative candidate for mild PTT. By the evaluation of the photothermal conversion in vivo, we can confirm that IR820 has been successfully delivered and effectively accumulated in the tumor site. Furthermore, the tumor cells targeting and anticancer performances of this nanosystem have been studied in vitro and in vivo. The results demonstrated Lyp-1 modification has enhanced the tumor targeting delivery of DTX and IR820. By combining PTT and PDT, DTX nanomedicine efficiently inhibited the growth and metastasis of breast cancer in mice. This nanosystem is a promising candidate for combination therapy of breast cancer. © 2016 Elsevier Ltd

Jiang X.,Sichuan UniversitySichuan | Wang Q.,Sichuan UniversitySichuan | Huang R.,Sichuan UniversitySichuan
Clinical Nuclear Medicine | Year: 2015

Nasal iodine activity can be observed on 123Iodine (123I) or 131I wholebody scintigraphy (WBS) commonly as a normal variant caused by nasal or salivary secretion of the tracer. We encountered 2 patients whose increased accumulation of 131I activity was associated with underlying abnormalities. One patient had a nasal polyp, whereas the other had an abscess. Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.

Guo Y.,University of Sichuan | Wei C.,University of Sichuan | Liu C.,University of Sichuan | Li D.,University of Sichuan | And 4 more authors.
Archives of Oral Biology | Year: 2015

Objective The pathogenesis of Candida-associated stomatitis involves the dysfunction of flora antagonistic to Candida. Oral Actinomyces species play an important role in regulating the oral microecological balance. The objective of this study was to investigate the antagonism of three oral Actinomyces against Candida albicans. Design Suspensions, culture supernatants and bacterial lysates of Actinomyces viscosus, Actinomyces naeslundii and Actinomyces odontolyticus were investigated for their actions upon C. albicans. In addition to a commercial strain, six clinical strains of C. albicans were also tested. The proliferation of C. albicans was assessed using a liquid co-cultivation assay. The adhesion, acid protease and extracellular phospholipase activity, hyphae growth, and biofilm formation of C. albicans were measured. Results The results showed that the suspensions, culture supernatants and cell lysates of 108 colony forming units/ml oral Actinomyces significantly inhibited the proliferation of C. albicans (all P < 0.001). The culture supernatants exhibited significant antagonistic interactions in terms of adhesion (A. viscosus P < 0.001, A. naeslundii P = 0.016 and A. odontolyticus P = 0.009), acid protease (A. viscosus P = 0.035, A. naeslundii P = 0.022, A. odontolyticus P < 0.001) and phospholipase activities (A. viscosus P = 0.011, A. naeslundii P = 0.042, A. odontolyticus P = 0.021) of Candida, as well as its hyphae growth (A. viscosus P = 0.002, A. naeslundii P = 0.008, A. odontolyticus P = 0.006). Inhibition of C. albicans biofilm formation was also observed. Conclusions This study provides preliminary evidence that oral Actinomyces have inhibitory effects on the proliferation, adhesion, metabolic enzyme activity, hyphae formation and biofilm development of C. albicans. © 2015 Elsevier Ltd. All rights reserved.

Wang Y.,Sichuan UniversitySichuan | Qiao Y.,Sichuan UniversitySichuan | Li W.,Sichuan UniversitySichuan
International Journal of Clinical and Experimental Medicine | Year: 2016

Objectives: To investigate the predictive value of computed tomography imaging in diagnosis of extratemporal facial nerve schwannoma. Materials and methods: Computed tomography records of eight patients with extratemporal facial nerve schwannoma managed from 2007~2015 were reviewed. Tumors of all cases were totally removed surgically. Intraoperative frozen section examination was employed. Results: computed tomography of one patient whose tumor derived from buccal branch demonstrated imaging of a round mass with clear margin; four out of five patients whose tumors derived from facial nerve trunk revealed a significant tail pointing to the stylomastoid foramen with one exception; one patient whose tumor located at the margin of parotid gland demonstrated round mass just outside the stylomastoid foramen deep to the mastoid process with a tail pointing to the parotid gland; one case of synchronous schwannomas took place in the parotid gland and parapharyngeal space presented obscure tail-like imaging. Diagnoses of schwannoma were inclined in all intraoperative frozen section examinations. There was no tumor relapse in all cases after one to three years follow-up while the tumor-involved facial nerve or nerve branches were disturbed in all cases. Conclusion: Computed tomography findings can provide some useful information for the diagnosis of extratemporal facial nerve schwannoma especially for those derived from nerve trunk. © 2016, E-Century Publishing Corporation. All rights reserved.

Cheng L.,Sichuan UniversitySichuan | Tang X.,Sichuan UniversitySichuan | Fu P.,Sichuan UniversitySichuan | Liu F.,Sichuan UniversitySichuan
Singapore Medical Journal | Year: 2015

A 39-year-old woman with end-stage renal disease, which was maintained on haemodialysis, developed secondary haemochromatosis after receiving blood transfusions and intravenous iron supplementation without sufficient serum ferritin concentration monitoring. The patient received intravenous deferoxamine three times a week, combined with high-dose recombinant human erythropoietin therapy and haemodialysis. After three months, improvements in biochemical indicators and iron overload were noted. © 2015, Singapore Medical Association. All rights reserved.

Sun L.,West China Hospital of Sichuan UniversitySichuan | Li Y.,Sichuan UniversitySichuan | Yang B.,West China Hospital of Sichuan UniversitySichuan
Biochemical and Biophysical Research Communications | Year: 2016

Long non-coding RNAs (lncRNAs) was found to play critical roles in tumorigenesis, hence, screen of tumor-related lncRNAs, identification of their biological roles is important for understanding the processes of tumorigenesis. In this study, we identified the expressing difference of several tumor-related lncRNAs in breast cancer samples and found that, MEG3, which is downregulated in non-small cell lung cancer (NSCLC) tumor tissues, is also downregulated in breast cancer samples compared with adjacent tissues. For figuring out the effect of MEG3 in breast cancer cells MCF7 and MB231, we overexpressed MEG3 in these cells, and found that it resulted the inhibition of proliferation, colony formation, migration and invasion capacities by enhancing p53’s transcriptional activity on its target genes, including p21, Maspin and KAI1. MEG3 presented similar effects in MB157, which is a p53-null breast cancer cell line, when functional p53 but not p53R273H mutant, which lacks transcriptional activity, was introduced. Surprisingly, overexpression of MEG3 activates p53’s transcriptional activity by decreasing MDM2’s transcription level, and thus stabilizes and accumulates P53. Taken together, our findings indicate that MEG3 is downregulated in breast cancer tissues and affects breast cancer cells’ malignant behaviors, which indicate MEG3 a potential therapeutic target for breast cancer. © 2016

Chen J.,Sichuan Orthopedic HospitalSichuan | Chen J.,Sichuan UniversitySichuan | Xiao J.,Sichuan UniversitySichuan
International Journal of Clinical and Experimental Medicine | Year: 2015

The purpose of our study was to accurately visualize and measure the normal anatomy and size of the pterygoid canal with thin-section (0.5 mm), high-resolution computed tomography (HRCT) as well as multiplanar reconstruction (MPR) and curved planar reconstruction (CPR) technologies to obtain credible and comprehensive information for clinical management. Both axial HRCT and MPR images of the pterygopalatine fossa were obtained in 167 normal adult subjects, who exhibited variable positions of pterygoid canal relative to the sphenoid sinus floor and cavity. The morphology and size of the pterygoid canal was observed and measured, respectively. All pterygoid canals (100%, 334/334) were well delineated on HRCT images. Statistical analyses showed no significant difference between the mean length of the left (12.6 ± 2.3 mm) and right pterygoid canals (12.5 ± 2.9 mm) (P = 0.405). The mean diameter of anterior, median and posterior opening of the left and right pterygoid canals exhibited no significant differences (all P > 0.05); the bilateral median opening possessed the smallest diameter (P < 0.001). Submillimeter, thin-section HRCT scan and appropriate postprocessing reconstruction technologies could clearly visualize the morphologic features of the pterygoid canal and adjacent structures, which may be helpful for making diagnostic and therapeutic decisions. © 2015, E-Century Publishing Corporation. All rights reserved.

Lin X.-D.,University of Sichuan | Yang H.-W.,University of Sichuan | Ma S.,University of Sichuan | Li W.-W.,University of Sichuan | And 5 more authors.
Bioorganic and Medicinal Chemistry Letters | Year: 2015

In this investigation, a series of 6-phenylimidazo[2,1-b]thiazole derivatives were synthesized. Structure-activity relationship (SAR) analysis of these compounds based on cellular assays led to the discovery of a number of compounds that showed potent activity against FLT3-dependent human acute myeloid leukemia (AML) cell line MV4-11, but very weak or no activity against FLT3-independent human cervical cancer cell line Hela. FLT3 kinase inhibition assays were then performed on the three most active compounds. Among these compounds, 6-(4-(3-(5-(tert-butyl)isoxazol- 3-yl)ureido)phenyl)-N-(3-(dimethylamino)propyl)imidazo[2,1-b]thiazole-3-carboxamide (19) exhibited the highest potency in both cellular (MV4-11, IC50: 0.002 μM) and enzymatic (FLT3, IC50: 0.022 μM) assays. Further in-depth in vitro anti-AML activity and mechanism of action studies were carried out on compound 19. © 2015 Elsevier Ltd.

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