Time filter

Source Type

Chen Q.,Peking Union Medical College | Deng T.,Chinese Institute of Clinical Medical Sciences | Han D.,Peking Union Medical College
Seminars in Cell and Developmental Biology | Year: 2016

The mammalian testis possesses a unique immune environment that is essential for testicular function. The testis is a remarkable immunoprivileged site that protects immunogenic germ cells from the detrimental effects of immune responses. However, the testis can be infected by various microbial pathogens. To overcome the immune privilege and enable testicular defense against microbes, the testis adopts local effective innate immune responses to microbial infections. The mechanisms underlying the testicular immune privilege have been investigated for several decades and the innate defense system in the testis is being revealed based on the identification of pattern recognition receptor-initiated innate immune responses in testicular cells. The coordination between immune privilege and local innate immune responses is critical in the maintenance of testicular immune homeostasis. Disruption of the testicular immune homeostasis may lead to orchitis and impair spermatogenesis, an etiological factor of male infertility. Dissection of the immunoregulatory mechanisms in the testis can aid in establishing preventive and therapeutic approaches for orchitis. This review discusses current understanding of the mechanisms which underlie the testicular immunoregulation and its effect on spermatogenesis. © 2016 Elsevier Ltd. Source

Xia Q.S.,Chinese Institute of Clinical Medical Sciences
Zhonghua yi xue za zhi | Year: 2010

OBJECTIVE: To investigate the effect of anti-cancer drugs on the expression of B-cell integration cluster (BIC) RNA/miRNA-155 in human pancreatic cancer PANC-1 cells. METHODS: PANC-1 cells were treated with different concentrations of anti-cancer drugs. Total RNA of the treated cells were harvested and the expression levels of BIC RNA and mature miR-155 were quantified by using Taqman FAM/MGB probes on a real-time PCR system. Relative quantification was carried out using the DeltaDeltaCt method. A PI3K-related kinases inhibitor was used to determine whether these kinases were involved in the regulation of BIC RNA. RESULTS: The expression of BIC RNA was strongly induced by anti-cancer drugs. When PANC-1 cells were treated by gemcitabine with concentrations of 1.0, 2.5, 5.0, 10.0 mg/L for 48 h and 72 h, the level of BIC RNA (48 h: 37.1 +/- 4.1, 29.0 +/- 5.7, 21.0 +/- 7.6, 40.4 +/- 9.0, 72 h: 27.7 +/- 3.1, 43.1 +/- 1.2, 31.8 +/- 5.4, 23.1 +/- 1.4) were significantly higher than that of the control (48 h: 1.6 +/- 1.1, 72 h: 1.0 +/- 0.1, all P < 0.05). 5-FU (10 mg/L, 48 h) and bleomycin (100 mg/L, 48 h) also induced BIC RNA up-regulation (5.2 +/- 1.1 vs 1.7 +/- 0.7, 11.5 +/- 0.7 vs 1.7 +/- 0.7, both P < 0.05). When PANC-1 cells treated with 1.0, 2.5, 5.0, 10.0 mg/L gemcitabine for 72 h, the level of miR-155 (2.21 +/- 0.40, 1.86 +/- 0.03, 2.47 +/- 0.04, 3.24 +/- 0.05) also higher than that of the control (1.11 +/- 0.09, P < 0.05), while no change was observed when the cells only treated for 48 h. Further study showed gemcitabine-induced BIC RNA up-regulation was inhibited by wortmannin, a specific PI3K inhibitor, the expression levels of BIC RNA of 1 micromol/L wortmannin + 5 mg/L gemcitabine group and 10 micromol/L wortmannin + 5 mg/L gemcitabine group were 5.34 +/- 1.11 and 1.26 +/- 0.07, lower than that of 5 mg/L gemcitabine group (11.82 +/- 3.11, P < 0.05). CONCLUSIONS: BIC RNA is strongly induced by anti-cancer drugs in PANC-1 cells and the levels of miR-155 also slightly increase. PI3K pathway is involved in gemcitabine-induced BIC RNA up-regulation. Source

D'Ascenzo F.,Chinese Institute of Clinical Medical Sciences
Journal of Cardiovascular Medicine | Year: 2016

BACKGROUND: Bleeding events after an acute coronary syndrome have a negative impact on prognosis. Available risk scores are limited by suboptimal accuracy, prediction of only in-hospital events and absence of patients treated with new antiplatelet agents in the current era of widespread use of percutaneous coronary intervention. DESIGN: The BleeMACS (Bleeding complications in a Multicenter registry of patients discharged after an Acute Coronary Syndrome) project is a multicenter investigator-initiated international retrospective registry that enrolled more than 15?000 patients discharged with a definitive diagnosis of acute coronary syndrome and treated with percutaneous revascularization. The primary end point is the incidence of major bleeding events requiring hospitalization and/or red cell transfusion concentrates within 1 year. An integer risk score for bleeding within the first year after hospital discharge will be developed from a multivariate competing-risks regression. CONCLUSION: The BleeMACS registry collaborative will allow development and validation of a risk score for prediction of major bleeding during follow-up for patients receiving contemporary therapies for acute coronary syndrome. Copyright © 2016 Wolters Kluwer Health, Inc. All rights reserved. Source

He H.,CAS Beijing National Laboratory for Molecular | Li Y.,CAS Beijing National Laboratory for Molecular | Jia X.-R.,CAS Beijing National Laboratory for Molecular | Du J.,Peking University | And 4 more authors.
Biomaterials | Year: 2011

A dual-targeting drug carrier (PAMAM-PEG-WGA-Tf) based on the PEGylated fourth generation (G = 4.0) PAMAM dendrimer with transferrin (Tf) and wheat germ agglutinin (WGA) on the periphery and doxorubicin (DOX) loaded in the interior was synthesized and its BBB penetration and tumor targeting properties were explored. DLS and TEM measurements revealed the size of PAMAM-PEG-WGA-Tf was in the range of 14-20 nm. It reduced the cytotoxicity of DOX to the normal cells greatly, while efficiently inhibited the growth rate of the C6 glioma cells. The assay of transport across the BBB showed that PAMAM-PEG-WGA-Tf delivered 13.5% of DOX in a period of 2 h, demonstrating an enhanced transport ratio as compared to the ratio of 8% for PAMAM-PEG-WGA, 7% for PAMAM-PEG-Tf and 5% for free DOX in the same period of time. The accumulation of DOX in the tumor site was increased due to the targeting effects of both Tf and WGA, leading to the complete breakage of the avascular C6 glioma spheroids in vitro. © 2010 Elsevier Ltd. Source

Li Y.,CAS Beijing National Laboratory for Molecular | He H.,CAS Beijing National Laboratory for Molecular | Jia X.,CAS Beijing National Laboratory for Molecular | Lu W.-L.,Peking University | And 2 more authors.
Biomaterials | Year: 2012

A pH-sensitive dual-targeting drug carrier (G4-DOX-PEG-Tf-TAM) was synthesized with transferrin (Tf) conjugated on the exterior and Tamoxifen (TAM) in the interior of the fourth generation PAMAM dendrimers for enhancing the blood-brain barrier (BBB) transportation and improving the drug accumulation in the glioma cells. It was found that, on average, 7 doxorubicine (DOX) molecules, over 30 PEG 1000 and PEG 2000 chains and one Tf group were bonded on the periphery of each G4 PAMAM dendrimer, while 29 TAM molecules were encapsulated into the interior of per dendrimer. The pH-triggered DOX release was 32% at pH 4.5 and 6% at pH 7.4, indicating a comparatively fast drug release at weak acidic condition and stable state of the carrier at physiological environment. The in vitro assay of the drug transport across the BBB model showed that G4-DOX-PEG-Tf-TAM exhibited higher BBB transportation ability with the transporting ratio of 6.06% in 3 h. The carrier was internalized into C6 glioma cells upon crossing the BBB model by the coactions of TfR-mediated endocytosis and the inhibition effect of TAM to the drug efflux transports. Moreover, it also displayed the in vitro accumulation of DOX in the avascular C6 glioma spheroids made the tumor volume effectively reduced. © 2012 Elsevier Ltd. Source

Discover hidden collaborations