Shared posts

09 May 07:48

[Editorial] Don't ignore the infrastructure

by Alan I. Leshner
Large-scale research facilities and new technology development have been essential to answering difficult, often intransigent scientific questions that would otherwise be inaccessible. The recent exciting discovery of gravitational waves by the Laser Interferometer Gravitational-Wave Observatory (LIGO) is but one of many startling findings that argue for major investments in large- and mid-scale instrumentation development. But such instruments and facilities are just one type of infrastructure that urgently needs investment. Routine laboratories that underpin most scientific activity are equally critical to progress, but in many cases have long been neglected and are deteriorating. A comprehensive strategy for updating these facilities and other infrastructure elements is essential for accelerating scientific momentum. Author: Alan I. Leshner
05 May 01:55

[Editorial] My love-hate of Sci-Hub

by Marcia McNutt
Like many scientist-editors of journals published by nonprofit scientific societies, I have a love-hate relationship with Sci-Hub, the website operated out of Russia that provides access to 50 million pirated scientific articles to researchers worldwide (see the News story on p. 508). I recognize the underlying motivation of bringing global research content to the developing world. However, I also recognize that much traffic to Sci-Hub is from researchers who already have access to the articles they seek through mechanisms such as site licenses, open access, or other means. Authors who publish in Science journals, for example, can make their papers available immediately upon publication through free referrer links at the authors' websites. Research published after 1996 in a Science journal is made free with registration 1 year after its publication date. So what does the scientific community risk by gathering papers illegally? Author: Marcia McNutt
19 Apr 08:46

Delivery of oncolytic adenovirus into the nucleus of tumorigenic cells by tumor microparticles for virotherapy

Publication date: May 2016
Source:Biomaterials, Volume 89
Author(s): Li Ran, Xiaohua Tan, Yanchun Li, Huafeng Zhang, Ruihua Ma, Tiantian Ji, Wenqian Dong, Tong Tong, Yuying Liu, Degao Chen, Xiaonan Yin, Xiaoyu Liang, Ke Tang, Jingwei Ma, Yi Zhang, Xuetao Cao, Zhuowei Hu, Xiaofeng Qin, Bo Huang
Oncolytic viruses have been utilized for the treatment of various cancers. However, delivery of the viral particles to tumor cells remains a major challenge. Microparticles (MP) are vesicle forms of plasma membrane fragments of 0.1–1 μm in size that are shed by cells. We have previously shown the delivery of chemotherapeutic drugs using tumor cell-derived MPs (T-MP). Here we report that T-MPs can be utilized as a unique carrier system to deliver oncolytic adenoviruses to human tumors, leading to highly efficient cytolysis of tumor cells needed for in vivo treatment efficacy. This T-MP-mediated oncolytic virotherapy approach holds multiple advantages, including: 1) delivery of oncolytic adenovirus by T-MPs is able to avoid the antiviral effect of host antibodies; 2) delivery of oncolytic adenovirus by T-MPs is not limited by virus-specific receptor that mediates the entry of virus into tumor cells; 3) T-MPs are apt at delivering oncolytic adenoviruses to the nucleus of tumor cells as well as to stem-like tumor-repopulating cells for the desired purpose of killing them. These findings highlight a novel oncolytic adenovirus delivery system with highly promising clinical applications.

06 Aug 08:45

Understanding and exploiting nanoparticles' intimacy with the blood vessel and blood

Chem. Soc. Rev., 2015, 44,8174-8199
DOI: 10.1039/C5CS00499C, Review Article
Magdiel Inggrid Setyawati, Chor Yong Tay, Dominic Docter, Roland H. Stauber, David Tai Leong
Understanding the interaction between nanoparticles, blood and blood vessel cells for a better designed of nanomedicine.
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17 Jul 00:26

Cancer: A dendritic-cell brake on antitumour immunity

by Miriam Merad

Cancer: A dendritic-cell brake on antitumour immunity

Nature 523, 7560 (2015). doi:10.1038/523294a

Authors: Miriam Merad & Hélène Salmon

Activation of a cellular stress response and the transcription factor XBP1 in dendritic cells has now been shown to limit the cells' ability to stimulate antitumour immune responses in a mouse model of ovarian cancer.

18 Mar 13:31

Effects of Delocalized Charge Carriers in Organic Solar Cells: Predicting Nanoscale Device Performance from Morphology

by Adam G. Gagorik, Jacob W. Mohin, Tomasz Kowalewski, Geoffrey R. Hutchison

Monte Carlo simulations of charge transport in organic solar cells are performed for ideal and isotropic bulk heterojunction morphologies while altering the delocalization length of charge carriers. Previous device simulations have either treated carriers as point charges or with a highly delocalized mean-field treatment. This new model of charge delocalization leads to weakening of Coulomb interactions and more realistic predicted current and fill factors at moderate delocalization, relative to point charges. It is found that charge delocalization leads to significantly increased likelihood of escaping interface traps. In isotopic two-phase morphologies, increasing the domain sizes leads to slight decreases in predicted device efficiencies. It was previously shown that tortuous pathways in systems with small domain sizes can decrease device performance in thin film systems. However, the diminishing effects of Coulomb interactions with delocalization and efficient separations of excitons by small domains make morphological effects less pronounced. The importance of delocalization, which has largely been ignored in past simulations, as a parameter to consider and optimize when choosing materials for organic solar cells is emphasized.

Thumbnail image of graphical abstract

The effects of charge delocalization on device efficiency is probed using mesoscale Monte Carlo simulations of charge transport in idealized and isotropic two-phase morphologies. Interfacial charge trapping is drastically reduced when Coulomb interactions are weakened through moderate delocalization (1.0–2.0 nm). Morphological differences become less dominant as charges delocalize.

16 Jan 03:29

Hexamodal Imaging with Porphyrin-Phospholipid-Coated Upconversion Nanoparticles

by James Rieffel, Feng Chen, Jeesu Kim, Guanying Chen, Wei Shao, Shuai Shao, Upendra Chitgupi, Reinier Hernandez, Stephen A. Graves, Robert J. Nickles, Paras N. Prasad, Chulhong Kim, Weibo Cai, Jonathan F. Lovell
Thumbnail image of graphical abstract

Hexamodal imaging using simple nanoparticles is demonstrated. Porphyrin-phospholipids are used to coat upconversion nanoparticles in order to generate a new biocompatible material. The nanoparticles are characterized in vitro and in vivo for imaging via fluorescence, upconversion, positron emission tomography, computed tomography, Cerenkov luminescence, and photoacoustic tomography.

09 Jul 07:14

Light-Responsive Helical Polypeptides Capable of Reducing Toxicity and Unpacking DNA: Toward Nonviral Gene Delivery

by Lichen Yin, Haoyu Tang, Kyung Hoon Kim, Nan Zheng, Ziyuan Song, Nathan P. Gabrielson, Hua Lu, Jianjun Cheng
Thumbnail image of graphical abstract

Gene delivery vehicles: Helical, cationic polypeptides with light-responsive domains showed potent membrane activity and promoted efficient cellular internalization of DNA (see picture). After transfection, a light trigger induces protecting-group removal to expose anionic carboxylate groups. The reduced cationic charge and helix distortion of the polypeptides result in enhanced DNA unpacking and reduced material toxicity because of the eliminated membrane activity.

09 Jul 03:19

Color Doppler Ultrasound and Gamma Imaging of Intratumorally Injected 500 nm Iron–Silica Nanoshells

by Alexander Liberman, Zhe Wu, Christopher V. Barback, Robert Viveros, Sarah L. Blair, Lesley G. Ellies, David R. Vera, Robert F. Mattrey, Andrew C. Kummel and William C. Trogler

TOC Graphic

ACS Nano
DOI: 10.1021/nn402507d