The application of PEG-b-PCL micelles was dampened by their inherent low drug-loading capability and relatively poor cell uptake efficiency. In this study, a series of novel PEG-b-PCL copolymers methoxy poly(ethylene glycol)-b-poly(ε-caprolactone-co-γ-dimethyl maleamidic acid -ε-caprolactone) (mPEG-b-P(CL-co-DCL)) bearing different amounts of acid-labile β-carboxylic amides on the polyester moiety were synthesized. The chain structure and chemical composition of copolymers were characterized by (1)H NMR, Fourier transform infrared spectroscopy (FT-IR), and gel permeation chromatography (GPC). mPEG-b-P(CL-co-DCL) with critical micellar concentrations (CMCs) of 3.2-6.3 μg/mL could self-assemble into stable micelles in water with diameters of 100 to 150 nm. Doxorubicin (DOX), a cationic hydrophobic drug, was successfully encapsulated into the polymer micelles, achieving a very high loading content due to electrostatic interaction. Then the stability, charge-conversional behavior, loading and release profiles, cellular uptake and in vitro cytotoxicity of free drug and drug-loaded micelles were evaluated. The β-carboxylic amides functionalized polymer micelles are negatively charged and stable in neutral solution but quickly become positively charged at pH 6.0, due to the hydrolysis of β-carboxylic amides in acidic conditions. The pH-triggered negative-to-positive charge reversal not only resulted in a very fast drug release in acidic conditions, but also effectively enhanced the cellular uptake by electrostatic absorptive endocytosis. The MTT assay demonstrated that mPEG-b-P(CL-co-DCL) micelles were biocompatible to HepG2 cells while DOX-loaded micelles showed significant cytotoxicity. In sum, the introduction of acid-labile β-carboxylic amides on the polyester block in mPEG-b-P(CL-co-DCL) exhibited great potentials for the modifications in the stability in blood circulation, drug solubilization, and release properties, as well as cell internalization and intracellular drug release.

Learning continuous representations of nodes is attracting growing interest in both academia and industry recently, due to their simplicity and effectiveness in a variety of applications. Most of existing node embedding algorithms and systems are capable of processing networks with hundreds of thousands or a few millions of nodes. However, how to scale them to networks that have tens of millions or even hundreds of millions of nodes remains a challenging problem. In this paper, we propose GraphVite, a high-performance CPU-GPU hybrid system for training node embeddings, by co-optimizing the algorithm and the system. On the CPU end, augmented edge samples are parallelly generated by random walks in an online fashion on the network, and serve as the training data. On the GPU end, a novel parallel negative sampling is proposed to leverage multiple GPUs to train node embeddings simultaneously, without much data transfer and synchronization. Moreover, an efficient collaboration strategy is proposed to further reduce the synchronization cost between CPUs and GPUs. Experiments on multiple real-world networks show that GraphVite is super efficient. It takes only about one minute for a network with 1 million nodes and 5 million edges on a single machine with 4 GPUs, and takes around 20 hours for a network with 66 million nodes and 1.8 billion edges. Compared to the current fastest system, GraphVite is about 50 times faster without any sacrifice on performance.

Molecularly imprinted polymers (MIPs) are chemically synthesized affinity materials with tailor‐made binding cavities complementary to the template molecules in shape, size, and functionality. Recently, engineering MIP‐based nanomedicines to improve cancer therapy has become a rapidly growing field and future research direction. Because of the unique properties and functions of MIPs, MIP‐based nanoparticles (nanoMIPs) are not only alternatives to current nanomaterials for cancer therapy, but also hold the potential to fill gaps associated with biological ligand‐based nanomedicines, such as immunogenicity, stability, applicability, and economic viability. Here, we survey recent advances in the design and fabrication of nanoMIPs for cancer therapy and highlight their distinct features. In addition, how to use these features to achieve desired performance, including extended circulation, active targeting, controlled drug release and anti‐tumor efficacy, is discussed and summarized. We expect that this minireview will inspire more advanced studies in MIP‐based nanomedicines for cancer therapy.

Prodrug and drug delivery systems are two effective strategies for improving the selectivity of chemotherapeutics. Molecularly imprinted polymers (MIPs) have emerged as promising carriers in targeted drug delivery for cancer treatment, but they have not yet been integrated with the prodrug strategy. Reported here is an MIP‐based smart prodrug delivery system for specific targeting, prolonged retention time, and tumor microenvironment‐triggered release. 5′‐Deoxy‐5‐fluorocytidine (DFCR) and sialic acid (SA) were used as a prodrug and a marker for tumor targeting, respectively. Their co‐imprinted nanoparticles were prepared as a smart carrier. Prodrug‐loaded MIP specifically and sustainably accumulated at the tumor site and then gradually released. Unlike conventional prodrug designs, which often require in‐liver bioconversion, this MIP‐based prodrug delivery is liver‐independent but tumor‐dependent. Thus, this study opens new access to the development of smart prodrug delivery nanoplatforms.

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With increasingly rigorous requirements for biomaterials, the design and fabrication of novel materials with smart functions are urgently needed. The fabrication of composite materials that can surmount individual shortcomings as well as bring synergistic benefits represents an efficient route to improve the performances and expand application scopes of biomaterials. Due to their unique structures and properties, electrospun-fibers and hydrogels have been widely applied in many biological and biomedical fields. Based on this, more and more attentions have been paid on the composites of electrospun-fibers and hydrogels as biomaterials, aiming to bring their individual superiority into full play as well as remedy their intrinsic defects. This review summarizes approaches used to integrate electrospun-fibers and hydrogels into various structures and the development of their composites as a potential solution to some current challenges in drug delivery, tissue engineering and some other bio-related aspects. The individual roles and mutual synergy of electrospun-fibers and hydrogels in the composites will be emphasized.

Combination delivery systems composed of injectable hydrogels and drug-incorporated micelles or nanoparticles with tunable and convenient properties for clinical operation and storage are urgently demanded in regional cancer chemotherapy to prolong and control drug release, enhance antitumor efficiency and decrease side effects. Previously, we developed a novel thermosensitive amphiphilic triblock copolymer, poly (3-caprolactone-co-1,4,8-trioxa[4.6]spiro-9-undecanone)-poly(ethylene glycol)poly (3-caprolactone-co-1,4,8-trioxa[4.6]spiro-9-undecanone) (PECT), and fabricated a reconstituted "two into one" combination system of thermosensitive injectable hydrogel PTX/PECT Gel , assembled from paclitaxel (PTX)-loaded PECT nanoparticles (NPs). PTX/PECT Gel could be stored as freeze-dried powders of paclitaxel-loaded PECT NPs, which could be reconstituted into aqueous fluid dispersions at ambient temperature just by mixing with water after gentle stirring for several minutes, and form a hydrogel at the injected site in vivo. Herein, the drug release, in vivo morphology, antitumor efficiency and pharmacokinetic properties of PTX/PECT Gel were evaluated. The PTX/PECT Gel combination system could continuously release PTX in a near linear manner over 42 days in vitro, and simultaneously, PTX/PECT NPs containing 75% of the total released PTX could dissociate from the PTX/PECT Gel . PTX/PECT Gel exhibited remarkable in vitro anti-proliferative activities against Ehrlich ascites carcinoma (EAC) cancer cells. The peritumorally or intratumorally injected PECT gel could cover the entire surface or fill up the interior space of the tumor, respectively. A single peritumoral injection of the PTX/PECT Gel formulation at a low dosage of 10 mg kg À1 could completely inhibit the growth of an EAC tumor inoculated in Balb/c mice after the first week, and the inhibition could be sustained for more than 21 days. The plasma pharmacokinetic study demonstrated that PTX/PECT Gel could greatly decrease the systemic exposure of PTX, as confirmed by the rather low plasma concentration. On the other hand, the PTX concentration in normal tissues with the intratumoral injection of PTX/PECT Gel was approximately 2 mg g À1 , which was 3-10 times lower than that with the intraperitoneal or intratumoral injection of TaxolÒ, implying fewer off-target side effects. These data confirmed that the PTX/PECT Gel combination local delivery system could vastly prolong the in vitro and in vivo paclitaxel release, enhance the local tumor inhibition effect and lower the systemic exposure and tissue distribution of paclitaxel. Hence, the "two into one" PTX/PECT Gel system holds underlying value for regional cancer chemotherapy.

Accurate analyzing particular glycosylation status of protein biomarkers is of significant importance in precise early diagnosis of cancer. Existing methods mainly rely on the use of antibodies and lectins. However,...