Publications by authors named "Keliang Gao"

Combination chemotherapeutic drugs administered via a single nanocarrier for cancer treatment provides benefits in reducing dose-limiting toxicities, improving the pharmacokinetic properties of the cargo and achieving spatial-temporal synchronization of drug exposure for maximized synergistic therapeutic effects. In an attempt to develop such a multi-drug carrier, our work focuses on functional multimodal polypeptide-based polymeric nanogels (NGs). Diblock copolymers poly (ethylene glycol)-b-poly (glutamic acid) (PEG-b-PGlu) modified with phenylalanine (Phe) were successfully synthesized and characterized.

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Tumors are inherently heterogeneous in antigen expression, and escape from immune surveillance due to antigen loss remains one of the limitations of targeted immunotherapy. Despite the clinical use of adoptive therapy with chimeric antigen receptor (CAR)-redirected T cells in lymphoblastic leukemia, treatment failure due to epitope loss occurs. Targeting multiple tumor-associated antigens (TAAs) may thus improve the outcome of CAR-T cell therapies.

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Development of an effective treatment against advanced tumors remains a major challenge for cancer immunotherapy. Approximately 50% of human melanoma is driven by B-Raf proto-oncogene mutation (BRAF mutant). Tumors with such mutation are desmoplastic, highly immunosuppressive, and often resistant to immune checkpoint therapies.

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Nanochannel electroporation (NEP) was applied to deliver precise dosages of myeloid cell leukemia-1 (Mcl-1)-specific siRNA and molecular beacons to two types of acute myeloid leukemia (AML) cells, FMS-like tyrosine kinase-3 wild-type (WT) and internal tandem duplications (ITD) type at the single-cell level. NEP, together with single-cell quantitative reverse transcription PCR, led to an observation showing nearly 20-folds more Mcl-1 siRNA than MCL1 mRNA were required to induce cell death for both cell lines and patient blasts, i.e.

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Of great interest to modern medicine and biomedical research is the ability to inject individual target cells with the desired genes or drug molecules. Some advances in cell electroporation allow for high throughput, high cell viability, or excellent dosage control, yet no platform is available for the combination of all three. In an effort to solve this problem, here we show a "3D nano-channel electroporation (NEP) chip" on a silicon platform designed to meet these three criteria.

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A micro/nano-fabrication process of a nanochannel electroporation (NEP) array and its application for precise delivery of plasmid for non-viral gene transfection is described. A dip-combing device is optimized to produce DNA nanowires across a microridge array patterned on the polydimethylsiloxane (PDMS) surface with a yield up to 95%. Molecular imprinting based on a low viscosity resin, 1,4-butanediol diacrylate (1,4-BDDA), adopted to convert the microridge-nanowire-microridge array into a microchannel-nanochannel-microchannel (MNM) array.

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Many transfection techniques can deliver biomolecules into cells, but the dose cannot be controlled precisely. Delivering well-defined amounts of materials into cells is important for various biological studies and therapeutic applications. Here, we show that nanochannel electroporation can deliver precise amounts of a variety of transfection agents into living cells.

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Although Gluconobacter oxydans can convert 1,2-propanediol to D: -(-)-lactic acid, the enzyme(s) responsible for the conversion has remain unknown. In this study, the membrane-bound alcohol dehydrogenase (ADH) of Gluconobacter oxydans DSM 2003 was purified and confirmed to be essential for the process of D: -(-)-lactic acid production by gene knockout and complementation studies. A 25 percent decrease in D: -(-)-lactic acid production was found for the aldehyde dehydrogenase (ALDH) deficient strain of G.

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Enantioselective biotransformation of DL-1,2-propanediol to D-2-hydroxypropanic acid was first reported by the authors. In the biooxidation process, there were some by-product formed and thus influenced the e.e.

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Asymmetric oxidation is of great value and a major interest in both research and application. This review focuses on asymmetric oxidation of organic compounds by Gluconobacter oxydans. The microbe can be used for bioproduction of several kinds of important chiral compounds, such as vitamin C, 6-(2-hydroxyethyl)amino-6-deoxy-alpha-L-sorbofuranose, (S)-2-methylbutanoic acid, (R)-2-hydroxy-propionic acid and 5-keto-D-gluconic acid.

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