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Many technologies have been developed for breast reconstruction after lumpectomy. Although the technologies achieved promising success in clinical, there are still many shortages hanging over and trouble the researchers. Tissue engineering technology was introduced to plastic surgery that gave a light to lumpectomy patients in breast reconstruction. The unexpected absorption rate, resulting from limited vascularization and low cell survival rate, is a major factor that leads to unsatisfactory results for the previous studies in our lab. In the study, the laminin-modified alginate synthesized by a new method of low concertation of sodium periodate would be mixed with ADSCs and Rg1 in the medium; and then sprayed into a calcium chloride (CaCl2) solution to prepare into microsphere (abbreviated as ADSC–G-LAMS) by bio-electrospray with a power syringe for the mass production and smaller bead size. The developed ADSC–G-LAMS microspheres had the diameter of 232 ± 42 μm. Sustained-release of the Rg1 retained its biological activity. WST-1, live/dead staining, and chromosome aberration assay were evaluated to confirm the safety of the microspheres. In in vivo study, ADSC–G-LAMS microspheres combined with autologous adipocytes were transplanted into the dorsum of rats by subcutaneous injection. The efficacy was investigated by H&E and immunofluorescence staining. The results showed that the bioactive ADSC–G-LAMS microspheres could integrate well into the host adipose tissue with an adequate rate of angiogenesis by constantly releasing Rg1 to enhance the ADSC or adipocyte survival rate to join tissue growth and repair with adipogenesis for breast reconstruction after lumpectomy., Graphical abstract Image 1, Highlights • Laminin-modified alginate was successfully synthesized to mimic early embryonic environment. • Adipose-derived stem cells (ADSCs) and ginsenoside Rg1 were encapsulated into laminin-alginate microspheres (ADSC–G-LAMS) by bio-electrospray method. • ADSC–G-LAMS microspheres integrated into the host adipose tissue with an adequate rate of angiogenesis by constantly releasing Rg1. • The developed bioactive ADSC–G-LAMS microspheres can be potential scaffolds for stem cells and angiogenic factor carriers for tissue engineering.

Secoisolariciresinol (SECO) is a lignan of potential therapeutic value for diseases such as cancer, but its use has been limited by the lack of ideal production methods, even though its precursors are abundant in plants, such as flaxseeds. Here, we report the characterization of a bacterial strain, S1, isolated from the human intestinal flora, which could produce secoisolariciresinol by biotransformation of precursors in defatted flaxseeds. This bacterium was a Gram-negative and facultatively anaerobic straight rod without capsules. Biochemical assays showed that it was negative for production of oxidase, lysine decarboxylase, ornithine decarboxylase, arginine dihydrolase, and β-glucolase. The G + C content of genomic DNA was 57.37 mol%. Phylogenetic analysis by 16S rRNA and rpoB gene sequences demonstrated S1’s close relatedness to Klebsiella. No homologues were found for wzb or wzc (capsular genes), which may explain why Klebsiella sp. strain S1 does not have the capsule and was isolated from a healthy human individual. Based on the percentages of homologous genes with identical nucleotide sequences between the bacteria in comparison, we found that clear-cut genetic boundaries had been formed between S1 and any other Klebsiella strains compared, dividing them into distinct phylogenetic lineages. This work demonstrates that the intestinal Klebsiella, well known as important opportunistic pathogens prevalent in potentially fatal nosocomial infections, may contain lineages that are particularly beneficial to the human health.

LaCo x Fe 1− x O 3 nanoparticles ( x = 0, 0.1, 0.2, and 0.3) are prepared by a sol–gel method, and the effects of calcination temperature, Co-doping, and carbon nanotube (CNT)-treatment on their ethanol sensing properties are investigated. The highest response is found based on the LaCo 0.1 Fe 0.9 O 3 nanoparticles calcined at 600 °C, and the sensing properties of this sample can be further improved by adding CNT in the precursor. The responses of un-treated and CNT-treated LaCo 0.1 Fe 0.9 O 3 nanoparticles are about 120.1 and 137.3–500 ppm ethanol at 140 °C, respectively. Simultaneously, by CNT -treatment, the response time is decreased from 56 to 10 s, and the recovery time is decreased from 95 to 35 s. The results not only make LaCo 0.1 Fe 0.9 O 3 nanoparticles good candidates for fabricating practical gas sensors, but also provide a possible route for employing CNTs as a pore-forming agent.

In 2008, around 596 000 t of aluminum dross was generated from secondary aluminum industry in China; however, it was not sufficiently recycled yet. Approximately 95% of the Al dross was land filled without innocent treatment. The purpose of this work is to investigate Al dross recycling by environmentally efficient and friendly methods. Two methods of Al dross recycling which could utilize Al dross efficiently were presented. High-quality aluminum-silicon alloys and brown fused alumina (BFA) were produced successfully by recycling Al dross. Then, life cycle assessment (LCA) was performed to evaluate environmental impact of two methods of Al dross recycling process. The results show that the two methods are reasonable and the average recovery rate of Al dross is up to 98%. As the LCA results indicate, they have some advantages such as less natural resource consumption and pollutant emissions, which efficiently relieves the burden on the environment in electrolytic aluminum and secondary aluminum industry.

Ce-doped In2O3, nanofibers were synthesized by a simple and effective electrospinning method. The morphology and crystal structure of the as-prepared samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and scanning electron microscopy (SEM). The results revealed that the length of the nanofibers can reach several tens of micrometers and the average diameter was about 90 nm. The sensor fabricated from the 4% (w) Ce-doped In2O3 nanofibers showed the highest sensitivity to triethylamine. The sensitivity reached 2.6 when the sensor was exposed to 3μL•L^(-1) triethylamine and the response time and recovery time were about 5 and 6 s, respectively. Moreover, good selectivity was also observed in our investigation.

Due to their low cytotoxicity, controllable size, and unique architecture, cyclodextrin (CD)-based polyrotaxanes and polypseudorotaxanes have inspired interesting exploitation as novel biomaterials. This review will update the recent progress in the studies on the structures of polyrotaxanes and polypseudorotaxanes based on different CDs and polymers, followed by summarizing their potential applications in life science and biotechnology, such as drug delivery, gene delivery, and tissue engineering. CD-based biodegradable polypseudorotaxane hydrogels could be used as promising injectable drug delivery systems for sustained and controlled drug release. Polyrotaxanes with drug or ligand-conjugated CDs threaded on polymer chain with biodegradable end group could be useful for controlled and multivalent targeting delivery. Cationic polyrotaxanes consisting of multiple oligoethylenimine-grafted CDs threaded on a block copolymer chain were attractive non-viral gene carries due to the strong DNA-binding ability, low cytotoxicity, and high gene transfection efficiency. Cytocleavable end caps were also introduced in the polyrotaxane systems in order to ensure efficient endosomal escape for intracellular trafficking of DNA. Finally, hydrolyzable polyrotaxane hydrogels with cross-linked α-CDs could be a desirable scaffold for cartilage and bone tissue engineering.

Supramolecular polymers based on cyclodextrins (CDs) have inspired interesting and rapid developments as novel biomaterials in a broad range of drug and gene delivery applications, due to their low cytotoxicity, controllable size, and unique architecture. This review will summarize the potential applications of polyrotaxanes in the field of drug delivery and gene delivery. Generally, cyclodextrin-based biodegradable polypseudorotaxane hydrogels could be used as a promising injectable drug delivery system for sustained and controlled drug release. Temperature-responsive, pH-sensitive, and controllable hydrolyzable polyrotaxane hydrogels have attracted much attention because of their controllable properties, and the self-assembly micelles formed by amphiphilic copolymer threaded with CDs could be used as a carrier for controlled and sustained drug release. Polyrotaxanes with drug or ligand conjugated CDs threaded on a polymer chain with a biodegradable end group could be useful for controlled and multivalent targeted delivery. In the field of gene delivery, cationic polyrotaxanes consisting of multiple OEI-grafted CDs threaded on a block copolymer chain are attractive non-viral gene carries due to the strong DNA-binding ability, low cytotoxicity, and high gene delivery capability. Furthermore, cytocleavable end-caps were introduced in the polyrotaxane systems in order to ensure efficient endosomal escape for intracellular trafficking of DNA. The development of the supramolecular approach using CD-containing polyrotaxanes is expected to provide a new paradigm for biomaterials.

Inclusion complexes (ICs) composed of α-cyclodextrins (α-CD) and biodegradable comblike copolymers with poly(α,β-malic acid) (PMA) backbones and methylated poly(ethylene glycol) (mPEG) side chains were prepared by the host-guest reaction. Two series of ICs with mPEG750 and mPEG2000 were prepared. The stoichiometry (EG/CD) of all the ICs in mPEG2000 series was 3.1, no matter what the graft degree was. While in mPEG750 series, the stoichiometry (EG/CD) was very different; it increased with the amount of mPEG decreasing. The decomposition temperatures of the fragments in ICs were closely related to graft degrees. The stack of α-CDs in ICs was a channel-type structure. The crystal of ICs was lamellar, and it could be reorganized to well-defined supermolecular structure.