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关键词： nerve regeneration   stem cell   nerve growth factor   rotary cell culture system   in vivo  

摘要： Peripheral nerve injury (PNI) was the leading cause of permanent dysfunction in movement and sensation. Synthesized nerve guide conduits (NGCs) with Schwann Cells (SCs) can help peripheral nerve regeneration. However, poor accessibility of SCs and lack of full coverage of seeded cells on NGCs can lead to failure of nerve regeneration across long gaps and full functional recovery. To overcome these limitations, bone marrow stromal cells (BMSCs) and a novel culture method were proposed in the current study. BMSCs were harvested and seeded on a never growth factor (NGF)-loaded PCL nanofibrous NGCs and cultured with a rotary cell culture system (RCCS) before implantation. The NGCs were tested in vitro with PC-12 cells to validate the bioactivity of released NGF and to access its ability to promote neurite extension. Also, the NGCs were tested in vivo with rat sciatic nerve model to exam its potential in bridging the long gap (15 mm segmental defect). The efficacy of the NGCs was investigated based on the results of the functional test, electrophysiology test, muscle atrophy, and histological analysis. The results of in vitro PC-12 cell study confirmed the bioactivity of released NGF and showed a significant increase in the neurite extension with the help of PEG-diamine and BSA. These results showed that the novel loading method could preserve the bioactivity of growth factors and achieve a sustained release in vitro. Besides, the results of the in vivo study exhibited a significant increase with the combination of all additives. These results showed that with the help of NGF and RCCS, the NGCs with the seeded BMSCs could enhance peripheral nerve regeneration across long nerve injury gaps.

关键词： Glucose oxidase  

摘要： The development of highly effective and minimally invasive approaches for cancer treatment is the ultimate goal. Herein, an injectable hybrid hydrogel as a biomimetic cascade bioreactor is designed for combination antitumor therapy by providing spatiotemporally-controlled and long-term delivery of therapeutic agents. This hybrid nanozyme@hydrogel (hPB@gellan) is doped with Prussian blue (PB) nanoparticles via the in situ nanoprecipitation method in the polysaccharide gellan matrix. The obtained PB nanoparticles have a small size of 10 nm and play dual roles as a photothermal agent with a photothermal conversion efficiency of 59.6% and as a nanozyme to decompose hydrogen peroxide into oxygen. By incorporating glucose oxidase (GOD) into the hybrid hydrogel, a cascade bioreactor is formed for PB-promoted glucose consumption. Owing to its shear-thinning and self-recovery properties, the hybrid hydrogel is locally administered into tumors, and shows long-term resistance against body clearance and metabolism. The in vivo antitumor results demonstrate that the tumors in the group of combined photothermal and starvation therapy (GOD/hPB@gellan + NIR) are greatly eliminated with a tumor suppression rate of 99.7% 22 days after the treatment. The outstanding antitumor performance is attributed to the main attack by NIR-triggered hyperthermia and the holding attack by GOD-mediated starvation from the catalytic bioreactor of the hybrid hydrogel. Taking into consideration the advantages of biosafety, simple synthetic approaches and facile manipulation in treatment, the hybrid hydrogel has great potential for clinical translation.

关键词： Fermentation   X-ray absorption near edge spectroscopy   Iron   Biotechnology   Sludges  

摘要： The transformation of Fe-P complexes in bioreactors can be important for phosphorus (P) recovery from sludge. In this research, X-ray absorption near-edge structure analysis was conducted to quantify the transformation of Fe and P species in the sludge of different aging periods and in the subsequent acidogenic cofermentation for P recovery. P was readily removed from wastewater by Fe-facilitated coprecipitation and adsorption and could be extracted and recovered from sludge via acidogenic cofermentation and microbial iron reduction with food waste. The fresh Fe-based sludge mainly contained fresh ferrihydrite and amorphous FePO4 with sufficient accessible surface area, which was favorable for Fe-P mobilization and dissolution via microbial reaction. Ferric iron dosed into wastewater underwent rapid hydrolysis, clustering, aggregation, and slow crystallization to form hydrous iron oxides (HFO) with various complicated structures. With the aging of sludge in bioreactors, the HFO densified into phases with much reduced surface area and reactivity (e.g., goethite), which greatly increased the difficulty of P release and recovery. Thus, aging of P-containing sludge should be minimized in wastewater treatment systems for the purpose of P recovery.

关键词： Bioreactor   CYP1A2   Magnetic nanoparticles  

摘要： A new 96-well plate methodology for fast, enzyme-multiplexed screening for metabolite-protein adducts was developed. Magnetic beads coated with metabolic enzymes were used to make potentially reactive metabolites that can react with test protein in the wells, followed by sample workup in multiple 96-well filter plates for LC-MS/MS analysis. Incorporation of human microsomes from multiple organs and selected supersomes of single rytochrome P450 (cyt P450) enzymes on the magnetic beads provided a broad spectrum of metabolic enzymes. The reacted protein was then isolated, denatured, reduced, allcylated, and digested, and peptides were collected in a sequence of 96-well filter plates for analysis. Method performance was evaluated by trapping acetaminophen reactive metabolite N-acetyl-p-benzoquinoneimine (NAPQI) with human glutathione S-transferase pi (hGSTP), human serum albumin (HSA), and bovine serum albumin (BSA) as model target proteins. Relative amounts of acetaminophen metabolite and hGSTP adducts were compared with 10 different cyt P450 enzymes. Human liver microsomes and CYP1A2 supersomes showed the highest bioactivation rate for adduct formation, in which all four cysteines of hGSTP reacted with NAPQI. Eight cysteines of HSA and four cysteines of BSA have been detected to react with NAPQI. This method has the potential for fast multienzyme protein adduct screening with high efficiency and accuracy.

关键词： bioreactor   three-dimensional   tissue culture   stem cells   liver slices  

摘要： As the field of tissue engineering continues to advance rapidly, so too does the complexity of cell culture techniques used to generate in vitro tissue constructs, with the overall aim of mimicking the in vivo microenvironment. This complexity typically comes at a cost with regards to the size of the equipment required and associated expenses. We have developed a small, low-cost bioreactor system which overcomes some of the issues of typical bioreactor systems while retaining a suitable scale for the formation of complex tissues. Herein, we have tested this system with three cell populations/tissues: the culture of hepatocellular carcinoma cells, where an improved structure and basic metabolic function is seen;the culture of human pluripotent stem cells, in which the cultures can form more heterogeneous tissues resembling the in vivo teratoma and ex vivo liver tissue slices, in which improved maintenance of cellular viability is seen over the 3 days tested. This system has the flexibility to be used for a variety of further uses and has the potential to provide a more accessible alternative to current bioreactor technologies.

关键词： Bioreactor   Clonal fidelity   Chlorophylls   Micropropagation   Molecular markers   Shoot regeneration  

摘要： Efficient systems to multiply adventitious shoots regenerated from excised leaves of greenhouse-grown wild Vaccinium vitis-idaea L. ssp. minus (Lodd.) Hult. (lingonberry) clones were developed in vitro. Shoot regeneration took place when the leaf explants were cultured on a semi-solid gelled medium, positioned with the adaxial or abaxial side touching the culture medium and maintained in darkness for 2 weeks followed by culturing for another 6 weeks under light. Although zeatin (9.1 mu M) or TDZ (1.8 mu M) were efficient to induce adventitious shoots from leaf explants, shoot elongation was better on a medium with zeatin. Nodal segments of regenerated shoots were evaluated for shoot proliferation on a semi-solid and in a liquid medium using stationary (SB) and temporary immersion bioreactors (TIB). After 8 weeks of culture, shoot multiplication was 2-3 times more in liquid medium than on a semi-solid medium. Although shoots proliferated in a liquid medium containing 9.1 mu M zeatin or 1.8 mu M TDZ showed 10 % and 25 hyperhydricity in SB and TIB respectively, rooting was not affected when regenerated shoots were dipped into 39.4 mM indole-3-butyric acid powder and planted in a 2:1 of peat: perlite medium. Liquid culture-derived plants when transferred to a greenhouse for acclimatization, 90-95 % plants survived. Micropropagated plants were phenotypically similar to the donor mother plants although the contents of chlorophyll a and b were more in the leaves of cutting propagated plants compared to micropropagated ones. Expressed sequence tag - simple sequence repeat (EST-SSR), EST- polymerase chain reaction (PCR) and inter simple sequence repeat (ISSR) banding profiles of the regenerated plants were monomorphic like those of the donor plants that confirmed clonal fidelity of tissue culture plants derived from in vitro leaf culture in V. vitis-idaea ssp. minus.

摘要： The article "Development of an efficient bioreactor system for delivering foreign proteins secreted from liver into eggs with a vitellogenin signal in medaka Oryzias latipes", written by Yu Murakami, Tomohisa Horibe and Masato Kinoshita was originally published electronically on the publisher's internet portal on 21 May 2019 without open access. After publication in volume [85], issue [4], page [677-685] with the author(s)' decision to opt for Open Choice the copyright of the article changed on 31st March 2020 to The Author(s) 2020 and the article is forthwith distributed under a Creative Commons Attribution 4.0 International License

关键词： Bioreactor   coffee fermentation   coffee beverage   Pichia fermentans   starter culture  

摘要： Coffee growers use a traditional method of fermentation to remove the cherry pulp surrounding the beans. The aim of this study was to evaluate the microbiological, physicochemical, and sensory aspects of coffee beans fermentation conducted in a controlled yeast bioreactor model (New Brunswick (TM) BioFlo (R)). Fermentations were conducted with or without the addition of a selected yeast starter culture (viz., Pichia fermentans YC5.2) and different parameters, including microbial growth, bacterial diversity, inoculum persistence, sugar consumption, and metabolic compounds formation (organic acids, ethanol, and ethyl acetate), were investigated. The chemical composition of resulting fermented coffee beans was assessed by high-performance liquid chromatography and gas chromatography-mass spectrometry, and sensorial analysis of coffee beverage was performed using the cupping test (SCA - specialty coffee association). The yeast bioreactor model enabled efficient yeast starter culture growth and ethanol (0.136 g/L.h) and ethyl acetate (1.039 mg/L.h) formation. The bacterial population was mainly represented by Pediococcus sp. and Leuconostocaceae family, as revealed by Illumina high-throughput 16S rRNA gene sequencing. The fermentation system also enabled the production of coffee beans with rich aroma composition (including D-Limonene, phenyl-acetaldehyde, and phenylethyl alcohol) and beverages with a remarkable increase in quality compared to the conventional process. With further refinements, the stirred-tank bioreactor (STR) model may be useful in designing novel bioreactors for the optimization of coffee fermentation with starter cultures.

关键词： 微藻   规模培养   光生物反应器  

摘要： 微藻具有固定CO2和净化有机废水的能力,在环保、食品饲(饵)料、医药和生物能源开发等领域备受关注,但规模化培养及其产业化仍是研究的难点,亟待解决。就常用于大规模培养微藻的光生物反应器的特点和结构进行了综述。其中,封闭式微藻光生物反应器能够较好地调控藻种的培养条件、不易遭受污染,藻种的纯度容易控制,但培养规模小,生产成本较高;而开放式微藻光生物反应器无法精确控制藻种生长环境,但生产规模大、产量高、生产成本低,因此应用广泛。最佳的方法是综合两者优点,即首先利用封闭式微藻光生物反应器进行中试放大,大量繁殖藻种,然后投入开放式微藻光生物反应器内进行大规模商业生产,此方法有望成为微藻光生物反应器的发展方向,以期为微藻大规模培养提供参考借鉴。

关键词： 正渗透   厌氧膜生物反应器   高COD废水   溶解性甲烷  

摘要： 研究厌氧正渗透膜生物反应器(AnOMBR)处理高COD(3~9 g/L)有机废水的除污染效能和产能情况。结果表明,正渗透膜初始水通量为6 L/(m^2·h),运行10 d后,物理清洗和化学清洗结合,膜通量恢复95%。反应器内电导率和pH均增加,挥发性脂肪酸的含量较低,AnOMBR对COD的去除效率高达93%以上。当进水COD为6 g/L时,最高甲烷产量为0.256 L/g。原料液侧的溶解性甲烷的含量随着进水COD的增加而降低,质量浓度基本稳定为7 mg/L。