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Komagataella phaffii is an important cell factory for recombinant protein production under methanol induction. Tracking of recombinant protein expression by single K. phaffii cell is a hot topic to identify the variation of expression level in submerge cultivation system. In this study, a platform system harnessing Aspergillus niger pellets for K. phaffii cell immobilization in fabricated glass plate was developed to measure the green fluorescent protein (GFP) expression of single cell using fluorescence microscope. This system was optimized through pellets preparation, K. phaffii cell absorption, inducer comparison, methanol concentration, flow velocity of medium, and obtaining a successful platform to track GFP expression of single K. phaffii cell. This system provided an on-line analytical technology to discover the heterogeneous capability of various K. phaffii cells.

As a good fluorescent material, most I–III–VI ternary semiconductor quantum dots (QDs) do not contain heavy metal elements such as Cd and Pb and thus have low toxicity. In addition, they also have excellent data performance such as narrow band gap, large absorption coefficient, large Stokes shift, low self-absorption effect, and luminescence wavelength in the near infrared region. I–III–VI QDs also have a size-dependent luminescence in the visible and near-infrared ranges, and their fluorescence quantum yields can exceed 50% especially when coated with ZnS shells, thus offering great potential for applications in illumination, display, and bioimaging. The review focuses on the synthesis of group I–III–VI QDs, their properties, and applications. In the first part, we discuss the approaches to synthesize these QDs. In the second section, we provide an overview of the applications of I–III–VI QDs in food safety detection, with emphasis on the detection of heavy metal ions, foodborne pathogens, food additives, pesticide, and veterinary drug residues. The final section summarizes the current application prospects of ternary semiconductor QDs.

Nanomaterials with unique nanotube arrays have attracted extensive attention in the field of blood-contacting biomaterials. In this study, the regular titanium dioxide nanotube arrays were first prepared on the pure titanium surface by anodic oxidation. Subsequently, copper ions (Cu2+) and strontium ions (Sr2+) were incorporated into the nanotubes by the chelation of dopamine to improve biocompatibility. The as-prepared TiO2 nanotubes had an inner diameter of about 60 nm and an outer diameter of 90–110 nm, as well as a tube length of 4–6 µm. The following annealing treatment and the incorporation of Cu2+ and Sr2+ had little effect on the morphology and dimensions of the nanotubes, but can significantly improve the hydrophilicity, and promote the adsorption of bovine serum albumin concurrently inhibit the adsorption of fibrinogen, showing the effect of selective protein adsorption. At the same time, loading Cu2+ and Sr2+ can also effectively inhibit platelet adhesion and activation, promote endothelial cell growth, and upregulate the expression of vascular endothelial growth factor and nitric oxide. Therefore, the results of this study showed that the incorporation of Cu2+ and Sr2+ into the TiO2 nanotubes can simultaneously improve the hemocompatibility and cytocompatibility of endothelial cells, which can enlarge the application of titanium-based biomaterials in cardiovascular devices such as a stent.

Food safety and quality have gained much attention and the capability to evaluate food quality and safety in a sensitive, rapid, and reliable manner is of great importance in the food industry. Surface-enhanced Raman scattering (SERS) with the advantages of excellent sensitivity, high selectivity, non-destructive nature, and significant enhancement to identify the target has demonstrated a great potential for quick detection of the food sample. The enhancement of Raman signals for SERS is not only related to the interactions between substrates and samples but also the functionalization of substrates to gain SERS active substrates. In the present review, this paper summarized the progress of SERS quantitative analysis and application in food safety detection. The future trends and perspectives were also given.

S-adenosylmethionine (SAM) is an important compound in living organisms and has a number of different roles, such as polyamine synthesis. It can also be used for the treatment of diseases. Gene targeting with homologous recombination in Komagataella phaffii (K. phaffii) created DAS1 and DAS2 gene knockout strains, which use the methanol pathway to generate more ATP and increase SAM production. These strains showed an increase in the flux of methanol oxidation and an increase in ATP production. The gene knockout retarded the cell growth in the late phase of induction, did not influence the total methanol consumption or the activity of SAM synthetase, but did significantly increase the yield of SAM by 43.7%. The metabolic flux of methanol oxidation is increased by DAS1 and DAS2 gene knockout, which leads to an increase in ATP and higher SAM production. [ABSTRACT FROM AUTHOR]

An unprecedented Pd-catalyzed cascade alkyne insertion/Heck/C-H activation reaction of o -iodophenyl alkenyl ethers and diarylacetylenes has been developed. Diversified tetracyclic-fused dihydroindeno[2,1- b ]chromenes bearing a quaternary center were constructed in an efficient, straightforward, and atom-economic way with good to excellent yields. The protocol features high bonding efficiency, operational simplicity, broad substrate scope, and easy scale-up.

Zinc ions (Zn 2+ ) are a highly potent bioactive factor with a broad spectrum of physiological functions. In situ continuous and controllable release of Zn 2+ from the biomaterials can effectively improve the biocompatibility and antibacterial activity. In the present study, inspired by the adhesion and protein cross-linking in the mussel byssus, with the aim of improving the biocompatibility of titanium, a cost-effective one-step metal-catecholamine assembly strategy was developed to prepare a biomimetic dopamine-Zn 2+ (DA-Zn 2+ ) coating by immersing the titanium oxide nanotube (TNT) arrays on the titanium surface prepared by anodic oxidation into an aqueous solution containing dopamine (DA) and zinc ions (Zn 2+ ). The DA-Zn 2+ coatings with the different zinc contents exhibited excellent hydrophilicity. Due to the continuous release of zinc ions from the DA-Zn 2+ coating, the coated titanium oxide nanotubes displayed excellent hemocompatibility characterized by platelet adhesion and activation and hemolysis assay. Moreover, the DA-Zn 2+ -coated samples exhibited an excellent ability to enhance endothelial cell (EC) adhesion and proliferation. In addition, the DA-Zn 2+ coating can also enhance the antibacterial activity of the nanotubes. Therefore, long-term in situ Zn 2+ -releasing coating of the present study could serve as the bio-surfaces for long-term prevention of thrombosis, improvement of cytocompatibility to endothelial cells, and antibacterial activity. Due to the easy operation and strong binding ability of the polydopamine on various complicated shapes, the method of the present study can be further applied to other blood contact biomaterials or implantable medical devices to improve the biocompatibility., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Hu, Zhou, Liu, Yang, Zhang, Pan and Lin.)

Objective: This study aimed to investigate the correlation between coronary artery stenosis and Mimecan expression in patients with coronary heart disease (CHD)., Methods: Seventy eight patients with CHD and 80 controls without vascular lesions were recruited into present study. CHD patients were divided into one-vessel CHD subgroup, 2-vessel CHD subgroup and multivessel CHD subgroup. ELISA was performed to detect the expressions of serum Mimecan and nuclear factor kappaB (NF-κB)., Results: When compared with control group, the expressions of serum mimecan gene and NF-κB significantly increased in CHD groups (P < 0.05); When compared with one-vessel and two-vessel CHD subgroups, the expressions of serum mimecan and NF-κB significantly increased in multivessel CHD subgroup (P < 0.05), significant difference was observed among three subgroups (P < 0.05). The expressions of serum mimecan and NF-κB were positively related to the severity of coronary lesions (rmimecan=0.79, rNF-κB=0.83, P < 0.05)., Conclusion: Increased expressions of serum mimecan and NF-κB in CHD patients are related to cardiac insufficiency, which may be ascribed to the binding of NF-κB to mimecan gene.