Osteoarthritis (OA) is a musculoskeletal disorder disease affecting about 500 million people worldwide and mesenchymal sem cells (MSCs) therapy has been demonstrated as a potential strategy to treat OA. However, the shear forces during direct injection and the harsher shear condition of OA environments would lead to significant cell damage and inhibit the therapeutic efficacy. Herein, DNA supramolecular hydrogel has been applied as delivering material for MSCs to treat severe OA model, which perform extraordinary protection in MSCs against the shear force both in vitro and in vivo. It is demonstrated that the DNA supramolecular hydrogel can promote formation of quality cartilage, reduce osteophyte, and normalize subchondral bone under the high friction condition of OA, whose molecular mechanisms underlying therapeutic effects are also investigated. It can be anticipated that DNA supramolecular hydrogel would be a promising cell delivery system for multiple potential MSCs therapy.

BackgroundOur previously published reports have described an effective biocontrol agent named Pseudomonas sp. M18 as its 16S rDNA sequence and several regulator genes share homologous sequences with those of P. aeruginosa, but there are several unusual phenotypic features. This study aims to explore its strain specific genomic features and gene expression patterns at different temperatures.ResultsThe complete M18 genome is composed of a single chromosome of 6,327,754 base pairs containing 5684 open reading frames. Seven genomic islands, including two novel prophages and five specific non-phage islands were identified besides the conserved P. aeruginosa core genome. Each prophage contains a putative chitinase coding gene, and the prophage II contains a capB gene encoding a putative cold stress protein. The non-phage genomic islands contain genes responsible for pyoluteorin biosynthesis, environmental substance degradation and type I and III restriction-modification systems. Compared with other P. aeruginosa strains, the fewest number (3) of insertion sequences and the most number (3) of clustered regularly interspaced short palindromic repeats in M18 genome may contribute to the relative genome stability. Although the M18 genome is most closely related to that of P. aeruginosa strain LESB58, the strain M18 is more susceptible to several antimicrobial agents and easier to be erased in a mouse acute lung infection model than the strain LESB58. The whole M18 transcriptomic analysis indicated that 10.6% of the expressed genes are temperature-dependent, with 22 genes up-regulated at 28°C in three non-phage genomic islands and one prophage but none at 37°C.ConclusionsThe P. aeruginosa strain M18 has evolved its specific genomic structures and temperature dependent expression patterns to meet the requirement of its fitness and competitiveness under selective pressures imposed on the strain in rhizosphere niche.

• Various MRA sequences were applied for follow-up assessment of coiled intracranial aneurysms. • zTE MRA was less sensitive to susceptibility artefacts and haemodynamics. • In this monocentric study, zTE MRA was equivalent to DSA. • zTE MRA maybe an alternative to TOF MRA for follow-up assessment.

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A thermally sensitive ultralong multiblock copolymer, [poly(ethylene oxide) 23 -b-poly(N-isopropylacrylamide) 124 ] 750 (M w ) 1.78 × 10 7 g/mol and M z /M w ) 1.49), was prepared using the oxidative coupling of two mercapto groups at the two ends of triblock PNIPAM 62 -b-PEO 23 -b-PNIPAM 62 (M n,PEO ) 1.0 × 10 3 g/mol and M n,PNIPAM ) 1.4 × 10 4 g/mol) copolymer chains. The folding of individual multiblock copolymer chains in an extremely dilute solution (10 -6 g/mL) was studied by laser light scattering (LLS). Moreover, the association of multiblock and triblock copolymer chains in relatively concentrated aqueous solutions (10 -3 g/mL) was also comparatively studied by a combination of LLS, fluorescence spectrometry, and microcalorimetry. We found that in the single-chain folding process the average radius of gyration (〈R g 〉) remains a constant in one heatingand-cooling cycle, but the average hydrodynamic radius (〈R h 〉) decreases as the solution temperature increases. Our result reveals that the single-chain folding undergoes two stages at ∼32 and ∼40 °C, presumably due to the successive contraction of thermally sensitive PNIPAM segments in the middle around each hydrophobic S-S coupling point and near the hydrophilic PEO block. Each PNIPAM block collapses into a small globule (bead) stabilized by the two attached PEO blocks on the chain backbone, a string-bead conformation, which makes the chain thicker and more extended. The association of multiblock chains also undergoes similar two stages to form stable mesoglobules during the heating. In contrast, the triblock chains associate at ∼30 °C to form polymeric micelles.

Micrometer scaled nickel dendritic crystals with distinctive style were synthesized via a self-assembled solution route without any surfactant. Structure characterizations suggest that the dendritic crystal shows first preferential orientation along [111] which is the magnetic easy axis of cubic nickel crystal and subsequently along [100], which differs from the prevalent dendritic fractals synthesized in nonequilibrium system. A formation process is proposed to illustrate the growth of ferromagnetic nickel microleaves. Additionally, the magnetic properties of nickel microleaf have been observed, which demonstrates that the saturation magnetization (Ms) and the coercivity (Hc) are 48 emu/cm−3 and 77 Oe, respectively. The relatively high Ms and low Hc for as-prepared product could be attributed to its special structure.

Aging biomarkers are a combination of biological parameters to (i) assess age-related changes, (ii) track the physiological aging process, and (iii) predict the transition into a pathological status. Although a broad spectrum of aging biomarkers has been developed, their potential uses and limitations remain poorly characterized. An immediate goal of biomarkers is to help us answer the following three fundamental questions in aging research: How old are we? Why do we get old? And how can we age slower? This review aims to address this need. Here, we summarize our current knowledge of biomarkers developed for cellular, organ, and organismal levels of aging, comprising six pillars: physiological characteristics, medical imaging, histological features, cellular alterations, molecular changes, and secretory factors. To fulfill all these requisites, we propose that aging biomarkers should qualify for being specific, systemic, and clinically relevant. Supporting Information The supporting information is available online at 10.1007/s11427-023-2305-0. The supporting materials are published as submitted, without typesetting or editing. The responsibility for scientific accuracy and content remains entirely with the authors.

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