RESUMEN
Inspired by the imbalance between extrinsic and intrinsic tendon healing, this study fabricated a new biofilter scaffold with a hierarchical structure based on a melt electrowriting technique. The outer multilayered fibrous structure with connected porous characteristics provides a novel passageway for vascularization and isolates the penetration of scar fibers, which can be referred to as a biofilter process. In vitro experiments found that the porous architecture in the outer layer can effectively prevent cell infiltration, whereas the aligned fibers in the inner layer can promote cell recruitment and growth, as well as the expression of tendon-associated proteins in a simulated friction condition. It was shown in vivo that the biofilter process could promote tendon healing and reduce scar invasion. Herein, this novel strategy indicates great potential to design new biomaterials for balancing extrinsic and intrinsic healing and realizing scarless tendon healing.
RESUMEN
The affinity interactions between boronic acids and sugars have been successfully exploited in many fields, such as the sensing of saccharides, selective enrichment of glycoconjugates, and drug delivery. However, despite multiple techniques having been adopted to investigate the reaction of boronate affinity, the pathway of boronate esters formation under aqueous conditions remains controversial. We report a MALDI-MS approach to investigate the interactions between phenylboronic acid and monosaccharides in neutral aqueous solution by using polylevodopa as an innovative substrate instead of conventional matrix. A series of unusual tri-benzeneboronic esters were then revealed. The mass spectrometry data indicate that they bear a dibenzenepyroboronate cyclic ester moiety with seven-membered ring or eight-membered ring. With the aid of theoretical computations, their most likely geometrical structures are elucidated, and these tri-benzeneboronic esters are proposed to be formed via a boroxine binding monosaccharide pathway. This work provides more insight into the mechanism of boronate affinity interaction between boronic acid and sugars and proves the developed MALDI-MS approach is promising for studying interactions between small molecules.
RESUMEN
Purpose: Surgery-induced immunosuppression is associated with infectious complications and cancer recurrence. This study aimed to characterize the effects of perioperative multiple doses of glucocorticoids on the peripheral immune environment in patients with non-small cell lung cancer. Methods: In this retrospective study, surgical patients with lung cancer were included. Lymphocyte subsets, lymphocyte phenotypes, lymphocyte functions, and inflammatory cytokines were evaluated in the peripheral blood preoperatively, then at 1 day and 7 days postoperatively. Levels of immune cells and inflammatory factors were compared between those who did or did not receive glucocorticoids at all time points. Results: Multiple doses or high doses (15-20 mg dexamethasone equivalents) of glucocorticoids that were all given within 24 h were associated with decreased absolute numbers of T cells, CD4+and CD8+T cells, B cells, and impaired T cells function at 1 day postoperatively while a single intraoperative low dose (5 mg) of dexamethasone had little influence on the peripheral environment. IL-1ß, IL-6, and TNF-α were also more affected by multiple doses of glucocorticoids. Conclusions: Among patients with lung cancer, perioperative multiple doses of glucocorticoids that are all given within a short time are associated with decreased immune cell counts and impaired T cells functions.
RESUMEN
Solid-liquid lubricating systems have received significant attention as a promising way for energy saving and emission control. For deeply understanding their tribological behaviors, it is necessary to study interaction mechanisms between solid and liquid lubricants from the tribochemical viewpoint, as tribofilms formed by tribochemical products on contact surfaces critically affect the whole tribological process. Continually or periodically monitoring tribofilm formation and evolution can contribute significantly to clarifying its dominating role in tribological behavior under boundary lubrication. However, detecting tribofilms in situ remains a big challenge for conventional surface analytical approaches, mainly due to their limitations in accessing tribofilms or low signal intensities of thin tribofilms. In this study, highly sensitive Raman-based profilometry with in situ potential has been developed for detecting molybdenum dialkyldithiocarbamate (MoDTC)-derived tribofilms and exploring their effect on a-C:H wear over time. The optical properties of tribochemical products formed on the coating surface in different wear stages could result in extra attenuation of Raman signal intensities in the form of measurement deviations in wear depth. By monitoring the deviations, key information of tribofilm compositions was obtained and a two-stage wear progression mechanism was proposed for the first time to clarify the detrimental effect of MoDTC-derived tribofilms on a-C:H wear by combining detailed structure and composition analyses.
