No abstract

After peripheral nerve injury, Wallerian degeneration (WD) occurs in the distal nerve segment. During the process of degeneration, Schwann cells (SCs) dedifferentiate, proliferate and migrate to align in “bands of Büngner”, providing structural guidance and growth-promoting substrates to regenerating axons. The molecular signals that trigger SCs migration remain unclear. Here, we explored the molecular characteristics of the migration of cultured SCs prepared from rat sciatic nerves that had degenerated. The results revealed that elevated p-ERK1/2 was coupled with the migration of SCs, activated either by nerve degeneration or the addition of placenta growth factor. However, the inhibition of ERK1/2 activity, which activated the PI3K pathway, did not show a significant negative effect on SC migratory potential. Combined inhibition of ERK1/2 and AKT activity resulted in a significant decrease in SCs motility. These molecular characteristics suggest that both the ERK1/2 and AKT signals are involved in the migratory potential of SCs. It may be helpful to understand the process of nerve regeneration and perspective on promoting peripheral nerve regeneration.

Privacy-preserving publishing of graph data, such as social networks, has been gaining much public attention in recent years due to the growing demands for publishing graph data containing privacy information. Most of the existing approaches for graph anonymization deal with unlabeled graphs, while labeled graphs have useful real-life applications. However, it is proven that k-anonymity problem edgelabeled graphs is computationally expensive. In this paper, we devise a greedy heuristic based approach for k-anonimity problem over edge-labeled graphs. More precisely, we deal with some utility metrics to achieve better anonymization results. To show the effectiveness of the proposed schemes, we conduct a set of experimental evaluations using synthetic and real datasets. The results reveal that our proposed scheme can successfully anonymize edge-labeled graphs. We also assess how the utility of the anonymized graphs is affected by the proposed algorithms.

Rationale Compared with traditional labelling reagents used in proteomics, maleic anhydride is milder and can be easily removed under certain conditions, thus simplifying chemical derivatization. Methods The proposed strategy combined a site‐specific chemical labelling reaction with mass spectrometry. Site‐selective, reversible N‐terminal maleylation was controlled by pH. Results Selective maleyl N‐terminal labelling was achieved with high efficiency under the optimized reaction conditions. The demaleylation conditions were also optimized. The sequence coverage of histone H4 increased from 77% to 95% after the maleyl labels were removed, and the number of maleylated peptides was five times that of the unlabelled peptides. We further verified the reversible and selective N‐terminal labelling properties of maleic anhydride through propionylation labelling at the peptide/protein level. Conclusions A new method for site‐selective maleylation of the N‐terminal amino groups of a peptide was explored. Through the optimization experiment, good efficiency was achieved for this labelling reaction. The reversibility of maleylation labelling was also explored and applied for the identification of post‐translational modifications of histones. Thus, site‐selective, reversible, pH‐induced N‐terminal labelling using maleic anhydride has greater potential for application in proteomics than any other labelling methods.

Symphalangism is a rare genetic condition characterized by ankylosis of the proximal interphalangeal (PIP) or/and distal interphalangeal (DIP) joints. The patient presented with fused bilateral PIP joints and poor flexion, and an unsatisfactory range of motion (ROM) in the metacarpophalangeal (MP) and DIP joints. Concomitantly, multi-carpal coalition, proximal carpal malalignment, and ulnar styloid process abnormality were also observed in radiographs obtained at diagnosis. Rehabilitation training of the MP and DIP joints and a wrist supporter were recommended to achieve MP and DIP functional motion and restrict dramatic wrist motion. This is the first case report of symphalangism with multi-carpal coalition and abnormality of the ulnar styloid process to the best of our knowledge.