ANXA1 affects murine hair follicle growth through EGF signaling pathway.

Annexin A1 (ANXA1), a calcium-dependent phospholipid binding protein expressed in animals, plants and microorganisms, participates in various cellular physiological activities. Previous proteomics analysis indicates that the level of ANXA1 in mice dorsal skin changes during hair growth cycle, we speculate that ANXA1 may play an important role in hair follicle (HF) development. Thus, Anxa1 knock-out (KO) and over-expression (OE) mice were constructed to test its function. Our results showed that in addition to the diameter of HF and hair shaft, ANXA1 could participate in hair growth by affecting the density of HF, and the proliferation of hair follicle stem cells (HFSCs). Meanwhile, molecular analysis showed that EGF signaling pathway is involved in the function of ANXA1. The expression of Anxa1 is negatively correlated with the levels of Egf, Notch1, Mkk7, and phosphorylated AKT1 and ERK/2 proteins. The levels of Egf, Notch1, Mkk7 and phosphorylation of AKT1 and ERK/2 increased in Anxa1 KO mice but decreased in Anxa1 OE mice. Taken together, our results suggested that ANXA1 could affect the hair growth by regulating the HFSCs proliferation through EGF signaling pathway.

Single-bundle posterior cruciate ligament reconstruction with remnant preservation: lateral versus medial-sided augmentation technique.

OBJECTIVE: To compare the results of lateral versus medial-sided augmentation techniques in single-bundle posterior cruciate ligament (PCL) reconstruction with remnant preservation. METHODS: Forty-two cases of isolated chronic PCL ruptures were reconstructed in a single-bundle manner with remnant preservation. The patients were randomly separated into two groups: in the medial-sided augmentation (MSA) group the graft passed through the medial side of the remnant and in the lateral-sided augmentation (LSA) group it passed through the lateral side. RESULTS: Nineteen patients in the MSA group and 17 in the LSA group were followed up for a minimum of 2 years. At the final follow-up, the average side-to-side differences in posterior laxity were 1.6 ± 1.2 mm and 1.5 ± 1.3 mm respectively in the MSA and LSA groups. According to the International Knee Documentation Committee (IKDC) scale, patient numbers graded as normal, nearly normal and abnormal were 14 (73.7%), 4 (21.1%), and 1 (5.3%) in the MSA group, and 13 (76.5%), 3 (17.6%), and 1 (5.9%) in the LSA group. The IKDC subjective scores were 93.1 ± 3.8 and 92.6 ± 4.1, the Lysholm scores were 95.0 ± 4.6 and 93.7 ± 4.2, and the Tegner scores were 5.4 ± 0.9 and 5.6 ± 0.7 respectively in the MSA and LSA groups. Statistical analysis showed no significant differences between the MSA and the LSA group regarding all subjective and objective results. CONCLUSION: In single-bundle PCL reconstruction with remnant preservation, similar subjective and objective results can be obtained with MSA and LSA techniques.