Publications

The integrin alphavbeta6 is expressed on a variety of epithelial cells during dynamic processes including organogenesis, tissue injury and malignant transformation. However, because of the lack of tools to specifically inhibit the function of this integrin, little is known about its effects on cell behavior. To directly examine the role of this integrin in cell migration, we used keratinocytes derived from wild-type mice or mice expressing a null mutation in the beta6 subunit (beta6-/-) to perform migration assays in vitro. Migration on the known alphavbeta6 ligand, fibronectin was reduced in keratinocytes from beta6-/- mice. Interestingly, keratinocytes from beta6-/- mice also demonstrated markedly reduced migration on vitronectin, a protein not previously known to be a ligand for alphavbeta6. An anti-alphavbeta6 monoclonal antibody 10D5, generated by immunization of beta6-/- mice with murine keratinocytes, inhibited adhesion and migration of wild-type keratinocyte on both vitronectin and fibronectin to levels similar to those seen with keratinocytes from beta6-/- mice. alphavbeta6-mediated migration on both ligands was dramatically augmented by treatment with phorbol myrisate acetate (PMA) or with hepatocyte growth factor, and augmentation of migration by either stimulus could be abolished by the PKC inhibitor GF109203X, suggesting a critical role for PKC in enhancement of alphavbeta6-mediated cell migration.

OBJECTIVE

To evaluate the impact of patient demographics, clinical features, and job-related factors on the time until return to work after carpal tunnel release surgery.

METHODS

We employed a cross-sectional community-based study of 59 patients who had undergone carpal tunnel release surgery. Sociodemographic, clinical, and job-related characteristics and time to return to work were obtained by interview and from medical records. Exposure to ergonomic risk was derived from an independently validated job matrix. Time to return to work after surgery was analyzed by survival techniques.

RESULTS

Median time to return to work was 5 weeks. After adjustment, the relative rate (RR) of return to work per week after surgery was most strongly decreased by the receipt of workers' compensation, RR 0.2 (95% confidence interval [CI] 0.1-0.5), and by the exposure to bending and twisting of the hand prior to surgery, RR 0.7 (95% CI 0.5-0.9) per hour. Female gender was another predictor of decreased return to work, RR 0.5 (95% CI 0.3-0.8).

CONCLUSIONS

Patients receiving workers' compensation, those exposed to higher levels of bending and twisting of their hands and wrists, and women were slower to return to work after carpal tunnel release surgery.