Purpose Human eyes with exfoliation syndrome (XFS) exhibit a distinctive pattern of iris transillumination defects that are recapitulated in Lyst mutant mice carrying the beige allele. The purpose of this study was to determine the anatomic basis for Lyst-mediated transillumination defects, test whether Lyst mutant mice develop other features of XFS, and describe the molecular basis of the beige mutation. Methods Lyst mutant mice and strain-matched controls were compared by clinical, histologic, immunohistochemical, and molecular genetic analyses. Results Slit-lamp examination showed that Lyst mutant mice uniformly exhibit XFS-like transillumination defects. Histologic analysis showed that these defects correlate with a sawtooth morphology of the iris pigment epithelium. Lyst mutant mice also produce an exfoliative-like material and exhibit pronounced pigment dispersion. Despite these insults, Lyst mutation does not cause increased intraocular pressure or optic nerve damage in the C57BL/6J genetic background. Sequence analysis identified that the beige mutation is predicted to delete a single isoleucine from the WD40 domain of the LYST protein, suggesting that this mutation is likely to disrupt a protein-protein interaction. Conclusions Lyst mutant eyes exhibit multiple features of XFS. Recent human genetic association studies have identified changes occurring in the LOXL1 gene as an important risk factor for XFS but also indicated that other factors contributing to risk likely exist. These results demonstrated that mutation of the Lyst gene can produce ocular features of human XFS and suggested that LYST or LYST-interacting genes may contribute to XFS.

Psychological momentum has been an elusive phenomenon in sport psychology research. The present study utilized a two-round free-throw shooting contest between pairs of participants to examine factors which influenced participants' perceptions of momentum and subsequent changes in performance. Factors hypothesized to contribute to perceptions of momentum were divided into three categories of Personal Variables, Situational Variables, and Self-ratings of Performance. Perceptions of momentum could be significantly predicted by both Situational Variables and Self-ratings of Performance. Changes in performance, however, were only significantly predicted by Situational Variables. These findings support the notion that attributions of positive and negative psychological momentum function simply as a labeling process in the evaluation of performance, with little or no effect on subsequent performance. Based on these findings and other research on psychological momentum, a theoretical model (Projected Performance Model) is proposed to conceptualize more clearly fluctuations in performance and their relationship to the construct of psychological momentum.

Murine CCT has been measured with a variety of different techniques, but only among a limited number of different strains. Here, pachymetry was established as an additional tool and used to conduct a broad survey of different strains of inbred mice. These results demonstrated that murine CCT was highly influenced by genetic background and established a baseline for future genetic approaches to further elucidate mechanisms regulating CCT and its disease associations.

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