Identification of stages of amelogenesis in the continuously growing mandiblular incisor of C57BL/6J male mice throughout life using molar teeth as landmarks.

Continuously growing mouse incisors are widely used to study amelogenesis, since all stages of this process (., secretory, transition and maturation) are present in a spatially determined sequence at any given time. To study biological changes associated with enamel formation, it is important to develop reliable methods for collecting ameloblasts, the cells that regulate enamel formation, from different stages of amelogenesis.

Elucidating the role of keratin 75 in enamel using Krt75 knock-in mouse model.

Keratin 75 (K75) was recently discovered in ameloblasts and enamel organic matrix. Carriers of A161T substitution in K75 present with the skin condition . This mutation is also associated with high prevalence of caries and compromised structural and mechanical properties of enamel.

Changes in students' attitudes toward HIV-infected patients as the students progress through medical school.

Purpose: To examine how medical students' attitudes and intentions toward the treatment of persons infected with human immunodeficiency virus (HIV) changed as the students progressed through medical school.

Method: Similar 44-item self-administered questionnaires, to be completed anonymously, were given to 394 medical students at the University of Michigan Medical School in February 1989, when the students were in their first or second years, and to 378 of the same students in February 1991, when they were in their third or fourth years. Seven subscale variables were created, and their effects on students' willingness to treat HIV-infected patients were assessed.