Immunologic and pharmacologic concepts of monoclonal antibodies

While monoclonal antibodies have solved many of the difficulties of using immunologic reagents for radioimmunodiagnosis and therapy, in the 13 years since their introduction a number of persistent problems remain, most notably a low yield of antibody-producing cells from the fusion process, difficulty in obtaining high-affinity antibodies, and the potential immunogenicity of murine immunoglobulins (Igs). Several solutions are under development, including fusion techniques that enrich for cells producing desired antibodies, production of human-mouse chimeric antibodies by recombinant DNA technology, and the generation of human monoclonal antibodies by promising new approaches. Until these upcoming methodologies are established, and to better direct their development and application, a sound understanding of the pharmacology of presently available native and modified monoclonal antibodies is crucial. Although much has been already determined in this area, a great deal of further clarification remains necessary.     

Review of facial muscle spasms

Facial muscle spasms, which are rare in adults, present a particularly difficult entity for the optometrist to recognise. The condition may not even manifest itself at an eye examination and the optometrist may have to rely on subjective symptoms to assist in the recognition of the condition. It is important to diagnose the condition correctly as specific and effective treatment is available.     

Large volume injection and infiltration system

Summary A system which can be used for injection or infiltration of large volumes of fluid is described. This consists of a syringe which fills automatically from a reservoir through an inlet/outlet valve.     

Evaluation of the debonding characteristics of 2 ceramic brackets: an in vitro study.

The objectives of this study were to evaluate and compare the shear bond strengths and bond failure locations of 2 currently available orthodontic ceramic brackets. Forty polycrystalline ceramic brackets (Clarity, 3M Unitek, Monrovia, Calif) and 40 monocrystalline ceramic brackets (Inspire, Ormco, Orange, Calif) were bonded to 80 extracted premolars with the same bonding system. All bonded specimens were placed in distilled water for 42 hours at 37 degrees C followed by thermal cycling for 700 complete cycles. Forty ceramic brackets, 20 of each type, were tested on a universal testing machine to determine the shear force levels required to debond them. Forty ceramic brackets were removed with the debonding pliers recommended by the manufacturers. All teeth were examined under an optical microscope, and the adhesive remnant index was used to assess the bond failure locations. The mean shear bond strength of the Clarity brackets was 21.67 +/- 5.19 MPa, and the mean shear bond strength of the Inspire brackets was 20.32 +/- 8 MPa. The mean shear bond strengths of both brackets were higher than those considered clinically optimal. Most of the brackets (85% of Clarity and 75% of Inspire) tested on the machine failed at the bracket-adhesive interface. One premolar bonded with an Inspire bracket had enamel fracture upon debonding. Most of the brackets (90% of Clarity and 95% of Inspire) debonded with pliers failed at the bracket-adhesive interface. No enamel damage was evident in any specimen when the brackets were removed with the appropriate pliers. The results indicate that the safest way to remove ceramic brackets with respect to reducing the chance of enamel damage is to use the debonding technique specifically designed for each.