Complement and the control of HIV infection: an evolving story.

PURPOSE OF REVIEW: Thirty years ago, investigators isolated and later determined the structure of HIV-1 and its envelope proteins. Using techniques that were effective with other viruses, they prepared vaccines designed to generate antibody or T-cell responses, but they were ineffective in clinical trials. In this article, we consider the role of complement in host defense against enveloped viruses, the role it might play in the antibody response and why complement has not controlled HIV-1 infection. RECENT FINDINGS: Complement consists of a large group of cell-bound and plasma proteins that are an integral part of the innate immune system. They provide a first line of defense against microbes and also play a role in the immune response. Here we review the studies of complement-mediated HIV destruction and the role of complement in the HIV antibody response. SUMMARY: HIV-1 has evolved a complex defense to prevent complement-mediated killing reviewed here. As part of these studies, we have discovered that HIV-1 envelope, on administration into animals, is rapidly broken down into small peptides that may prove to be very inefficient at provident the type of antigenic stimulation that leads to an effective immune response. Improving complement binding and stabilizing envelope may improve the vaccine response.

A comparison of preoperative airway assessment techniques: the modified Mallampati and the upper lip bite test.

The purpose of this study was to compare the preoperative anesthetic airway evaluation methods of the modified Mallamapti test (MMT) and upper lip bite test (ULBT) with the direct laryngoscopic views obtained during tracheal intubation. Positive relationships were predicted for the MMT and ULBT with direct laryngoscopic view and between the MMT and ULBT. We assessed 50 patients' airways preoperatively by MMT and ULBT. Intraoperatively, laryngoscopic views were graded on the Cormack and Lehane scale. Descriptive statistics and correlations were computed. There was no relationship between the MMT and the ULBT and the Cormack and Lehane scale. There was a significant relationship between the ULBT and the Cormack and Lehane scale (r = 0.512; P <.001 ). The ULBT was superior to the MMT in every measure in this study: sensitivity (55% vs 11%), specificity (97% vs 75%), positive predictive value (83% vs 9%), and accuracy (90% vs 64%). The findings of this study support those of a previous study of the ULBT. Because of the ease of the ULBT and the promising results of this small study, we recommend further research with a larger, more diverse sample.