Screening of selected male blood donors for p24 antigen of human immunodeficiency virus type 1. The Transfusion Safety Study Group

BACKGROUND. The p24 antigen of human immunodeficiency virus type 1 (HIV-1) is sometimes detected before antibody (anti-HIV-1) is detectable in the serum of recently infected persons. This has led to the consideration of p24-antigen testing for routine screening of blood donors. METHODS. To estimate how many HIV-infected seronegative donors would be identified if p24-antigen screening was introduced, we tested selected donations from a repository of 200,000 serum samples from voluntary donors that was established in late 1984 and early 1985. The 8597 serum samples selected for p24-antigen screening were chosen because their donors had demographic characteristics known to be associated with a high prevalence of seropositivity. RESULTS. The prevalence of anti-HIV-1 antibodies in the 1984-1985 serum samples selected for p24-antigen screening was 1.54 percent--more than 100 times the 0.012 percent prevalence in present-day donations in the United States. The antigen was detected in 15 of 132 serum samples (11.4 percent) from donors who had already been confirmed as seropositive. No instance of confirmed positivity for p24 antigen was found among the 8465 seronegative serum samples. CONCLUSIONS. These data indicate that the yield of screening for p24 antigen in volunteer donors to identify HIV-1 carriers would be negligible. We therefore recommend against routine screening with currently available p24-antigen assays.     

HER2 protein overexpression in estrogen receptor-positive ductal carcinoma in situ of the breast: frequency and implications for tamoxifen therapy.

Recent clinical data have suggested that the efficacy of tamoxifen in reducing the risk of local recurrence following lumpectomy and radiation therapy in patients with ductal carcinoma in situ (DCIS) is limited to patients with estrogen receptor (ER)-positive lesions. However, it is currently not known if HER2 protein overexpression might be associated with reduced tamoxifen benefit in patients with ER-positive DCIS, as has been suggested in patients with ER-positive invasive breast cancer and in preclinical models. Moreover, the frequency of HER2 overexpression in ER-positive ductal carcinoma in situ has not been previously evaluated in detail. To address this issue, we studied ER expression and HER2 overexpression in 148 cases of DCIS using a sensitive double immunostaining technique and assessed the frequency of ER expression and HER2 overexpression in relation to each other and in relation to DCIS grade. Overall, ER expression was seen in 114 cases (77%) and HER2 protein overexpression was seen in 42 cases (28%). Of 114 ER-positive ductal carcinoma in situ, 14 (12%) showed concurrent HER2 protein overexpression, and all 14 of these DCIS lesions were of high nuclear grade. In addition, in all 14 ER-positive DCIS cases that showed HER2 overexpression, double immunostaining demonstrated that ER and HER2 protein were coexpressed by the same neoplastic cells. We conclude that a subset of ER-positive DCIS show concomitant overexpression of HER2 protein. Whether or not HER2 overexpression is associated with a diminished response to tamoxifen in patients with ER-positive DCIS will require investigation in clinical outcome studies.     

Receptor-mediated recognition of Cryptococcus neoformans.

Cryptococcus neoformans, a facultative intracellular pathogen of macrophages, is unique among medically important fungi in its possession of a polysaccharide capsule. Capsule represents the organism's major virulence factor. In the absence of opsonins, binding of encapsulated C. neoformans to macrophages is minimal. Following incubation in serum, C. neoformans potently activates complement, resulting in surface deposition of the third component of complement. Macrophages bind and phagocytose opsonized C. neoformans via three major complement receptors (CR) for C3 fragments, designated CD35 (CR1), CD11b/CD18 (CR3), and CD11c/CD18 (CR4). Antibody in normal human serum generally lacks opsonic activity, although vaccination can elicit anticapsular antibodies that are opsonic. The major component of cryptococcal capsule, glucuronoxylomannan (GXM), is shed from the fungus and circulates in the blood and cerebrospinal fluid of patients with cryptococcosis. Cellular receptors defined for GXM include CD14, toll-like receptor-2, toll-like receptor-4, and CD18. GXM binding to macrophage receptors triggers activation of nuclear factor-kB, but not mitogen-activated protein kinases. This results in no proinflammatory gene expression or release. C. neoformans also secretes mannoproteins, which are recognized by mannose receptors as well as by mannose-binding lectin, perhaps in conjunction with CD14. Strategies directed at modulating how intact C. neoformans and its released components are recognized by phagocytes could lead to novel approaches to treating cryptococcosis     

Quantitative enzyme cytochemistry of leukaemic cells

A new technique for the quantitative estimation of glycolytic and respiratory enzyme activity in intact and unfixed bone marrow and peripheral blood cells is described. The method gives a two- to three-fold increase in demonstrable enzyme activity per cell compared with existing techniques using fixed marrow film preparations, and is particularly applicable to the study of relatively fragile cells such as the leukaemic lymphoblast.     

Domains-based outcomes assessment of continuing medical education: the VA's model.

Demonstrating outcomes of continuing medical education (CME) efforts has become increasingly important to CME providers, accrediting organizations, and licensing bodies. Many CME providers have difficulty defining the nature of the outcomes, much less documenting the outcomes for which they are responsible. The vague nature of the terms "outcome," "impact," or "result" in the complexity of health care and medical education environments is a particular obstacle to many education providers. To overcome these barriers, the VA's Employee Education System (EES), a large CME provider, created a model identifying five major domains of possible outcomes for CME interventions; these are the domains of individual participants, employee teams, the larger organization, patients, and the community. These domains are useful in either assessing a single CME activity's outcomes or comprehensively assessing a CME provider's outcomes-assessment strategy. The use of such a domains-based outcomes-management strategy links organizational mission, needs assessment, specific activity assessment, and assessment of the overall education program. This approach may be useful to CME providers, accrediting and licensing bodies, or others interested in the relationship of CME outcomes to the activities of CME providers.     

The mutational spectrum of brachydactyly type C

Growth/differentiation factor-5 (GDF5), also known as cartilage-derived morphogenetic protein-1 (CDMP-1), is a secreted signaling molecule that participates in skeletal morphogenesis. Heterozygous mutations in GDF5, which maps to human chromosome 20, occur in individuals with autosomal dominant brachydactyly type C (BDC). Here we show that BDC is locus homogeneous by reporting a GDF5 frameshift mutation segregating with the phenotype in a family whose trait was initially thought to map to human chromosome 12. We also describe heterozygous mutations in nine additional probands/families with BDC and show nonpenetrance in a mutation carrier. Finally, we show that mutant GDF5 polypeptides containing missense mutations in their active domains do not efficiently form disulfide-linked dimers when expressed in vitro. These data support the hypothesis that BDC results from functional haploinsufficiency for GDF5.     

Reed-Sternberg/lymphocyte rosette: lymphocyte subpopulations as defined by monoclonal antibodies

The Reed-Sternberg cell/lymphocyte rosette characteristic of Hodgkin's disease tissue and cell suspensions was investigated with monoclonal antibodies on fresh viable cell suspensions prepared from nine cases of Hodgkin's disease. The biopsy material comprised six spleens and three lymph nodes. The majority of the rosetting lymphocytes were T cells, primarily of the helper subset. Some of the attached lymphocytes were suppressor T cells. In addition, a few of the rosetting lymphocytes around Reed-Sternberg cells were B cells.     

Replacing the academic medical center's teaching hospital.

Addressing the need for updated teaching hospital facilities is one of the most significant issues that an academic medical center faces. The authors describe the process they underwent in deciding to build a new facility at the Medical University of South Carolina (MUSC). Initial issues included whether or not the teaching hospital would continue to play a role in clinical education and whether to replace or renovate the existing facility. Once the decision to build was reached, MUSC had to choose between an on-campus or distant site for the new hospital and determine what the function of the old hospital would be. The authors examine these questions and discuss the factors involved in different stages of decision making, in order to provide the academic medicine community guidance in negotiating similar situations. Open communication within MUSC and with the greater community was a key component of the success of the enterprise to date. The authors argue that decisions concerning site, size, and focus of the hospital must be made by developing university-wide and community consensus among many different constituencies. The most important elements in the success at MUSC were having unified leadership, incorporating constituent input, engaging an external consultant, remaining unfazed by unanticipated challenges, and adhering to a realistic, aggressive timetable. The authors share their strategies for identifying and successfully managing these complex and potentially divisive aspects of building a new teaching hospital.     

Mucosal immunization with PLGA-microencapsulated DNA primes a SIV-specific CTL response revealed by boosting with cognate recombinant modified vaccinia virus Ankara

Systemically administered DNA encoding a recombinant human immunodeficiency virus (HIV) derived immunogen effectively primes a cytotoxic T lymphocyte (CTL) response in macaques. In this further pilot study we have evaluated mucosal delivery of DNA as an alternative priming strategy. Plasmid DNA, pTH.HW, encoding a multi-CTL epitope gene, was incorporated into poly(D,L-lactic-co-glycolic acid) microparticles of less than 10 microm in diameter. Five intrarectal immunizations failed to stimulate a circulating vaccine-specific CTL response in 2 Mamu-A*01(+) rhesus macaques. However, 1 week after intradermal immunization with a cognate modified vaccinia virus Ankara vaccine MVA.HW, CTL responses were detected in both animals that persisted until analysis postmortem, 12 weeks after the final boost. In contrast, a weaker and less durable response was seen in an animal vaccinated with the MVA construct alone. Analysis of lymphoid tissues revealed a disseminated CTL response in peripheral and regional lymph nodes but not the spleen of both mucosally primed animals.