Experience with the Amplatz retrievable vena caval filter. Work in progress

The Amplatz retrievable vena caval filter was designed in an attempt to decrease complications associated with the placement of Mobin-Uddin or Kimray-Greenfield filters. The design allows percutaneous retrieval, thus expanding application of the filter to situations requiring temporary prophylaxis against pulmonary embolism. Filters have been placed in 16 patients, nine (56%) for prophylactic purposes. All filters were easily inserted percutaneously. Complications occurred in three patients; these included complete thrombosis of the inferior vena cava below the filter, misplacement of one filter into the pericaval retroperitoneal tissue, and development of thrombus cranial to the filter. With the current introduction system, the possibility of filter misplacement has been essentially eliminated. No patient experienced symptoms suggestive of pulmonary embolism after filter insertion. One filter retrieval has been performed, with no complications.     

Effect of medial arch-heel support in inserts on reducing ankle eversion: a biomechanics study

Background  

Excessive pronation (or eversion) at ankle joint in heel-toe running correlated with lower extremity overuse injuries. Orthotics and inserts are often prescribed to limit the pronation range to tackle the problem. Previous studies revealed that the effect is product-specific. This study investigated the effect of medial arch-heel support in inserts on reducing ankle eversion in standing, walking and running.     

Growth characteristics of ChimeriVax-Den vaccine viruses in Aedes aegypti and Aedes albopictus from Thailand

Four chimeric yellow fever (YF) 17D-dengue (DEN) candidate vaccine viruses (ChimeriVax-DEN; Acambis, Cambridge, MA) were characterized in Aedes aegypti and Ae. albopictus mosquitoes collected from Thailand. The four vaccine viruses contained the relevant prM and E genes of wild-type dengue viruses (DENV; serotypes 1-4) substituted for the equivalent genes in the YF vaccine virus (17D) backbone. Each chimera conferred protection against the homologous DENV serotype; a tetravalent mix of all four chimeras stimulates an immune response against all serotypes. Field-collected mosquitoes from Thailand were fed on blood containing each of the viruses under study and held 21 days after infection. Infection and dissemination rates were based on antigen detection in the body or head tissues, respectively. All four wild-type DENV serotypes infected and disseminated, but the candidate vaccine viruses were highly attenuated in mosquitoes with respect to infection and especially with respect to dissemination. Considering the low level viremias anticipated in humans vaccinated with these viruses, it is predicted that the risks of infection and transmission by mosquitoes in nature is minimal.     

The revised global yellow fever risk map and recommendations for vaccination, 2010: consensus of the Informal WHO Working Group on Geographic Risk for Yellow Fever

The changing epidemiology of yellow fever and continued reports of rare but serious adverse events associated with yellow fever vaccine have drawn attention to the need to revisit criteria for the designation of areas with risk for yellow fever virus activity, and to revise the vaccine recommendations for international travel. WHO convened a working group of international experts to review factors important for the transmission of yellow fever virus and country-specific yellow fever information, to establish criteria for additions to or removal from the list of countries with risk for yellow fever virus transmission, to update yellow fever risk maps, and to revise the recommendations for vaccination for international travel. This report details the recommendations made by the working group about criteria for the designation of risk and specific changes to the classification of areas with risk for transmission of yellow fever virus.     

Intranasal monoclonal immunoglobulin A against respiratory syncytial virus protects against upper and lower respiratory tract infections in mice.

The role of secretory antibody in protection against respiratory syncytial virus (RSV) infection was examined by using monoclonal immunoglobulin A (IgA) antibody for intranasal passive immunization of mice. Eight anti-RSV IgA hybridomas were produced by fusing myeloma cells with lung lymphocytes from RSV-immunized mice. Five IgA antibodies recognized RSV strains of both the A and the B subgroups, and two of these neutralized virus in a plaque reduction assay. Monoclonal IgA antibody HNK20, which bound to F glycoprotein, was most effective, reducing plaques by 50% at a concentration of 0.1 microgram/ml for both subgroup A and subgroup B strains. HNK20 also neutralized all of eight clinical isolates of RSV tested. When delivered intranasally to mice 24 h prior to RSV challenge, HNK20 reduced virus titers in the lungs by nearly 100-fold. Maximal protection occurred at a dose of 0.5 mg/kg of body weight. Significant protection against lung infection was seen when the interval between antibody treatment and challenge was as long as 72 h. HNK20 also decreased virus titers in the nose approximately 10-fold when given 1 h, but not 24 h, before challenge. When mice were treated with HNK20 intranasally 3 days after challenge, viral titers were reduced in the lungs but not the nose. The results indicate that topical application of relatively small amounts of monoclonal IgA can protect against both upper and lower respiratory tract infections caused by RSV.     

Induction of NK activity in large granular lymphocyte leukemia: activation with anti-CD3 monoclonal antibody and interleukin 2

Large granular lymphocyte (LGL) leukemia is a rare disease characterized by clonal expansion of LGL associated with chronic neutropenia, multiple auto-antibodies, and occasionally polyarthritis. We studied cell surface antigen expression and functional activity of leukemic LGL from ten such patients. Using two-color flow cytometric analysis, we found that leukemic LGL from all ten patients expressed the CD3 and HNK-1 markers, while cells from only four patients expressed IgG Fc receptors (FcR). The LGL leukemic cells had little or no NK activity (defined as MHC-nonrestricted cytotoxicity against K562 target cells); however, NK activity could be induced in leukemic LGL by in vitro treatment with as little as 0.05 microgram/mL of anti-CD3 monoclonal antibody. Cell sorting experiments demonstrated that NK activity was induced in CD3+ leukemic LGL (either CD3+, HNK-1+ or CD3+, FcR+) with anti-CD3 monoclonal antibody but not in normal CD3+, FcR- T cells. Treatment with purified interleukin 2 (IL 2) also caused direct activation of some CD3+ leukemic LGL. Despite induction with anti-CD3 MAb or IL 2, activated leukemic LGL did not proliferate or express high density IL 2 receptors detectable by cell sorter analysis. Treatment with alpha interferon had minimal effect on NK activity of LGL leukemic cells. These results suggest that leukemic LGL may provide a useful model for examining the signals required for LGL maturation and activation.