The American Medical Association: Membership reaction to public relations practices

Thesis (M.S.)--Boston Universit

Analysis of sFlt Isoforms as Biomarkers for the Development of Preeclampsia

Preeclampsia is a multi-system disorder characterized by hypertension, edema and proteinuria affecting between 5-10% of pregnancies. A subset of cases progress to severe preeclampsia with exacerbated hypertension/proteinuria and evidence of nervous system, liver and/or kidney dysfunction, in addition to fetal growth restriction. Soluble fms-like tyrosine kinase-1 (sFlt) is minimally expressed in many tissues, including the placenta, and is a circulating antagonist to vascular endothelial growth factor. With progression of pregnancy, sFlt levels significantly rise, especially in women who develop preeclampsia. Diagnostic tests to predict preeclampsia in pregnant women are limited and current tests measure total sFlt in relationship to placental growth factor with varying sensitivity and specificity. We hypothesized that a pregnancy-specific splice variant of sFlt (sFlt1-14), almost exclusively expressed by the placenta, would serve as an improved serum biomarker for the development of preeclampsia. Monoclonal antibodies (mAbs) were developed that specifically bind the two predominant isoforms of sFlt (sFlt1 and sFlt1-14) by hybridoma generation from wild type mice immunized with c-terminal peptides of the two isoforms. Western blot, ELISA and affinity analysis indicated the mAbs were specific for sFlt1 or sFlt1-14 splice variants and recognized these proteins in biological fluids (amniotic fluid or serum). A quantitative capture ELISA was developed whereby total sFlt in biological fluid is captured by a unique human mAb and specific levels of sFlt1 or sFlt1-14 are detected by their respective mouse mAb, followed by anti-murine secondary antibody development. Using recombinant sFlt1 or sFlt1-14 as standards, these endogenous proteins were quantified in commercially available third trimester human pregnant sera. Future studies will measure these isoforms in sera prospectively collected from women with known outcomes of a healthy pregnancy or preeclampsia and the ability of absolute quantitation of the isoform(s) or a ratio of the two to predict the likely onset and severity of preeclampsia will be evaluated

Therapeutic Monoclonal Antibodies to Prevent Tuberculosis Infection

Mycobacteria tuberculosis (Mtb) is a major cause of human morbidity and mortality. Transmission occurs through inhalation of aerosolized Mtb and the initial infection is believed to occur primarily in the alveolar macrophage, although Mtb can infect other cells residing in the lung including dendritic cells, pneumocytes and M cells. Several molecules derived from Mtb are involved in the attachment of the organism to host receptors (opsonic and non-opsonic), which have been reasonably well elucidated. However, a complete understanding of how Mtb attaches to the host and the relative importance of each mechanism on the outcome of infection remains elusive. We hypothesize that protection from infection is possible by blocking the critical initial surface interactions of the organism with the host cell using specific monoclonal antibodies (mAbs). To develop effective mAbs, the outermost layers of Mtb, the capsule and outer membrane, were isolated and characterized by protein gel and LC/MS/MS. Approximately 1000 different proteins were identified in the isolations, of which ~25% were unique to one of the two fractions. The capsule or outer membrane preparations were used as antigens to immunize CD1 mice for up to 12 weeks to generate antibodies via traditional hybridoma generation. Antibodies were screened, selected and characterized by their ability to bind whole cell Mtb by ELISA, demonstration of unique heavy chain variable region sequence and binding specificity by Western Blot. Of approximately 1500 screened hybridomas, 30 lead mAbs have been isolated with specificity to various targets. Preliminary results suggest several of the lead mAb candidates are able to prevent Mtb-induced macrophage cell death in vitro. Future studies will attempt to confirm efficacy in vivo after aerosolized infection in mice with mAb-coated Mtb or parenteral administration of mAb(s). Targets of functional mAbs will be determined and these antigens could serve as viable candidates for vaccine development

A mission control architecture for robotic lunar sample return as field tested in an analogue deployment to the Sudbury impact structure

A Mission Control Architecture is presented for a Robotic Lunar Sample Return Mission which builds upon the experience of the landed missions of the NASA Mars Exploration Program. This architecture consists of four separate processes working in parallel at Mission Control and achieving buy-in for plans sequentially instead of simultaneously from all members of the team. These four processes were: Science Processing, Science Interpretation, Planning and Mission Evaluation. Science Processing was responsible for creating products from data downlinked from the field and is organized by instrument. Science Interpretation was responsible for determining whether or not science goals are being met and what measurements need to be taken to satisfy these goals. The Planning process, responsible for scheduling and sequencing observations, and the Evaluation process that fostered inter-process communications, reporting and documentation assisted these processes. This organization is advantageous for its flexibility as shown by the ability of the structure to produce plans for the rover every two hours, for the rapidity with which Mission Control team members may be trained and for the relatively small size of each individual team. This architecture was tested in an analogue mission to the Sudbury impact structure from June 6-17, 2011. A rover was used which was capable of developing a network of locations that could be revisited using a teach and repeat method. This allowed the science team to process several different outcrops in parallel, downselecting at each stage to ensure that the samples selected for caching were the most representative of the site. Over the course of 10 days, 18 rock samples were collected from 5 different outcrops, 182 individual field activities - such as roving or acquiring an image mosaic or other data product - were completed within 43 command cycles, and the rover travelled over 2,200 m. Data transfer from communications passes were filled to 74%. Sample triage was simulated to allow down-selection to 1kg of material for return to Earth

Dedifferentiation and Proliferation of Mammalian Cardiomyocytes

It has long been thought that mammalian cardiomyocytes are terminally-differentiated and unable to proliferate. However, myocytes in more primitive animals such as zebrafish are able to dedifferentiate and proliferate to regenerate amputated cardiac muscle.Here we test the hypothesis that mature mammalian cardiomyocytes retain substantial cellular plasticity, including the ability to dedifferentiate, proliferate, and acquire progenitor cell phenotypes. Two complementary methods were used: 1) cardiomyocyte purification from rat hearts, and 2) genetic fate mapping in cardiac explants from bi-transgenic mice. Cardiomyocytes isolated from rodent hearts were purified by multiple centrifugation and Percoll gradient separation steps, and the purity verified by immunostaining and RT-PCR. Within days in culture, purified cardiomyocytes lost their characteristic electrophysiological properties and striations, flattened and began to divide, as confirmed by proliferation markers and BrdU incorporation. Many dedifferentiated cardiomyocytes went on to express the stem cell antigen c-kit, and the early cardiac transcription factors GATA4 and Nkx2.5. Underlying these changes, inhibitory cell cycle molecules were suppressed in myocyte-derived cells (MDCs), while microRNAs known to orchestrate proliferation and pluripotency increased dramatically. Some, but not all, MDCs self-organized into spheres and re-differentiated into myocytes and endothelial cells in vitro. Cell fate tracking of cardiomyocytes from 4-OH-Tamoxifen-treated double-transgenic MerCreMer/ZEG mouse hearts revealed that green fluorescent protein (GFP) continues to be expressed in dedifferentiated cardiomyocytes, two-thirds of which were also c-kit(+).Contradicting the prevailing view that they are terminally-differentiated, postnatal mammalian cardiomyocytes are instead capable of substantial plasticity. Dedifferentiation of myocytes facilitates proliferation and confers a degree of stemness, including the expression of c-kit and the capacity for multipotency

Progress and challenges in the vaccine-based treatment of head and neck cancers

Head and neck (HN) cancer represents one of the most challenging diseases because the mortality remains high despite advances in early diagnosis and treatment. Although vaccine-based approaches for the treatment of advanced squamous cell carcinoma of the head and neck have achieved limited clinical success, advances in cancer immunology provide a strong foundation and powerful new tools to guide current attempts to develop effective cancer vaccines. This article reviews what has to be rather what has been done in the field for the development of future vaccines in HN tumours