Clinical oversight and the avoidance of repeat induced abortion.

Objective: To evaluate the impact of patient counseling, demographics, and contraceptive methods on repeat induced abortion in women attending family planning clinics.

Methods: A retrospective chart review of repeat induced abortions was performed. The analysis included patients with an initial induced abortion obtained between January 1, 2001, and March 31, 2014, at New York City Health + Hospitals/Metropolitan.

Patterned Threadlike Micelles and DNA-Tethered Nanoparticles: A Structural Study of PEGylated Cationic Liposome-DNA Assemblies.

The self-assembly of oppositely charged biomacromolecules has been extensively studied due to its pertinence in the design of functional nanomaterials. Using cryo electron microscopy (cryo-EM), optical light scattering, and fluorescence microscopy, we investigated the structure and phase behavior of PEGylated (PEG: poly(ethylene glycol)) cationic liposome-DNA nanoparticles (CL-DNA NPs) as a function of DNA length, topology (linear and circular), and ρ(chg) (the molar charge ratio of cationic lipid to anionic DNA). Although all NPs studied exhibited lamellar internal nanostructure, NPs formed with short (∼2 kbps), linear, polydisperse DNA were defect-rich and contained smaller domains.

Uptake and transfection efficiency of PEGylated cationic liposome-DNA complexes with and without RGD-tagging.

Steric stabilization of cationic liposome-DNA (CL-DNA) complexes is required for in vivo applications such as gene therapy. PEGylation (PEG: poly(ethylene glycol)) of CL-DNA complexes by addition of PEG2000-lipids yields sterically stabilized nanoparticles but strongly reduces their gene delivery efficacy. PEGylation-induced weakening of the electrostatic binding of CL-DNA nanoparticles to cells (leading to reduced uptake) has been considered as a possible cause, but experimental results have been ambiguous.

Automation in single-particle electron microscopy connecting the pieces.

Throughout the history of single-particle electron microscopy (EM), automated technologies have seen varying degrees of emphasis and development, usually depending upon the contemporary demands of the field. We are currently faced with increasingly sophisticated devices for specimen preparation, vast increases in the size of collected data sets, comprehensive algorithms for image processing, sophisticated tools for quality assessment, and an influx of interested scientists from outside the field who might lack the skills of experienced microscopists. This situation places automated techniques in high demand.

A toolbox for ab initio 3-D reconstructions in single-particle electron microscopy.

Structure determination of a novel macromolecular complex via single-particle electron microscopy depends upon overcoming the challenge of establishing a reliable 3-D reconstruction using only 2-D images. There are a variety of strategies that deal with this issue, but not all of them are readily accessible and straightforward to use. We have developed a "toolbox" of ab initio reconstruction techniques that provide several options for calculating 3-D volumes in an easily managed and tightly controlled work-flow that adheres to standard conventions and formats.

Cutting edge: antigen presentation to CD8 T cells after influenza A virus infection.

Influenza A virus infection induces massive inflammation and lung damage. Activation of CD8 T cells by dendritic cells (DCs) is necessary to control disease. We undertook studies to track directly Ag presentation to CD8 T cells in vivo through the first 72 h after infection with OVA-expressing influenza A virus.

Protection against influenza A virus by memory CD8 T cells requires reactivation by bone marrow-derived dendritic cells.

Influenza A virus is the causative agent of an acute inflammatory disease of the airway. Although Abs can prevent infection, disease and death can be prevented by T cell-mediated immunity. Recently, we showed that protection against lethal influenza A (PR8/34) virus infection is mediated by central memory CD8 T cells (T(CM)).

MHC class II deprivation impairs CD4 T cell motility and responsiveness to antigen-bearing dendritic cells in vivo.

The role continuous contact with self-peptide/MHC molecules (self ligands) in the periphery plays in the function of mature T cells remains unclear. Here, we elucidate a role for MHC class II molecules in T cell trafficking and antigen responsiveness in vivo. We find that naïve CD4 T cells deprived of MHC class II molecules demonstrate a progressive and profound defect in motility (measured by real-time two-photon imaging) and that these cells have a decreased ability to interact with limiting numbers of cognate antigen-bearing dendritic cells, but they do not demonstrate a defect in their responsiveness to direct stimulation with anti-CD3 monoclonal antibody.

CD4 T cell-dependent conditioning of dendritic cells to produce IL-12 results in CD8-mediated graft rejection and avoidance of tolerance.

Rejection of ectopic heart transplants expressing OVA requires OVA-specific CD4 and CD8 T cells. In the absence of CD4 T cells, OVA-specific CD8 T cells proliferate and migrate to the graft, but fail to develop cytolytic functions. With CD4 T cells present, clonal expansion of the CD8 T cells is only marginally increased but the cells now develop effector functions and mediate rapid graft rejection.