Comparison of Framingham risk score and chest-CT identified coronary artery calcification in breast cancer patients to predict cardiovascular events.

Background: In breast cancer patients, coincidental detection of CAC at chest CT may be important in determining cardiovascular (CV) outcomes and facilitate CV disease primary prevention strategies.

Methods: 408 consecutive breast cancer patients referred to cardiac oncology clinic were included in the study. 256 patients without a prior history of coronary artery disease had undergone a chest CT.

Reporting of coronary artery calcification on chest CT studies in breast cancer patients at high risk of cancer therapy related cardiac events.

Background: The identification of coronary artery calcification (CAC) detected coincidentally on chest CT exams could assist in cardiovascular risk assessment but may not be reported consistently on clinical studies. Cardiovascular risk factor stratification is important to predict short term cardiac events during cancer therapy and long term cardiac event free survival in cancer patients. We sought to determine the prevalence of CAC and clinical reporting rates in a cohort of cancer patients at high risk of cancer therapy related cardiac events.

Multifluorophore localization as a percolation problem: limits to density and precision.

We show that the maximum desirable density of activated fluorophores in a superresolution experiment can be determined by treating the overlapping point spread functions as a problem in percolation theory. We derive a bound on the density of activated fluorophores, taking into account the desired localization accuracy and precision, as well as the number of photons emitted. Our bound on density is close to that reported in experimental work, suggesting that further increases in the density of imaged fluorophores will come at the expense of localization accuracy and precision.

Lengthening strategies for Peyronie's disease.

Loss of penile length is a common complaint of men with Peyronie's disease (PD), both before and after corrective intervention, which has a significant negative effect on patient quality of life. We sought to identify and describe the methods by which penile length can be preserved or increased. We conducted an extensive, systematic literature review, based on a search of the PUBMED database for articles published between 1990 and 2015.

Fluorophore localization algorithms for super-resolution microscopy.

Super-resolution localization microscopy methods provide powerful new capabilities for probing biology at the nanometer scale via fluorescence. These methods rely on two key innovations: switchable fluorophores (which blink on and off and can be sequentially imaged) and powerful localization algorithms (which estimate the positions of the fluorophores in the images). These techniques have spurred a flurry of innovation in algorithm development over the last several years.

Generalization of the optical theorem for light scattering from a particle at a planar interface.

The optical theorem provides a powerful tool for calculating the extinction cross section of a particle from a solution to Maxwell's equations, relating the cross section to the scattering amplitude in the forward direction. The theorem has been generalized by a number of other workers to consider a particle near an interface between media with different refractive indices. Here we present a derivation of the generalized optical theorem that is valid for a particle embedded in the interface, as well as an incident beam undergoing total internal reflection.

Comparison of 3 upper tract anticarcinogenic agent delivery techniques in an ex vivo porcine model.

Objective: To evaluate the degree of urothelial exposure using 3 upper tract delivery techniques in an ex vivo porcine model, to determine the optimal modality to locally deliver topical anticarcinogenic agents in patients with upper tract urothelial carcinoma.

Materials And Methods: An indigo carmine solution was infused into en bloc porcine urinary tracts to test the 3 techniques: antegrade infusion via nephrostomy tube, reflux via indwelling double-pigtail stent, and retrograde administration via a 5F open-ended ureteral catheter. Nine renal units (3 per delivery method) were used.

Fast maximum likelihood algorithm for localization of fluorescent molecules.

A common task in microscopy is to fit an image of a fluorescent probe to a point spread function (PSF) in order to estimate the position of the probe. The PSF is often approximated as a Gaussian for mathematical simplicity. We show that the separable property of the Gaussian PSF enables a reduction of computational time from O(L2) to O(L), where L is the width (in pixels) of the image.

Model of bleaching and acquisition for superresolution microscopy controlled by a single wavelength.

We consider acquisition schemes that maximize the fraction of images that contain only a single activated molecule (as opposed to multiple activated molecules) in superresolution localization microscopy of fluorescent probes. During a superresolution localization microscopy experiment, irreversible photobleaching destroys fluorescent molecules, limiting the ability to monitor the dynamics of long-lived processes. Here we consider experiments controlled by a single wavelength, so that the bleaching and activation rates are coupled variables.

Optimal acquisition scheme for subwavelength localization microscopy of bleachable fluorophores.

We consider the problem of optimizing superresolution microscopy with photoswitchable molecules that irreversibly photobleach. Using variational methods, we show that the number of single-molecule images is maximized in a simple scheme with a constant number of activated fluorophores per cycle. For high-speed acquisition, deviations from the optimal scheme do reduce the information collected but fortuitously also reduce certain types of errors, making the scheme very robust.

Topology of the heterogeneous nature of the extracellular matrix on stochastic modeling of tumor-induced angiogenesis.

We have modeled tumor-induced angiogenesis; our model includes the phenomena of the migratory response of endothelial cells (ECs) to tumor angiogenic factors, and the interaction of ECs with the extracellular matrix (ECM). ECs switch between growth, differentiation, motility, or apoptotic behavior in response to the local topology and composition of the ECM. Assuming the ECM medium as a statistically inhomogeneous medium (some area support sprout growth, some not), we show that the ECM can be a natural barrier to angiogenesis.

Thin films of oriented collagen fibrils for cell motility studies.

Collagen films with oriented fibrils mimic tissues that have been remodeled by fibroblasts, which naturally tend to orient collagen fibrils in vivo. We have prepared thin films of ordered fibrils of collagen I, a major component of the extracellular matrix. The films were prepared by modifying a technique previously used to produce collagen I films for studies of cell morphology and intracellular signaling.

Stochastic modeling of tumor induced angiogenesis in a heterogeneous medium, the extracellular matrix.

Angiogenesis, the formation of blood vessels, is a process whereby capillary sprout are formed in response to external stimuli. We model the tumor induced angiogenesis on keys events such of migratory response of endothelial cells to tumor angiogenic factors and the local cell interaction with the extracellular matrix (ECM). We consider the ECM medium as a statistically inhomogeneous two-phase random medium.

Delocalization of classical waves in highly anisotropic random media.

We discuss localization phenomena in multilayer films doped with scattering particles. If the films exhibit a particular type of transmission resonance then above a critical frequency waves in the sample can decay as a power law rather than exponentially. This phenomenon is independent of the scattering strength of the particles, in stark contrast to previous work.

Mutation analysis of 24 known cancer genes in the NCI-60 cell line set.

The panel of 60 human cancer cell lines (the NCI-60) assembled by the National Cancer Institute for anticancer drug discovery is a widely used resource. The NCI-60 has been characterized pharmacologically and at the molecular level more extensively than any other set of cell lines. However, no systematic mutation analysis of genes causally implicated in oncogenesis has been reported.

Enhancing diffraction-limited images using properties of the point spread function.

We propose an algorithm to enhance diffraction-limited images based on pixel-to-pixel correlations introduced by the finite width of the Point Spread Function (PSF). We simulate diffraction-limited images of point sources by convolving the PSF of a diffraction-limited lens with simulated images, and enhance the blurred images with our algorithm. Our algorithm reduces the PSF width, increases the contrast, and reveals structure on a length scale half of that resolvable in the unenhanced image.