Effect of intravitreal anti-VEGF on choroidal thickness in patients with diabetic macular edema using spectral domain OCT

ABSTRACT Purpose: To evaluate choroidal thickness (CT) using spectral domain optical coherence tomography (SD-OCT) imaging at baseline and 6 months after intravitreal anti-vascular endothelial growth factor (anti-VEGF) treatment in patients with diabetic macular edema (DME). Methods: A retrospective chart review was performed to identify patients with DME who underwent intravitreal injection of anti-VEGF (bevacizumab or ranibizumab) in a pro re nata (PRN) regimen. Subfoveal choroidal thickness was compared between values obtained at baseline and at 6-month follow-up visits. Results: Thirty-nine eyes (15 females, 24 males) from 39 patients were enrolled (mean age, 62.43 ± 8.7 years; range, 44-79 years). Twenty-three and 16 eyes were treated with ranibizumab and bevacizumab respectively. The mean number of anti-VEGF injections was 2.28 ± 1.27 (range, 1-5). Mean nasal, subfoveal, and temporal choroidal thickness (CT) measurements at baseline were 234.10 ± 8.63 µm, 246.89 ± 8.94 µm, and 238.12 ± 8.20 µm, respectively, and those at 6 months post-treatment were 210.46 ± 8.00 µm, 215.66 ± 8.29 µm, and 212.43 ± 8.14 µm, respectively. Significant differences in CT were observed between baseline and the 6-month follow-up at all measured points (p=0.0327). Conclusions: Over a 6-month period, the use of intravitreal anti-VEGF was associated with significant thinning of the choroid in patients with DME. The clinical significance of a thinner choroid in DME is currently unknown; however, it may contribute to long-term adverse effects on choroidal and retinal function, representing an area requiring future investigation

Evidence for Secretion of a Netrin-1-like Protein by Tetrahymena thermophila

Netrin-1 is a pleiotropic signaling molecule with targets in many mammalian cell types. Though first characterized as a chemotactic signal involved in neuronal guidance during development, netrin-1 has since been found to have a regulatory role in angiogenesis, and is also used as a biomarker in certain cancers. Tetrahymena thermophila are free-living protists that rely on chemotactic signals to find food, as well as to escape predators. Chemoattractants cause the cells to swim faster in the forward direction, while chemorepellents cause ciliary reversal, resulting in movement of the cell away from the noxious stimulus. We have previously found that netrin-1 is a chemorepellent in T. thermophila. More recently, we have detected netrin-1 by ELISA in both whole cell extract and secreted protein samples obtained from T. thermophila. In addition, we have immunolocalized netrin-1 staining to the cytosol of T. thermophila using an anti-netrin-1 antibody. We are currently running Western blots to determine the molecular weight of this protein and compare it to its vertebrate counterparts. Further experimentation is needed to determine the physiological role of this protein in T. thermophila

Searching for Exoplanets Using a Microresonator Astrocomb

Detection of weak radial velocity shifts of host stars induced by orbiting planets is an important technique for discovering and characterizing planets beyond our solar system. Optical frequency combs enable calibration of stellar radial velocity shifts at levels required for detection of Earth analogs. A new chip-based device, the Kerr soliton microcomb, has properties ideal for ubiquitous application outside the lab and even in future space-borne instruments. Moreover, microcomb spectra are ideally suited for astronomical spectrograph calibration and eliminate filtering steps required by conventional mode-locked-laser frequency combs. Here, for the calibration of astronomical spectrographs, we demonstrate an atomic/molecular line-referenced, near-infrared soliton microcomb. Efforts to search for the known exoplanet HD 187123b were conducted at the Keck-II telescope as a first in-the-field demonstration of microcombs

The WiggleZ Dark Energy Survey: the growth rate of cosmic structure since redshift z=0.9

We present precise measurements of the growth rate of cosmic structure for the redshift range 0.1 < z < 0.9, using redshift-space distortions in the galaxy power spectrum of the WiggleZ Dark Energy Survey. Our results, which have a precision of around 10% in four independent redshift bins, are well-fit by a flat LCDM cosmological model with matter density parameter Omega_m = 0.27. Our analysis hence indicates that this model provides a self-consistent description of the growth of cosmic structure through large-scale perturbations and the homogeneous cosmic expansion mapped by supernovae and baryon acoustic oscillations. We achieve robust results by systematically comparing our data with several different models of the quasi-linear growth of structure including empirical models, fitting formulae calibrated to N-body simulations, and perturbation theory techniques. We extract the first measurements of the power spectrum of the velocity divergence field, P_vv(k), as a function of redshift (under the assumption that P_gv(k) = -sqrt[P_gg(k) P_vv(k)] where g is the galaxy overdensity field), and demonstrate that the WiggleZ galaxy-mass cross-correlation is consistent with a deterministic (rather than stochastic) scale-independent bias model for WiggleZ galaxies for scales k < 0.3 h/Mpc. Measurements of the cosmic growth rate from the WiggleZ Survey and other current and future observations offer a powerful test of the physical nature of dark energy that is complementary to distance-redshift measures such as supernovae and baryon acoustic oscillations.Comment: 17 pages, 11 figures, accepted for publication by MNRA

The WiggleZ Dark Energy Survey: Survey Design and First Data Release

The WiggleZ Dark Energy Survey is a survey of 240,000 emission line galaxies in the distant universe, measured with the AAOmega spectrograph on the 3.9-m Anglo-Australian Telescope (AAT). The target galaxies are selected using ultraviolet photometry from the GALEX satellite, with a flux limit of NUV<22.8 mag. The redshift range containing 90% of the galaxies is 0.2<z<1.0. The primary aim of the survey is to precisely measure the scale of baryon acoustic oscillations (BAO) imprinted on the spatial distribution of these galaxies at look-back times of 4-8 Gyrs. Detailed forecasts indicate the survey will measure the BAO scale to better than 2% and the tangential and radial acoustic wave scales to approximately 3% and 5%, respectively. This paper provides a detailed description of the survey and its design, as well as the spectroscopic observations, data reduction, and redshift measurement techniques employed. It also presents an analysis of the properties of the target galaxies, including emission line diagnostics which show that they are mostly extreme starburst galaxies, and Hubble Space Telescope images, which show they contain a high fraction of interacting or distorted systems. In conjunction with this paper, we make a public data release of data for the first 100,000 galaxies measured for the project.Comment: Accepted by MNRAS; this has some figures in low resolution format. Full resolution PDF version (7MB) available at http://www.physics.uq.edu.au/people/mjd/pub/wigglez1.pdf The WiggleZ home page is at http://wigglez.swin.edu.au

Lateralization of mesial temporal lobe epilepsy with chronic ambulatory electrocorticography

OBJECTIVE: Patients with suspected mesial temporal lobe (MTL) epilepsy typically undergo inpatient video-electroencephalography (EEG) monitoring with scalp and/or intracranial electrodes for 1 to 2 weeks to localize and lateralize the seizure focus or foci. Chronic ambulatory electrocorticography (ECoG) in patients with MTL epilepsy may provide additional information about seizure lateralization. This analysis describes data obtained from chronic ambulatory ECoG in patients with suspected bilateral MTL epilepsy in order to assess the time required to determine the seizure lateralization and whether this information could influence treatment decisions. METHODS: Ambulatory ECoG was reviewed in patients with suspected bilateral MTL epilepsy who were among a larger cohort with intractable epilepsy participating in a randomized controlled trial of responsive neurostimulation. Subjects were implanted with bilateral MTL leads and a cranially implanted neurostimulator programmed to detect abnormal interictal and ictal ECoG activity. ECoG data stored by the neurostimulator were reviewed to determine the lateralization of electrographic seizures and the interval of time until independent bilateral MTL electrographic seizures were recorded. RESULTS: Eighty-two subjects were implanted with bilateral MTL leads and followed for 4.7 years on average (median 4.9 years). Independent bilateral MTL electrographic seizures were recorded in 84%. The average time to record bilateral electrographic seizures in the ambulatory setting was 41.6 days (median 13 days, range 0-376 days). Sixteen percent had only unilateral electrographic seizures after an average of 4.6 years of recording. SIGNIFICANCE: About one third of the subjects implanted with bilateral MTL electrodes required >1 month of chronic ambulatory ECoG before the first contralateral MTL electrographic seizure was recorded. Some patients with suspected bilateral MTL seizures had only unilateral electrographic seizures. Chronic ambulatory ECoG in patients with suspected bilateral MTL seizures provides data in a naturalistic setting, may complement data from inpatient video-EEG monitoring, and can contribute to treatment decisions

Adolescent/Youth Reproductive Mobile Access and Delivery Initiative for Love and Life Outcomes (ARMADILLO) Study: formative protocol for mHealth platform development and piloting

BACKGROUND: There is a high unmet need for sexual and reproductive health (SRH) information and services among youth (ages 15-24) worldwide (MacQuarrie KLD. Unmet Need for Family Planning among Young Women: Levels and Trends 2014). With the proliferation of mobile technology, and its popularity with this age group, mobile phones offer a novel and accessible platform for a discreet, on-demand service providing SRH information. The Adolescent/Youth Reproductive Mobile Access and Delivery Initiative for Love and Life Outcomes (ARMADILLO) formative study will inform the development of an intervention, which will use the popular channel of SMS (text messages) to deliver SRH information on-demand to youth. METHODS/DESIGN: Following the development of potential SMS message content in partnership with SRH technical experts and youth, formative research activities will take place over two phases. Phase 1 will use focus group discussions (FGDs) with youth and parents/caregivers to develop and test the appropriateness and acceptability of the SMS messages. Phase 2 will consist of ‘peer piloting’, where youth participants will complete an SRH outcome-focused pretest, be introduced to the system and then have three weeks to interact with the system and share it with friends. Participants will then return to complete the SRH post-test and participate in an in-depth interview about their own and their peers’ opinions and experiences using ARMADILLO. DISCUSSION: The ARMADILLO formative stage will culminate in the finalization of country-specific ARMADILLO messaging. Reach and impact of ARMADILLO will be measured at later stages. We anticipate that the complete ARMADILLO platform will be scalable, with the potential for national-level adoption

Image Processing Algorithms for Digital Mammography: A Pictorial Essay

Digital mammography systems allow manipulation of fine differences in image contrast by means of image processing algorithms. Different display algorithms have advantages and disadvantages for the specific tasks required in breast imaging—diagnosis and screening. Manual intensity windowing can produce digital mammograms very similar to standard screen-film mammograms but is limited by its operator dependence. Histogram-based intensity windowing improves the conspicuity of the lesion edge, but there is loss of detail outside the dense parts of the image. Mixture-model intensity windowing enhances the visibility of lesion borders against the fatty background, but the mixed parenchymal densities abutting the lesion may be lost. Contrast-limited adaptive histogram equalization can also provide subtle edge information but might degrade performance in the screening setting by enhancing the visibility of nuisance information. Unsharp masking enhances the sharpness of the borders of mass lesions, but this algorithm may make even an indistinct mass appear more circumscribed. Peripheral equalization displays lesion details well and preserves the peripheral information in the surrounding breast, but there may be flattening of image contrast in the nonperipheral portions of the image. Trex processing allows visualization of both lesion detail and breast edge information but reduces image contrast