210 research outputs found
Intravitreal triamcinolone for intraocular inflammation and associated macular edema
Triamcinolone acetonide (TA) is a corticosteroid that has many uses in the treatment of ocular diseases because of its potent anti-inflammatory and anti-permeability actions. Intraocular inflammation broadly referred to as uveitis can result from several causes, including the immune system and after ophthalmic surgery. One of the most common reasons for vision loss with uveitis is macular edema. TA has been used for many years as an intravitreal injection for the treatment of ocular diseases. Several case control studies have been reported showing the efficacy of TA in the treatment of intraocular inflammation and associated macular edema caused by Behcet’s disease, Vogt-Koyanagi-Harada syndrome, sympathetic ophthalmia and white dot syndromes. It has also been shown efficacious in cases of pars planitis and idiopathic posterior uveitis. Some authors have reported its use in postoperative cystoid macular edema. Many of the studies on the use of TA in controlling intraocular inflammation and concomitant macular edema showed its effect to be transient in many patients requiring reinjection. Complications can arise from intravitreal injection of TA including elevated intraocular pressure and cataract. Rarely, it can be associated with infectious and non-infectious endophthalmitis. TA may be useful as an adjuvant in the treatment of uveitis and its associated macular edema, especially in patients resistant or intolerant to standard treatment
Use of triamcinolone during vitrectomy surgery to visualize membranes and vitreous
Triamcinolone is a corticosteroid that is used to treat many ophthalmic diseases. Recently, its use has been advocated to aid in visualization of transparent tissue in ophthalmic surgery. It can be used in anterior segment surgery to help manage vitreous loss during complicated cataract surgery. It has been used to visualize the posterior cortical vitreous during pars plana vitrectomy. In addition, it can be useful in the visualization and peeling of the internal limiting membrane. Triamcinolone has been advocated in surgical repair of proliferative vitreoretinopathy both for its visualizing properties and its anti-inflammatory properties. Overall, triamcinolone use in surgery is safe with low incidence of complications including elevated intraocular pressure, cataract and endophthalmitis
External dacryocystorhinostomy: A comparison of ultrasonic bone aspiration to high-speed drilling
Purpose: Piezosurgical tools utilize high-frequency ultrasonic oscillations to selectively cut mineralized bone and minimize damage to soft tissue and mucosa. The purpose of this study was to directly compare outcomes in external dacryocystorhinostomy (DCR) using a piezoelectric ultrasonic bone aspirator (UBA) versus a high-speed electric drill with a diamond burr.
Methods: A retrospective chart review was conducted on 145 consecutive patients who underwent external DCR by a single oculoplastic surgeon between 2012 and 2017. Collected data included baseline patient characteristics, presenting symptoms, operative details and complications, and postoperative symptoms.
Results: One hundred and seventy-three primary external DCRs performed on 145 patients were included in this study. In total, 61.3% of cases were performed with the UBA and 38.7% with the high-speed drill. Most patients were white (92.4%) and female (67.6%), with a mean age of 57.6 years (range 1-93). Surgical success was achieved in 94.3% of patients in the UBA group and 94.0% in the drill group, with no significant differences between the two arms (
Conclusion: The UBA offers comparable outcomes and complication rates to more conventional surgical tools for external DCR. Excellent outcomes, ease of adoption, and potential surgical time savings make the UBA an appealing option for both novice and experienced surgeons
Characterizing the Directionality of Gravitational Wave Emission from Matter Motions within Core-collapse Supernovae
We analyze the directional dependence of the gravitational wave (GW) emission
from 15 3D neutrino radiation hydrodynamic simulations of core-collapse
supernovae. We develop a new analytic technique to characterize the
distribution of GW emission over all angles. We use physics-informed toy models
to provide closed form expressions for the distribution of GW emission for
different CCSN phases. Using these toy models, we approximate the PNS dynamics
during multiple CCSN stages and obtain similar GW distributions to simulation
outputs. By applying this new technique throughout the supernova duration, we
construct a distribution of preferred directions of GW emission. Our findings
indicate CCSNe do not have a single `optimal' viewing angle along which the
strongest GWs can be detected. For nonrotating cases, this dominant viewing
angle drifts isotropically throughout the supernova, set by the dynamical
timescale of the protoneutron star. For rotating cases, during core bounce and
the following tens of ms, the strongest GW signal is observed along the
equator. During the accretion phase, comparable -- if not stronger -- GW
amplitudes are generated along the axis of rotation, which can be enhanced by
the low T/|W| instability. We show two dominant factors influencing the
directionality of GW emission are the degree of initial rotation and explosion
morphology. Lastly, looking forward, we note the sensitive interplay between GW
detector site and supernova orientation, along with its effect on detecting
individual polarization modes.Comment: 32 pages, 17 Figures, submitted to Ap
The nature of the dwarf population in Abell 868
We present the results of a study of the morphology of the dwarf galaxy
population in Abell 868, a rich, intermediate redshift (z=0.154) cluster which
has a galaxy luminosity function with a steep faint-end slope (alpha=-1.26 +/-
0.05). A statistical background subtraction method is employed to study the B-R
colour distribution of the cluster galaxies. This distribution suggests that
the galaxies contributing to the faint-end of the measured cluster LF can be
split into three populations: dIrrs with B-R<1.4; dEs with 1.4<B-R<2.5; and
contaminating background giant ellipticals (gEs) with B-R>2.5. The remvoal of
the contribution of the background gEs from the counts only marginally lessens
the faint-end slope (alpha=-1.22 +/- 0.16). However, the removal of the
contribution of the dIrrs from the counts produces a flat LF (alpha=-0.91 +/-
0.16). The dEs and the dIrrs have similar spatial distributions within the
cluster except that the dIrrs appear to be totally absent within a central
projected radius of about 0.2 Mpc (Ho=75 km/s /Mpc). The number density of both
dEs and dIrrs appear to fall off beyond a projected radius of about 0.35 Mpc.
We suggest that the dE and dIrr populations of A868 have been associated with
the cluster for similar timescales but that evolutionary processes such as
`galaxy harassment' tend to fade the dIrr galaxies while having much less
effect on the dE galaxies. The harassement would be expected to have the
greatest effect on dwarfs residing in the central parts of the cluster.Comment: 6 pages, 6 figures To be published in The Monthly Notices of the
Royal Astronomical Societ
Spectroscopy of Luminous Compact Blue Galaxies in Distant Clusters I. Spectroscopic Data
We used the DEIMOS spectrograph on the Keck II Telescope to obtain spectra of
galaxies in the fields of five distant, rich galaxy clusters over the redshift
range 0.5 < z < 0.9 in a search for luminous, compact, blue galaxies (LCBGs).
Unlike traditional studies of galaxy clusters, we preferentially targeted blue
cluster members identified via multi-band photometric pre-selection based on
imaging data from the WIYN telescope. Of the 1288 sources that we targeted, we
determined secure spectroscopic redshifts for 848 sources, yielding a total
success rate of 66%. Our redshift measurements are in good agreement with those
previously reported in the literature, except for 11 targets which we believe
were previously in error. Within our sample, we confirm the presence of 53
LCBGs in the five galaxy clusters. The clusters all stand out as distinct peaks
in the redshift distribution of LCBGs with the average number density of LCBGs
ranging from 1.65+-0.25 Mpc^-3 at z=0.55 to 3.13+-0.65 Mpc^-3 at z=0.8. The
number density of LCBGs in clustes exceeds the field desnity by a factor of
749+-116 at z=0.55; at z=0.8, the corresponding ratio is E=416+-95. At z=0.55,
this enhancement is well above that seen for blue galaxies or the overall
cluster population, indicating that LCBGs are preferentially triggered in
high-density environments at intermediate redshifts.Comment: 45 pages, 19 figures, accepted to ApJ. For Full resolution figure and
data tables, see http://www.salt.ac.za/~crawford/projects/deimos
GAMA: towards a physical understanding of galaxy formation
The Galaxy And Mass Assembly (GAMA) project is the latest in a tradition of
large galaxy redshift surveys, and is now underway on the 3.9m Anglo-Australian
Telescope at Siding Spring Observatory. GAMA is designed to map extragalactic
structures on scales of 1kpc - 1Mpc in complete detail to a redshift of z~0.2,
and to trace the distribution of luminous galaxies out to z~0.5. The principal
science aim is to test the standard hierarchical structure formation paradigm
of Cold Dark Matter (CDM) on scales of galaxy groups, pairs, discs, bulges and
bars. We will measure (1) the Dark Matter Halo Mass Function (as inferred from
galaxy group velocity dispersions); (2) baryonic processes, such as star
formation and galaxy formation efficiency (as derived from Galaxy Stellar Mass
Functions); and (3) the evolution of galaxy merger rates (via galaxy close
pairs and galaxy asymmetries). Additionally, GAMA will form the central part of
a new galaxy database, which aims to contain 275,000 galaxies with
multi-wavelength coverage from coordinated observations with the latest
international ground- and space-based facilities: GALEX, VST, VISTA, WISE,
HERSCHEL, GMRT and ASKAP. Together, these data will provide increased depth
(over 2 magnitudes), doubled spatial resolution (0.7"), and significantly
extended wavelength coverage (UV through Far-IR to radio) over the main SDSS
spectroscopic survey for five regions, each of around 50 deg^2. This database
will permit detailed investigations of the structural, chemical, and dynamical
properties of all galaxy types, across all environments, and over a 5 billion
year timeline.Comment: GAMA overview which appeared in the October 2009 issue of Astronomy &
Geophysics, ref: Astron.Geophys. 50 (2009) 5.1
A large population of ultra-compact dwarfs and bright intracluster globulars in the Fornax cluster
All the previously cataloged ultracompact dwarf (UCD) galaxies in the Fornax and Virgo clusters have 17.5 < b(J) < 20. Using the 2dF spectrograph on the Anglo-Australian Telescope, we have carried out a search for fainter UCDs in the Fornax Cluster. In the magnitude interval 19.5 < b(J) < 21.5, we have found 54 additional compact cluster members within a projected radius of 0 degrees.9 (320 kpc) of the cluster center, all of which meet our selection and observational criteria to be UCDs. These newly identified objects, however, overlap in luminosity and spatial distribution with objects classified as globular clusters (GCs) belonging to the central cluster galaxy NGC 1399; in fact, about half of the objects in our sample are included in recent catalogs of NGC 1399/Fornax GCs. The numbers, luminosity function, and spatial distributions of our compact object sample are consistent with being the bright tail of the Fornax cluster-wide GC population. Yet, our present larger sample of intergalactic compact objects forms a dynamically distinct population from both the NGC1399 GCs and the nucleated dwarf ellipticals in Fornax. This supports the interpretation that the UCDs, which populate the bright tail of the GC luminosity function, are, in some respects, a separate class of objects, at least to the extent that they have experienced a distinct dynamical history and origin, which differs from the bulk of the NGC1399 GCs. Correcting for our spectroscopic incompleteness, we estimate that there are similar to 105 +/- 13 of these brighter compact cluster objects down to b(J) < 21.5 in the central region of the Fornax, and hence these UCDs/globulars outnumber other galaxy types in this space. The differences in their dynamics and distribution compared to dwarf ellipticals (dEs) may be consistent with a threshing or tidal destruction origin, if they have come from a subpopulation of dE galaxies on initial orbits that rendered them susceptible to such processes
Exome sequencing identifies FANCM as a susceptibility gene for triple-negative breast cancer
Peer reviewe
Teprotumumab for Thyroid-Associated Ophthalmopathy
BACKGROUND:
Thyroid-associated ophthalmopathy, a condition commonly associated with Graves' disease, remains inadequately treated. Current medical therapies, which primarily consist of glucocorticoids, have limited efficacy and present safety concerns. Inhibition of the insulin-like growth factor I receptor (IGF-IR) is a new therapeutic strategy to attenuate the underlying autoimmune pathogenesis of ophthalmopathy.
METHODS:
We conducted a multicenter, double-masked, randomized, placebo-controlled trial to determine the efficacy and safety of teprotumumab, a human monoclonal antibody inhibitor of IGF-IR, in patients with active, moderate-to-severe ophthalmopathy. A total of 88 patients were randomly assigned to receive placebo or active drug administered intravenously once every 3 weeks for a total of eight infusions. The primary end point was the response in the study eye. This response was defined as a reduction of 2 points or more in the Clinical Activity Score (scores range from 0 to 7, with a score of ≥3 indicating active thyroid-associated ophthalmopathy) and a reduction of 2 mm or more in proptosis at week 24. Secondary end points, measured as continuous variables, included proptosis, the Clinical Activity Score, and results on the Graves' ophthalmopathy-specific quality-of-life questionnaire. Adverse events were assessed.
RESULTS:
In the intention-to-treat population, 29 of 42 patients who received teprotumumab (69%), as compared with 9 of 45 patients who received placebo (20%), had a response at week 24 (P<0.001). Therapeutic effects were rapid; at week 6, a total of 18 of 42 patients in the teprotumumab group (43%) and 2 of 45 patients in the placebo group (4%) had a response (P<0.001). Differences between the groups increased at subsequent time points. The only drug-related adverse event was hyperglycemia in patients with diabetes; this event was controlled by adjusting medication for diabetes.
CONCLUSIONS:
In patients with active ophthalmopathy, teprotumumab was more effective than placebo in reducing proptosis and the Clinical Activity Score. (Funded by River Vision Development and others; ClinicalTrials.gov number, NCT01868997 .)
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