117 research outputs found

    Clinical Outcomes in Patients with Heterogeneous Vancomycin-Intermediate Staphylococcus aureus Bloodstream Infection

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    The prevalence of heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA) infections varies in the literature, a problem complicated by the lack of routine screening procedures; however, limited data suggest that hVISA has been associated with persistent bloodstream infections (BSI) and vancomycin failure, yet these studies have been confounded by design issues. We conducted this study to compare the characteristics of patients with BSI caused by hVISA with those with vancomycin-susceptible Staphylococcus aureus (VSSA) treated with vancomycin. This retrospective, multicenter matched (1:1) cohort study compared the clinical characteristics and outcomes of hVISA and VSSA. Patients with hVISA methicillin-resistant Staphylococcus aureus (MRSA) BSI from 2004 to 2012 were matched to VSSA-MRSA BSI patients. The primary outcome was failure of vancomycin treatment, defined as a composite of persistent bacteremia (≥7 days), persistent signs and symptoms, change of MRSA antibiotic, recurrent BSI, or MRSA-related mortality. We identified 122 matched cases. The overall vancomycin failure rate was 57% (82% hVISA versus 33% VSSA; P \u3c 0.001). The individual components of failure in hVISA versus VSSA were persistent bacteremia, 59% versus 21% (P \u3c 0.001); change in MRSA therapy, 54% versus 25% (P = 0.001); MRSA-related mortality, 21% versus 10% (P = 0.081); and recurrence of BSI, 26% versus 2% (P \u3c 0.001). Using logistic regression analysis and adjusting for covariates, hVISA (adjusted odds ratio [aOR], 11.1; 95% confidence interval [CI], 4.3 to 28.7) and intensive care unit (ICU) admission (aOR, 4.5; 95% CI, 1.8 to 11.6) were still independently associated with vancomycin failure. Relative to VSSA BSI, patients with hVISA were more likely to experience failure of vancomycin treatment, including persistent bacteremia and recurrence. Our results indicate that hVISA was responsible for considerable morbidity

    Tracking RPE transplants labeled by retroviral gene transfer with green fluorescent protein

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    PURPOSE. To determine whether human retinal pigment epithelium (RPE) can be modified by retroviral-mediated gene transfer and to monitor the human RPE cells in the subretinal space of living rabbits with scanning laser ophthalmoscopy (SLO). METHODS. Cultured human fetal retinal pigment epithelium (HFRPE) was exposed to green fluorescent protein (GFP)-transducing retroviral vectors, Moloney murine leukemia virus, and lentivirus. The cultured cells were followed by fluorescence microscopy. Suspensions of GFP-expressing HFRPE were transplanted into the subretinal space of pigmented rabbits, and the transplant sites were examined by SLO for fluorescence, including fluorescein and indocyanine green angiography. The rabbits were euthanatized at different times after transplantation, and the retinas were studied histologically. RESULTS. Retroviral gene transfer can introduce a foreign gene such as GFP into cultured HFRPE. Gene expression is maintained in cultured RPE for at least 3 months. The lentiviral vector traduced both nondividing and dividing cells; the Moloney vector only transduced the latter. GFPexpressing cells can be followed in the living retina. Their changes reflect the rejection response followed histologically. CONCLUSIONS. Cultured HFRPE could be transduced to express GFP for long periods of time by retroviral gene transfer. GFP allowed retinal transplants and gene expression to be monitored in vivo. These results provide a model for potential ex vivo gene therapy in the subretinal space. (Invest Ophthalmol Vis Sci. 1999;40:2141-2146 T he green fluorescent protein (GFP) gene has been derived from the bioluminescent jelly fish, Aequorin victoria. This protein fluoresces green light when excited by blue or ultraviolet light. The cloning of this gene and the demonstration that it can be expressed in other organisms provides a useful way to select and follow cells exhibiting specific gene expression, [1][2][3] especially in a transparent structure such as the eye. 4 We have used replication-deficient retroviruses to transduce cultured human fetal retinal pigment epithelium (HFRPE) with the gene encoding GFP. We followed the expression of this protein in vitro by fluorescence microscopy and in vivo after transplantation to the subretinal space of rabbits by scanning laser ophthalmoscopy (SLO). We demonstrated that retroviral transduction is effective, stable, and long-lasting in vitro. It allows transplanted RPE to be monitored in the subretinal space and provides a noninvasive indicator of the time course of rejection. An abstract on some of this research has been published. 5 METHODS Culturing of RPE Donor tissue was obtained from human fetal eyes, 16 to 20 weeks of gestational age. Informed consent was obtained for the use of this tissue before abortion and institutional approval was granted through an agreement between Albert Einstein College of Medicine, the source of the tissue, and Columbia University. The eye bulbs were washed externally with 70% alcohol and then with phosphate-buffered saline (PBS). The eyes were put into our standard RPE culture medium, Dulbecco's modified Eagle's medium with 4.5 g/l glucose supplemented with 20% fetal calf serum (Hyclone, Logan, Utah), 2 mM L-glutamine and penicillin (50 unit/ml)/streptomycin (50 mg/ml) (Gibco, Grand Island, NY). The anterior segment with lens, vitreous, and neural retina was removed. The posterior segment was sliced into quadrants, and RPE patches were separated gently from Bruch's membrane and choroid, using fine forceps and microscopic viewing. A distinct cleavage plane is identifiable between the taut monolayer patch of RPE and the adjacent choroid so that an isolated sheet of RPE can be pulled off. Each sheet was placed in a separate culture plate. The edges of the sheet were pressed onto the surface of the plate with the tip of a 26-gauge needle. The cultures were maintained at 37°C in an incubator with a humidified atmosphere of 95% air/5% CO 2 , fed every 3 to 4 days, and examined almost daily. To obtain cell suspensions, we washed the cells with PBS three times and exposed them to 2.5% trypsin in Hank's solution with EDTA without Ca and Mg (Gibco) for 10 minutes at 37°C. The monolayer was triturated into single cells or clusters of cells by repeated pipetting. The concentration of cells in a suspension was determined with a hemocytometer. The cells were either used for transplantation or subcultured. Preparation of Virus Stocks For the Moloney vector a DNA construct was generated consisting of the humanized red-shifted GFP (EGFP) under the translational control of an Internal Ribosome Entry Site from the encephalomyocarditis virus (EMCV-IRES), flanked by long terminal repeat (LTR) of Moloney murine leukemia virus (MoMLV). These viral sequences include the two LTRs, and the two sites for initiation of viral DNA synthesis (the primer binding site for initiation of minus-strand DNA synthesis and the polypurine tract for initiation of plus-strand synthesis). They also include the RNA packaging signal, termed the Psi region, near the 5Ј end of the genome. The construct was then introduced into AM 12 packaging cells that express the viral proteins required for the assembly of a virion particle. The viral RNA was transcribed from a transfected plasmid and selectively packaged into viral particles produced by the packaging cells. The virions were collected from the culture medium, purified, and concentrated as needed. To transduce the gene to RPE, the virus was applied directly to the target cells. Typical titers were 10 5 to 10 6 infectious units/ml. For the lentiviral vector, human immunodeficiency virus (HIV)-based preparations were generated by cotransfection of human kidney-derived 293T cells by three plasmids using the CaPO 4 method. 6 The packaging construct contained the cytomegalovirus promoter and the insulin polyadenylation signal to express all the viral proteins in trans, except the envelope and Vpu. 6 The second plasmid provided a vector with all the cis-acting elements that allow transfer and integration into the target cell. In this transducing vector, an expression cassette with the Rev responsive element (RRE) and the cytomegalovirus promoter are used to direct the expression of GFP. 6 The third plasmid provides the envelope protein from the vesicular stomatitis virus glycoprotein to enhance the viral stability and the range of possible target cells. 6 The titer of the HIV vector was determined by a fluorescent activated cell sorter (FACStar plus; Becton Dickinson, Mountain View, CA) scanning GFPtransduced cells. The lentiviral titers were determined by infection of 293 cells seeded in 6-well plates at 1 ϫ 10 5 cells per well the day before infection with serial dilution of concentrated viral stock in the presence of 8 g/ml of polybrene (Aldrich, Milwaukee, WI). After overnight incubation, the cell culture medium was changed, and the cells were incubated further for 2 days. GFP fluorescent cells were identified by fluorescent microscopy and/or the FACS. Typical titers were 10 8 to 10 9 infectious units/ml. In Vitro Transfection For viral transduction, primary cultures were dissociated into cell suspensions and subcultured in 6-well plates containing approximately 10 5 cells/well. This promotes cell division and augments the total number of cells available. After 24 hours in standard RPE culture medium, the medium was replaced with the viral solution, consisting of Hepes buffer with 20% fetal calf serum, 2 mM L-glutamine, 8 g/ml polybrene, and a viral titer of 10 5 to 10 7 infectious units/ml before concentration. This solution was replaced with fresh viral solution every 6 hours for 48 hours. After 48 hours, this solution was replaced with standard RPE medium, and the cultures were allowed to reach confluency, examined by fluorescence microscopy, and used for transplantation. For comparing viral transduction of stationary versus dividing cells, the virus was introduced directly into the primary culture containing the original patch of heavily pigmented cells, surrounded by an expanding population of dividing cells, the size of which depended on the age of the culture. To determine the fraction of cells expressing GFP, the number of GFP fluorescent cells and the total number of cells were counted within defined areas, 0.4 ϫ 0.8 mm, in the culture plate. All cells that showed green fluorescence were considered to be expressing GFP. We examined cells in the same areas in three different parts of each culture plate, the patch that contained stationary pigmented cells only, the edge of the patch where cells were migrating and entering into cell division, and the growing margin of the culture, which contained many fewer pigmented, dividing cells. We measured these same areas repeatedly in 15 different cultures, weekly for 3 weeks; 5 cultures were measured for 6 weeks, and 1 culture for 3 months. In one case, we dissociated a primary culture that we had examined for 3 months and replated the cells to follow GFP fluorescence after repeated cell division. Transplantation Thirty adult pigmented rabbits received subretinal transplants placed within small bleb detachments just below the myelinated region of the optic nerve. Bleb detachments also were formed in two rabbits with saline alone. Each animal was anesthetized with sodium pentobarbital (25 mg/kg, intramuscularly) and xylazine (10 mg/kg, intramuscularly). The pupil was dilated with 2% cyclopentolate and 2.5% neosynephrine. A lid speculum was used to keep the eye open and occasionally a canthotomy also was performed. A conjunctival flap was formed at the limbal region, and a sclerotomy made approximately 3 mm behind the limbus. A glass pipette with a tip diameter of 80 to 100 m, connected to a 1-ml syringe and filled with balanced salt solution (BSS) was introduced into the vitreal cavity. Using a corneal contact lens and a surgical microscope the pipette was directed to the retinal surface. At the surface of the retina a jet stream of BSS was slowly injected through the neural retina to produce a small bleb detachment. A second similar pipette was used to suck up a pellet of a concentrated solution of GFP-expressing HFRPE cells from the bottom of an Eppendorf tube. The cell suspension was obtained by rinsing a culture three times with PBS and then dissociating the cells with 0.05% trypsin for 5 minutes at 37°C. The cells were washed with PBS and centrifuged. The pellet was resuspended in 0.5 ml BSS, put into an Eppendorf tube, centrifuged at 1000 rpm for 2 minutes, and stored at 4°C. The cells were used within 2 hours of preparation. Approximately 10 l of cell suspension containing approximately 10 5 cells was introduced into the bleb detachment, either through the same retinotomy or through a second one; the latter method was preferable because it minimized any reflux of transplant cells into the vitreous. A small air bubble separated the suspension from the BSS solution in the pipette. The bubble also was introduced into the bleb detachment to prevent efflux of the transplant cells into the vitreous. The air bubble disappeared in 24 hours. After the pipette was removed, the sclera and conjunctiva were sutured with 9-0 nylon. Reports IOVS, August 1999, Vol. 40, No. 9 Downloaded from iovs.arvojournals.org on 06/30/2019 Retinal Examination Rabbits were examined 1 day after surgery, weekly for 8 weeks, and monthly thereafter by indirect ophthalmoscopy, SLO (Rodenstock, Munich, Germany) and sometimes by contact lens biomicroscopy. The SLO provided infrared (780 nmoles), He-Neon red (633 nmoles), argon green (514 nmoles), and blue (488 nmoles) illumination. We examined retinal fluorescence with argon blue illumination and a fluorescein barrier filter. We graded the fluorescence using a scale of 0 to 4 (0, no fluorescence,; 1, just detectable; 2, distinct; 3, strong; 4, very strong). Fluorescein and indocyanine green (ICG) angiography were performed simultaneously with an SLO double-detection system that was able to detect fluorescein and ICG simultaneously. Angiography was performed August 1999, Vol. 40, No. 9 Reports IOVS, weekly for 2 to 3 weeks and monthly thereafter. The dyes were injected into an ear vein in one bolus containing 0.2 ml fluorescein (100 mg/ml) and 0.7 ml ICG (4.2 mg/ml). Histology After the rabbit was euthanatized, the eyes were enucleated, punctured with a 20 gauge needle at several places near the limbus to facilitate diffusion, and immersed in a solution of either 3% glutaraldehyde or 4% paraformaldehyde in PBS at pH 7.2 for 24 to 48 hours at 4°C. The eyes then were washed with PBS and dissected with the aid of a microscope. The transplant site was located, examined, and cut out with its orientation marked so that the site could be reached with minimal sectioning. For Epon embedding, glutaraldehyde-fixed segments were postfixed with 1% osmic acid and dehydrated with ethanol. Sections were cut semi-serially and examined by light microscopy; selected areas were examined by electron microscopy. For cryosectioning paraformaldehyde-fixed segments were immersed in OCT compound (Miles, Elkhart, IN) and frozen by dry ice. Cryosectioning was performed on a Leica 1850 cryotome (Leica Instruments, Nusslach, Germany). Sections were mounted on gelatinized glass slides with fluoromount-G. GFP polyclonal antibody (diluted 1:100; Clontech Laboratories, Palo Alto, CA) was used for immunocytochemistry. Cultured RPE cells not exposed to the virus were used as a negative control. RESULTS GFP fluorescence was detectable in cultured HFRPE within 5 days after being exposed to the retrovirus. The MoMLV only transduced dividing cells that occurred along the edge of patch cultures spreading out centrifugally over the culture plate. 7 The lentivirus transduced both stationary and dividing cells

    The Eighth Data Release of the Sloan Digital Sky Survey: First Data from SDSS-III

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    The Sloan Digital Sky Survey (SDSS) started a new phase in August 2008, with new instrumentation and new surveys focused on Galactic structure and chemical evolution, measurements of the baryon oscillation feature in the clustering of galaxies and the quasar Ly alpha forest, and a radial velocity search for planets around ~8000 stars. This paper describes the first data release of SDSS-III (and the eighth counting from the beginning of the SDSS). The release includes five-band imaging of roughly 5200 deg^2 in the Southern Galactic Cap, bringing the total footprint of the SDSS imaging to 14,555 deg^2, or over a third of the Celestial Sphere. All the imaging data have been reprocessed with an improved sky-subtraction algorithm and a final, self-consistent photometric recalibration and flat-field determination. This release also includes all data from the second phase of the Sloan Extension for Galactic Understanding and Evolution (SEGUE-2), consisting of spectroscopy of approximately 118,000 stars at both high and low Galactic latitudes. All the more than half a million stellar spectra obtained with the SDSS spectrograph have been reprocessed through an improved stellar parameters pipeline, which has better determination of metallicity for high metallicity stars.Comment: Astrophysical Journal Supplements, in press (minor updates from submitted version

    The Ninth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-III Baryon Oscillation Spectroscopic Survey

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    The Sloan Digital Sky Survey III (SDSS-III) presents the first spectroscopic data from the Baryon Oscillation Spectroscopic Survey (BOSS). This ninth data release (DR9) of the SDSS project includes 535,995 new galaxy spectra (median z=0.52), 102,100 new quasar spectra (median z=2.32), and 90,897 new stellar spectra, along with the data presented in previous data releases. These spectra were obtained with the new BOSS spectrograph and were taken between 2009 December and 2011 July. In addition, the stellar parameters pipeline, which determines radial velocities, surface temperatures, surface gravities, and metallicities of stars, has been updated and refined with improvements in temperature estimates for stars with T_eff<5000 K and in metallicity estimates for stars with [Fe/H]>-0.5. DR9 includes new stellar parameters for all stars presented in DR8, including stars from SDSS-I and II, as well as those observed as part of the SDSS-III Sloan Extension for Galactic Understanding and Exploration-2 (SEGUE-2). The astrometry error introduced in the DR8 imaging catalogs has been corrected in the DR9 data products. The next data release for SDSS-III will be in Summer 2013, which will present the first data from the Apache Point Observatory Galactic Evolution Experiment (APOGEE) along with another year of data from BOSS, followed by the final SDSS-III data release in December 2014.Comment: 9 figures; 2 tables. Submitted to ApJS. DR9 is available at http://www.sdss3.org/dr

    The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment

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    The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since July 2014. This paper describes the second data release from this phase, and the fourteenth from SDSS overall (making this, Data Release Fourteen or DR14). This release makes public data taken by SDSS-IV in its first two years of operation (July 2014-2016). Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey (eBOSS); the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data driven machine learning algorithm known as "The Cannon"; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS website (www.sdss.org) has been updated for this release, and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020, and will be followed by SDSS-V.Comment: SDSS-IV collaboration alphabetical author data release paper. DR14 happened on 31st July 2017. 19 pages, 5 figures. Accepted by ApJS on 28th Nov 2017 (this is the "post-print" and "post-proofs" version; minor corrections only from v1, and most of errors found in proofs corrected

    Reduced expression of p27 is a novel mechanism of docetaxel resistance in breast cancer cells

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    INTRODUCTION: Docetaxel is one of the most effective chemotherapeutic agents in the treatment of breast cancer. Breast cancers can have an inherent or acquired resistance to docetaxel but the causes of this resistance remain unclear. However, apoptosis and cell cycle regulation are key mechanisms by which most chemotherapeutic agents exert their cytotoxic effects. METHODS: We created two docetaxel-resistant human breast cancer cell lines (MCF-7 and MDA-MB-231) and performed cDNA microarray analysis to identify candidate genes associated with docetaxel resistance. Gene expression changes were validated at the RNA and protein levels by reverse transcription PCR and western analysis, respectively. RESULTS: Gene expression cDNA microarray analysis demonstrated reduced p27 expression in docetaxel-resistant breast cancer cells. Although p27 mRNA expression was found to be reduced only in MCF-7 docetaxel-resistant sublines (2.47-fold), reduced expression of p27 protein was noted in both MCF-7 and MDA-MB-231 docetaxel-resistant breast cancer cells (2.83-fold and 3.80-fold, respectively). CONCLUSIONS: This study demonstrates that reduced expression of p27 is associated with acquired resistance to docetaxel in breast cancer cells. An understanding of the genes that are involved in resistance to chemotherapy may allow further development in modulating drug resistance, and may permit selection of those patients who are most likely to benefit from such therapies

    Comparison of the Safety and Pharmacokinetics of ST-246® after IV Infusion or Oral Administration in Mice, Rabbits and Monkeys

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    ST-246® is an antiviral, orally bioavailable small molecule in clinical development for treatment of orthopoxvirus infections. An intravenous (IV) formulation may be required for some hospitalized patients who are unable to take oral medication. An IV formulation has been evaluated in three species previously used in evaluation of both efficacy and toxicology of the oral formulation. plasma concentrations. These effects were eliminated using slower IV infusions. associated toxicity. Shorter infusions at higher doses in NHP resulted in decreased clearance, suggesting saturated distribution or elimination. Elimination half-lives in all species were similar between oral and IV administration. The administration of ST-246 was well tolerated as a slow IV infusion

    Safety of procuring research tissue during a clinically indicated kidney biopsy from patients with lupus: data from the Accelerating Medicines Partnership RA/SLE Network

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    Objectives In lupus nephritis the pathological diagnosis from tissue retrieved during kidney biopsy drives treatment and management. Despite recent approval of new drugs, complete remission rates remain well under aspirational levels, necessitating identification of new therapeutic targets by greater dissection of the pathways to tissue inflammation and injury. This study assessed the safety of kidney biopsies in patients with SLE enrolled in the Accelerating Medicines Partnership, a consortium formed to molecularly deconstruct nephritis.Methods 475 patients with SLE across 15 clinical sites in the USA consented to obtain tissue for research purposes during a clinically indicated kidney biopsy. Adverse events (AEs) were documented for 30 days following the procedure and were determined to be related or unrelated by all site investigators. Serious AEs were defined according to the National Institutes of Health reporting guidelines.Results 34 patients (7.2%) experienced a procedure-related AE: 30 with haematoma, 2 with jets, 1 with pain and 1 with an arteriovenous fistula. Eighteen (3.8%) experienced a serious AE requiring hospitalisation; four patients (0.8%) required a blood transfusion related to the kidney biopsy. At one site where the number of cores retrieved during the biopsy was recorded, the mean was 3.4 for those who experienced a related AE (n=9) and 3.07 for those who did not experience any AE (n=140). All related AEs resolved.Conclusions Procurement of research tissue should be considered feasible, accompanied by a complication risk likely no greater than that incurred for standard clinical purposes. In the quest for targeted treatments personalised based on molecular findings, enhanced diagnostics beyond histology will likely be required

    Erratum: “The eighth data release of the Sloan Digital Sky Survey: first data from SDSS-III” (2011, ApJS, 193, 29)

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    Section 3.5 of Aihara et al. (2011) described various sources of systematic error in the astrometry of the imaging data of the Sloan Digital Sky Survey (SDSS). In addition to these sources of error, there is an additional and more serious error, which introduces a large systematic shift in the astrometry over a large area around the north celestial pole. The region has irregular boundaries but in places extends as far south as declination δ ≈ 41◦. The sense of the shift is that the positions of all sources in the affected area are offset by roughly 250 mas in a northwest direction. We have updated the SDSS online documentation to reflect these errors, and to provide detailed quality information for each SDSS field

    The Eleventh and Twelfth Data Releases of the Sloan Digital Sky Survey: Final Data from SDSS-III

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    The third generation of the Sloan Digital Sky Survey (SDSS-III) took data from 2008 to 2014 using the original SDSS wide-field imager, the original and an upgraded multi-object fiber-fed optical spectrograph, a new near-infrared high-resolution spectrograph, and a novel optical interferometer. All of the data from SDSS-III are now made public. In particular, this paper describes Data Release 11 (DR11) including all data acquired through 2013 July, and Data Release 12 (DR12) adding data acquired through 2014 July (including all data included in previous data releases), marking the end of SDSS-III observing. Relative to our previous public release (DR10), DR12 adds one million new spectra of galaxies and quasars from the Baryon Oscillation Spectroscopic Survey (BOSS) over an additional 3000 deg2 of sky, more than triples the number of H-band spectra of stars as part of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE), and includes repeated accurate radial velocity measurements of 5500 stars from the Multi-object APO Radial Velocity Exoplanet Large-area Survey (MARVELS). The APOGEE outputs now include the measured abundances of 15 different elements for each star. In total, SDSS-III added 5200 deg2 of ugriz imaging; 155,520 spectra of 138,099 stars as part of the Sloan Exploration of Galactic Understanding and Evolution 2 (SEGUE-2) survey; 2,497,484 BOSS spectra of 1,372,737 galaxies, 294,512 quasars, and 247,216 stars over 9376 deg2; 618,080 APOGEE spectra of 156,593 stars; and 197,040 MARVELS spectra of 5513 stars. Since its first light in 1998, SDSS has imaged over 1/3 of the Celestial sphere in five bands and obtained over five million astronomical spectra. \ua9 2015. The American Astronomical Society
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