Caballero-Nieves, S. M., Gies, D. R., Bolton, C. T., Hadrava, P., Herrero, A., Hillwig, T. C., ...
We present an examination of high resolution, ultraviolet spectroscopy from Hubble Space Telescope of the photospheric spectrum of the O-supergiant in the massive X-ray binary HD 226868 = Cyg X-1. We...
Hoard, D. W., Wachter, S., Brinkworth, C. S., Kafka, S., Howell, S. B., Ciardi, D. R.
Cataclysmic variables have been extensively observed at optical, ultraviolet, and Xray wavelengths, where their white dwarf primary stars and bright accretion disks dominate their emitted luminosity....
Stellar wind variations during the X-ray high and low states of Cygnus X-1 (2008)
Gies, D. R., Bolton, C. T., Blake, R. M., Caballero-Nieves, S. M., Crenshaw, D. M., Hadrava, P., ...
We present results from Hubble Space Telescope ultraviolet spectroscopy of the massive X-ray and black hole binary system, HD 226868 = Cyg X-1. The spectra were obtained at both orbital conjunction...
Stellar Wind Variations During the X-ray High and Low States of Cygnus X-1 (2008)
Gies, D. R., Bolton, C. T., Blake, R. M., Caballero-Nieves, S. M., Crenshaw, D. M., Hadrava, P., ...
We present results from Hubble Space Telescope UV spectroscopy of the massive X-ray binary system, HD226868 = Cyg X-1. The spectra were obtained at both orbital conjunction phases in two separate...
Stellar wind variations during the X-ray high and low states of Cygnus X-1 (2008)
Gies, D.R., Bolton, C.T., Blake, R.M., Caballero-Nieves, S.M., Crenshaw, D.M., Hadrava, P., ...
We present results from Hubble Space Telescope ultraviolet spectroscopy of the massive X-ray and black hole binary system, HD 226868 = Cyg X-1. The spectra were obtained at both orbital conjunction...
Dhillon Littlefair Howell, V. S. Dhillon, S. P. Littlefair, S. B. Howell, D. R. Ciardi, ...
We present K-band spectra of the short-period dwarf novae YZ Cnc, LY Hya, BK Lyn, T Leo, SW UMa and WZ Sge, the novalike variables DW UMa, V1315 Aql, RW Tri, VY Scl, UU Aqr and GP Com, and a series...
Cyclotron modeling phase-resolved infrared spectroscopy of polars I: EF Eridani (2007)
Campbell, R. K., Harrison, T. E., Schwope, A. D., Howell, S. B.
We present phase-resolved low resolution infrared spectra of the polar EF Eridani obtained over a period of 2 years with SPEX on the IRTF. The spectra, covering the wavelength range 0.8 to 2.4...
Discovery of a bright eclipsing cataclysmic variable (2007)
Sing, D. K., Green, E. M., Howell, S. B., Holberg, J. B., Lopez-Morales, M., Shaw, J. S., ...
We report on the discovery of J0644+3344, a bright deeply eclipsing cataclysmic variable (CV) binary. Spectral signatures of both binary components and an accretion disk can be seen at optical...
Brinkworth, C. S., Hoard, D. W., Wachter, S., Howell, S. B., Ciardi, David R., Szkody, P., ...
We present Spitzer photometry of six short-period polars, EF Eri, V347 Pav, VV Pup, V834 Cen, GG Leo, and MR Ser. We have combined the Spitzer IRAC (3.6-8.0 μm) data with the 2MASS JHK_s photometry...
First detection of Zeeman absorption lines in the polar VV Pup (2007)
Mason, E., Wickramasinghe, D., Howell, S. B., Szkody, P.
We investigated the low state of the polar VV Pup by collecting high S/N time series spectra. We monitored VV Pup with VLT+FORS1 and analyzed the evolution of its spectroscopic features across two...
Brinkworth, C. S., Hoard, D. W., Wachter, S., Howell, S. B., Ciardi, D. R., Szkody, P., ...
We present Spitzer Space Telescope photometry of six short-period polars, EF Eri, V347 Pav, VV Pup, V834 Cen, GG Leo, and MR Ser. We have combined the Spitzer Infrared Array Camera (3.6 -8.0 microns)...
A Photometric and Spectroscopic Study of the Cataclysmic Variable ST LMi during 2005-2006 (2006)
Kafka, S., Howell, S. B., Honeycutt, R. K., Robertson, J. W.
We present orbit-resolved spectroscopic and photometric observations of the polar ST LMi during its recent low and high states. In the low state spectra, we report the presence of blue and red...
Color and Variability Characteristics of Point Sources in the Faint Sky Variability Survey (2006)
Huber, M. E., Everett, M. E., Howell, S. B.
We present an analysis of the color and variability characteristics for point sources in the Faint Sky Variability Survey (FSVS). The FSVS cataloged ~23 square degrees in BVI filters from ~16--24 mag...
The First Direct Spectroscopic Detection of a White Dwarf Primary in an AM CVn System (2006)
Sion, E. M., Solheim, J. E., Szkody, P., Gaensicke, B. T., Howell, S. B.
We report the results of a synthetic spectral analysis of Hubble STIS spectra of the AM CVn-type cataclysmic variable CP Eri obtained when the system was in quiescence. The FUV spectrum is best...
On the new short orbital period cataclysmic variable Halpha0242-2802 (2005)
We present results from our phase-resolved spectroscopy of the newly identified cataclysmic variable Halpha0242-2802. Halpha0242-2802 was identified from a deep UK Schmidt Halpha-R band survey as a...
The accreting white dwarfs in BW Scl, BC UMa and SW UMa (2005)
Gaensicke, B. T., Szkody, P., Howell, S. B., Sion, E. M.
We have observed the short-period dwarf novae BW Scl, BC UMa and SW UMa using the Hubble Space Telescope/Space Telescope Imaging Spectrograph. In all three systems, the white dwarf is the dominant...
Simultaneous X-ray and Optical Observations of EX Hydrae (2005)
Belle, K. E., Howell, S. B., Mukai, K., Szkody, P., Nishikida, K., Ciardi, D. R., ...
The intermediate polar, EX Hydrae, was the object of a large simultaneous multiwavelength observational campaign during 2000 May - June. Here we present the Rossi X-ray Timing Explorer photometry and...
Dobbie, P.D., Burleigh, Matthew R., Levan, Andrew J., Barstow, Martin A., Napiwotzki, R., Holberg, J.B., ...
A near-IR spectroscopic search for very-low-mass cool companions to notable DA white dwarfs (2004)
Dobbie, P. D., Burleigh, M. R., Levan, A. J., Barstow, M. A., Napiwotzki, R., Holberg, J. B., ...
We have undertaken a detailed near-IR spectroscopic analysis of eight notable white dwarfs, predominantly of southern declination. In each case the spectrum failed to reveal compelling evidence for...
A Preliminary Observational Search for Circumbinary Disks Around Cataclysmic Variables (2004)
Belle, K. E., Sanghi, N., Howell, S. B., Holberg, J. B., Williams, P. T.
Circumbinary (CB) disks have been proposed as a mechanism to extract orbital angular momentum from cataclysmic variables (CVs) during their evolution. As proposed by Taam & Spruit, these disks extend...
Spectroscopic Observations of Twenty-one Faint Cataclysmic Variables Candidates (2003)
We provide the first minimum light spectroscopic observations for 21 previously known or suspected faint cataclysmic variable candidates. The sources were selected from the Downes et al. (2001)...
The surprising Far-UV spectrum of the polar BY Camelopardalis (2003)
Mouchet, M., Bonnet-Bidaud, J. M., Roueff, E., Beuermann, K., De Martino, D., Desert, J. M., ...
We report on the first far-UV observations of the asynchronous polar BY Cam made by the Far-Ultraviolet Spectroscopic Explorer (FUSE). The source is known to exhibit the most extreme NV/CIV emission...
HST/STIS Spectroscopy of the Intermediate Polar EX Hydrae (2003)
Belle, K. E., Howell, S. B., Sion, E. M., Long, K. S., Szkody, P.
We present the results of our analysis of six orbits of HST/STIS time-tagged spectroscopy of the intermediate polar, EX Hydrae. The high time and wavelength resolution of the HST/STIS spectra...
The Faint Sky Variability Survey - I. Goals and data reduction process (2003)
Groot, P.J., Vreeswijk, P.M., Huber, M.E., Everett, M., Howell, S.B., Nelemans, G.A., ...
The surprising Far-UV spectrum of the polar BY Camelopardalis (2003)
Mouchet, M., Roueff, E., Beuermann, K., De Martino, D., Desert, J. M., ...
Loss of atm sensitises p53-deficient cells to topoisomerase poisons and antimetabolites (2003)
Fedier, A., Schlamminger, M., Schwarz, V. A., Haller, U., Howell, S. B., Fink, D.
Background: Ataxia-telangiectasia is a pleiotropic autosomal recessive disorder caused by mutations in the ATM gene. In addition to a profound cancer predisposition, another hallmark of...
Discovery of Two New Faint Cataclysmic Variables (2002)
Howell, S. B., Mason, E., Huber, M., Clowes, R.
We report on the discovery of two new faint cataclysmic variables. The objects were selected as candidates from two different imaging surveys aimed at the discovery of such faint systems. One survey...
Mason, E., Howell, S. B., Szkody, P., Harrison, T. E., Holtzman, J. A., Hoard, D. W.
We present multi-color photometry and time resolved spectroscopy of OU Vir. The analysis of the quiescent light curve shows that OU Vir is characterized by i) strong cycle-to-cycle brightness...
HST Spectra of GW Librae: A Hot Pulsating White Dwarf in a Cataclysmic Variable (2002)
Szkody, P., Gansicke, B., Howell, S. B., Sion, E.
We have obtained Hubble Space Telescope UV spectra of the white dwarf in GW Lib, the only known non-radially pulsating white dwarf in a cataclysmic variable, and the first known DAZQ variable. The UV...
Howell, S. B., Fried, R., Szkody, P., Sirk, M., Schmidt, G.
We obtained EUV photometry, optical spectroscopy, and multi-color optical photometry for WX Cet during its 1998 November superoutburst. WX Cet is only the second short-period, low mass transfer CV...
High spectral resolution time-resolved optical spectroscopy of V893 Sco (2001)
Mason, E., Skidmore, W., Howell, S. B., Mennickent, R. E.
We present high resolution time-resolved optical spectra of the high inclination short orbital period dwarf nova V893 Sco. We performed spectral analysis through radial velocity measurements, Doppler...
On the Masses of the Secondary Stars in CVs (2001)
Recent theoretical efforts have made predictions for the masses of the secondary stars in cataclysmic variables. Accurate observational determinations for M$_2$ are sparse and typically have...
Simultaneous EUV and IR Observations of the Eclipsing Polar HU Aqr (2001)
Howell, S. B., Ciardi, D. R., Sirk, M. M., Schwope, A. D.
We present simultaneous EUV and infrared (J,K) observations of the polar HU Aqr obtained during August 1998 when the star was in a high mass accretion state. EUV and IR light curves and EUV spectra...
Bonetti, A., Zaninelli, M., Leone, R., Franceschi, T., Fraccon, A. P., Pasini, F., ...
Background: It has been proposed that the activity of a second-line treatment regimen can be documented by showing that the time to progression (TTP) following second-line therapy is longer than the...
The Faint Sky Variability Survey I: An Overview (2000)
Groot, P. J., Vreeswijk, P. M., Everett, M. E., Howell, S. B.
The Faint Sky Variability Survey is aimed at finding variable objects in the brightness range between 17th and 25th magnitude on timescales between tens of minutes and years with photometric...
The Faint Sky Variability Survey II: Initial Results (2000)
Everett, M. E., Huber, M. E., Howell, S. B.
We discuss the first results from the Faint Sky Variability Survey (Groot et al. 2000). The data consist of V-band light curves, BVI colours, astrometry, and morphology information on several hundred...
Mason, E., Skidmore, W., Howell, S. B., Ciardi, D. R., Littlefair, S., Dhillon, V. S.
We present our second paper describing multi-wave-band, time-resolved spectroscopy of WZ Sge. We analyze the evolution of both optical and IR emission lines throughout the orbital period and find...
Dhillon, V. S., Littlefair, S. P., Howell, S. B., Ciardi, D. R., Harrop-Allin, M. K., Marsh, T. R.
We present K-band spectra of the short-period dwarf novae YZ Cnc, LY Hya, BK Lyn, T Leo, SW UMa and WZ Sge, the novalike variables DW UMa, V1315 Aql, RW Tri, VY Scl, UU Aqr and GP Com, and a series...
J-band spectroscopy of cataclysmic variables (1999)
Littlefair, S. P., Dhillon, V. S., Howell, S. B., Ciardi, D. R.
We present time resolved J-band (1.025 - 1.340 micron) infrared spectra of the short-period dwarf novae (DNe) WZ Sge, VY Aqr and single spectra of the short-period DN EF Peg and the novalike variable...
Going faint and variable: the faint sky variability survey (1999)
Groot, P.J., Everett, M., Howell, S.B., Vreeswijk, P.M., Huber, M., Paradijs, J.A. Van
Multiwavelength superoutburst observations of T Leonis (1999)
Howell, S.B., Ciardi, D.R., Szkody, P., Paradijs, J.A. Van, Kuulkers, E., Cash, J., ...
Phase-resolved Hubble Space Telescope ultraviolet spectroscopy of V795 Her. (1998)
Rosen, S.R., Prinja, R.K., Drew, J.E., Mason, K.O., Howell, S.B.
‘The definitive version is available at www.blackwell-synergy.com.’ Copyright Blackwell Publishing. DOI: 10.1046/j.1365-8711.1998.01844.x [Full text of this article is not available in the UHRA]
Infrared and Optical Spectroscopy of Type Ia Supernovae in the Nebular Phase (1997)
Bowers, E. J. C., Meikle, W. P. S., Geballe, T. R., Walton, N. A., Pinto, P. A., Dhillon, V. S., ...
We present near-infrared (NIR) spectra for Type Ia supernovae at epochs of 13 to 338 days after maximum blue light. Some contemporary optical spectra are also shown. All the NIR spectra exhibit...
Dose intensification of cisplatin chemotherapy through biweekly administration (1993)
Kim, S., Howell, S. B., McClay, E., Kirmani, S., Goel, R., Plaxe, S., ...
Purpose Dose intensity (DI, expressed in mg/m2wk) may be an important factor in the clinical use of cisplatin (DDP). We have explored the shortening of the cycle interval as a way to increase the...
Christen, R D, Jekunen, A P, Jones, J A, Thiebaut, F, Shalinsky, D R, Howell, S B
We have previously shown that forskolin and 3-isobutyl-1-methylxanthine (IBMX) increased accumulation of cisplatin (DDP) in DDP-sensitive 2008 human ovarian carcinoma cells in proportion to their...
Christen, R D, Hom, D K, Porter, D C, Andrews, P A, MacLeod, C L, Hafstrom, L, ...
Cisplatin (DDP) is the most effective drug for the treatment of human ovarian cancer, but the mechanisms that determine sensitivity to the cytotoxic action of DDP are not well understood. Treatment...
Isobologram analysis was used to examine the interaction between 1-beta-D-arabinofuranosylcytosine (Ara-C), thymidine (dThd), and hydroxyurea. All three pairs of drugs, as well as the triple...
Zhen, W, Link, C J, O'Connor, P M, Reed, E, Parker, R, Howell, S B, ...
We have studied several aspects of DNA damage formation and repair in human ovarian cancer cell lines which have become resistant to cisplatin through continued exposure to the anticancer drug. The...
Howell, S B, Chu, B B, Wung, W E, Metha, B M, Mendelsohn, J
18 patients with malignant effusions were treated with continuous intraperitoneal, intrapleural, or intrapericardial infusion of methotrexate (MTX) 30 mg/m2 per d combined with simultaneous...
Cross-resistance between cisplatin, antimony potassium tartrate, and arsenite in human tumor cells.
Naredi, P, Heath, D D, Enns, R E, Howell, S B
Cross-resistance between cisplatin (DDP) and metalloid salts in human cells was sought on the basis that mechanisms that mediate metalloid salt cross-resistance in prokaryotes are evolutionarily...
Isonishi, S, Jekunen, A P, Hom, D K, Eastman, A, Edelstein, P S, Thiebaut, F B, ...
A twofold change in the cisplatin (DDP) sensitivity of 2008 human ovarian carcinoma cells is sufficient to reduce tumor response in vivo. The DDP sensitivity of these cells can be enhanced by...
Regulation of de novo purine synthesis in human bone marrow mononuclear cells by hypoxanthine.
King, M E, Honeysett, J M, Howell, S B
In previous studies from this laboratory, human bone marrow hypoxanthine concentrations were found to average 7.1 microM, three times higher than plasma hypoxanthine concentrations measured...
Christen, R D, Jekunen, A P, Jones, J A, Thiebaut, F, Shalinsky, D R, Howell, S B
We have previously shown that forskolin and 3-isobutyl-1-methylxanthine (IBMX) increased accumulation of cisplatin (DDP) in DDP-sensitive 2008 human ovarian carcinoma cells in proportion to their...
Christen, R D, Hom, D K, Porter, D C, Andrews, P A, MacLeod, C L, Hafstrom, L, ...
Cisplatin (DDP) is the most effective drug for the treatment of human ovarian cancer, but the mechanisms that determine sensitivity to the cytotoxic action of DDP are not well understood. Treatment...
Isobologram analysis was used to examine the interaction between 1-beta-D-arabinofuranosylcytosine (Ara-C), thymidine (dThd), and hydroxyurea. All three pairs of drugs, as well as the triple...
Zhen, W, Link, C J, O'Connor, P M, Reed, E, Parker, R, Howell, S B, ...
We have studied several aspects of DNA damage formation and repair in human ovarian cancer cell lines which have become resistant to cisplatin through continued exposure to the anticancer drug. The...
Howell, S B, Chu, B B, Wung, W E, Metha, B M, Mendelsohn, J
18 patients with malignant effusions were treated with continuous intraperitoneal, intrapleural, or intrapericardial infusion of methotrexate (MTX) 30 mg/m2 per d combined with simultaneous...
Cross-resistance between cisplatin, antimony potassium tartrate, and arsenite in human tumor cells.
Naredi, P, Heath, D D, Enns, R E, Howell, S B
Cross-resistance between cisplatin (DDP) and metalloid salts in human cells was sought on the basis that mechanisms that mediate metalloid salt cross-resistance in prokaryotes are evolutionarily...
Isonishi, S, Jekunen, A P, Hom, D K, Eastman, A, Edelstein, P S, Thiebaut, F B, ...
A twofold change in the cisplatin (DDP) sensitivity of 2008 human ovarian carcinoma cells is sufficient to reduce tumor response in vivo. The DDP sensitivity of these cells can be enhanced by...
Regulation of de novo purine synthesis in human bone marrow mononuclear cells by hypoxanthine.
King, M E, Honeysett, J M, Howell, S B
In previous studies from this laboratory, human bone marrow hypoxanthine concentrations were found to average 7.1 microM, three times higher than plasma hypoxanthine concentrations measured...
Regulation of initial vinblastine influx by P-glycoprotein.
Shalinsky, D. R., Jekunen, A. P., Alcaraz, J. E., Christen, R. D., Kim, S., Khatibi, S., ...
P-glycoprotein (PGP) is an energy-dependent efflux pump that serves to protect cells against the cytotoxicity of many natural product drugs including vinblastine (VBL). In this study we investigated...
Shalinsky, D. R., Heath, D. D., Jekunen, A. P., Alcaraz, J. E., Howell, S. B.
The ability of 1,9-dideoxyforskolin (DDF), 1-deoxyforskolin (DF) and forskolin to modulate cellular sensitivity to vinblastine (VBL) was examined in drug-sensitive parental KB-3-1 cells and a...
Cellular accumulation of the anticancer agent cisplatin: a review.
Acquired resistance to cisplatin (DDP) is a major clinical problem in the treatment of ovarian, testicular, and head and neck carcinomas; decreased accumulation of DDP is the most consistently...
Synergistic interaction between cisplatin and taxol in human ovarian carcinoma cells in vitro.
Jekunen, A. P., Christen, R. D., Shalinsky, D. R., Howell, S. B.
Taxol, a unique tubulin active agent, was found to demonstrate a marked schedule-dependent synergistic interaction with cisplatin (DDP) in the killing of human ovarian carcinoma 2008 cells in vitro...
Isonishi, S., Hom, D. K., Eastman, A., Howell, S. B.
Sensitivity to platinum-containing drugs is believed to be a function of how much drug enters the cell, the extent of DNA adduct formation and the rate at which DNA is repaired. Activation of protein...
Shalinsky, D. R., Slovak, M. L., Howell, S. B.
We examined the ability of dipyridamole (DPM) to act synergistically with vinblastine (VBL) in HT1080 fibrosarcoma cells and a drug-resistant variant, HT1080/DR4, which lacks mdr1 expression, in...
McClay, E. F., Albright, K. D., Jones, J. A., Christen, R. D., Howell, S. B.
The development of resistance to cisplatin (DDP) occurs rapidly both in vitro and in vivo, and constitutes a major obstacle to effective therapy. We have previously demonstrated that there is a...
Gately, D. P., Jones, J. A., Christen, R., Barton, R. M., Los, G., Howell, S. B.
The inability to assess the extent of tumour damage immediately following treatment is a major clinical obstacle to improving the management of cancer patients. Normally, the effectiveness of...
Enhancement of drug sensitivity of human malignancies by epidermal growth factor.
Kröning, R., Jones, J. A., Hom, D. K., Chuang, C. C., Sanga, R., Los, G., ...
We have previously shown that epidermal growth factor (EGF) enhances the in vitro and in vivo sensitivity of human ovarian carcinoma 2008 cells to cisplatin. EGF was found to enhance selectively the...
Gately, D. P., Sharma, A., Christen, R. D., Howell, S. B.
Signal transduction pathways activated by injury play a central role in coordinating the cellular responses that determine whether a cell survives or dies. GADD153 expression increases markedly in...
Fink, D., Nebel, S., Norris, P. S., Aebi, S., Kim, H. K., Haas, M., ...
Loss of DNA mismatch repair is a common finding in hereditary non-polyposis colon cancer as well as in many types of sporadic human tumours. We compared the effect of loss of DNA mismatch repair on...
Expression of the DNA mismatch repair proteins hMLH1 and hPMS2 in normal human tissues.
Fink, D., Nebel, S., Aebi, S., Zheng, H., Kim, H. K., Christen, R. D., ...
hMLH1 and hPMS2 are part of the DNA mismatch repair complex. Mutations in these genes have been linked to hereditary non-polyposis colon cancer; they also occur in a variety of sporadic cancers....
Nehmé, A, Baskaran, R, Nebel, S, Fink, D, Howell, S B, Wang, J Y J, ...
Loss of DNA mismatch repair has been observed in a variety of human cancers. Recent studies have shown that loss of DNA mismatch repair results in resistance to cisplatin but not oxaliplatin,...
Loss of DNA mismatch repair facilitates reactivation of a reporter plasmid damaged by cisplatin
Cenni, B, Kim, H-K, Bubley, G J, Aebi, S, Fink, D, Teicher, B A, ...
Isonishi, S, Ohkawa, K, Tanaka, T, Howell, S B
Down-regulation of protein kinase C (PKC) by 12- O -tetradecanoylphorbol-13-acetate (TPA) enhances the sensitivity of human ovarian carcinoma 2008 cells to various types of platinum compounds such as...
Identification of genes differentially expressed in association with acquired cisplatin resistance
Johnsson, A, Zeelenberg, I, Min, Y, Hilinski, J, Berry, C, Howell, S B, ...
The goal of this study was to identify genes whose mRNA levels are differentially expressed in human cells with acquired cisplatin (cDDP) resistance. Using the parental UMSCC10b head and neck...
Jaeckle, K A, Phuphanich, S, Aiken, R, Batchelor, T, Campbell, T, ...
DepoCyte is a slow-release formulation of cytarabine designed for intrathecal administration. The goal of this multi-centre cohort study was to determine the safety and efficacy of DepoCyte for the...