Louise Ryan

Dr. Louise Ryan

School of Mathematical and Physical Sciences, University of Technology Sydney, NSW 2007, Australia
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Research Focus & Metrics

Academic Career Length

42Years (1985-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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12 April 2001 in New England Journal of Medicine
Verified
Journal Article
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LHLewis B. Holmes
Lewis B. Holmes
EHElizabeth A. Harvey
Elizabeth A. Harvey
BCBrent A. Coull
Brent A. Coull
KHKelly B. Huntington
Kelly B. Huntington
SKShahram Khoshbin
Shahram Khoshbin
Louise RyanLouise Ryan
Louise Ryan
The frequency of major malformations, growth retardation, and hypoplasia of the midface and fingers, known as anticonvulsant embryopathy, is increased in infants exposed to anticonvulsant drugs in utero. However, whether the abnormalities are caused by the maternal epilepsy itself or by exposure to anticonvulsant drugs is not known.

8 September 1988 in New England Journal of Medicine
Verified
Journal Article
Closed access
KAKaren S. Antman
Karen S. Antman
JGJames D. Griffin
James D. Griffin
AEAnthony Elias
Anthony Elias
MSMark A. Socinski
Mark A. Socinski
Louise RyanLouise Ryan
Louise Ryan
LSLowell E. Schnipper
Lowell E. Schnipper
An increase in the dose of chemotherapy enhances the response of many experimental and clinical cancers, but the extent of dose escalation is often limited by myelosuppression. In preliminary trials, recombinant human granulocytemacrophage colony-stimulating factor (rhGM-CSF) has augmented leukocyte numbers and function, but the optimal dose is not established.

1 July 1993 in Journal of Clinical Oncology
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Journal Article
Closed access
JEJ H Edmonson
J H Edmonson
Louise RyanLouise Ryan
Louise Ryan
RBR H Blum
R H Blum
JBJ S Brooks
J S Brooks
MSM Shiraki
M Shiraki
DPD R Parkinson
D R Parkinson
PURPOSE: This three-armed phase III study in adults with advanced soft tissue sarcomas was planned as a comparison of objective regression rates, toxicity, and survival of patients receiving doxorubicin alone, ifosfamide plus doxorubicin, and mitomycin plus doxorubicin plus cisplatin. PATIENTS AND METHODS: Between December 1987 and July 1990, 279 patients with histologically confirmed sarcomas were enrolled to receive treatment A (doxorubicin 80 mg/m2), treatment B (ifosfamide 7.5 g/m2 plus doxorubicin 60 mg/m2), or treatment C (mitomycin 8 mg/m2 plus doxorubicin 40 mg/m2 plus cisplatin 60 mg/m2). RESULTS: Of 262 assessable patients, 74 (29%) achieved objective tumor regression. Objective regression occurred in 20% of the 90 patients who received doxorubicin alone (complete remission [CR] rate, 2%), in 34% of the 88 who received ifosfamide plus doxorubicin (CR rate, 3%), and in 32% of the 84 who received mitomycin plus doxorubicin plus cisplatin (CR rate, 7%). With grade 3 or greater myelosuppression in 53% of group A, 80% of group B, and 55% of group C, regimen B was significantly more myelosuppressive than either regimen A or C (P = .01) with two, three, and one treatment-related deaths, respectively. Synovial sarcomas were responsive to ifosfamide plus doxorubicin, especially among patients younger than 40 years of age. CONCLUSION: Ifosfamide plus doxorubicin produced a significantly higher regression rate (P = .03) than did doxorubicin alone; however, this was achieved at a level of myelosuppression significantly more intense than that produced by the single agent or by the three-drug combination. Mitomycin, doxorubicin, and cisplatin also appeared to be more active than the single agent; however, at a myelosuppression level similar to that of doxorubicin alone, this trend (P = .07) did not attain the usual level for significance. No significant survival differences were observed.

7 November 2006 in Human Reproduction
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Journal Article
Open access
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RHR. Hauser
R. Hauser
JMJohn Meeker
John Meeker
NSN.P. Singh
N.P. Singh
MSM.J. Silva
M.J. Silva
Louise RyanLouise Ryan
Louise Ryan
ACA.M. Calafat
A.M. Calafat
BACKGROUND: The ubiquitous use of phthalate esters in plastics, personal care products and food packaging materials results in widespread general population exposure. In this report, we extend our preliminary study on the relationship between urinary concentrations of phthalate metabolites and sperm DNA damage among a larger sample of men and include measurements of mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) and mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP), two oxidative metabolites of di-(2-ethylhexyl) phthalate (DEHP). METHODS: Among 379 men from an infertility clinic, urinary concentrations of phthalate metabolites were measured using isotope-dilution high-performance liquid chromatography–tandem mass spectrometry. Sperm DNA damage measurements, assessed with the neutral comet assay, included comet extent (CE), percentage of DNA in tail (Tail%) and tail distributed moment (TDM). RESULTS: Monoethyl phthalate (MEP), a metabolite of diethyl phthalate, was associated with increased DNA damage, confirming our previous findings. Mono-(2-ethylhexyl) phthalate (MEHP), a metabolite of DEHP, was associated with DNA damage after adjustment for the oxidative DEHP metabolites. After adjustment for MEHHP, for an interquartile range increase in urinary MEHP, CE increased 17.3% [95% confidence interval (CI) = 8.7–25.7%], TDM increased 14.3% (95% CI = 6.8–21.7%) and Tail% increased 17.5% (95% CI = 3.5–31.5%). CONCLUSIONS: Sperm DNA damage was associated with MEP and with MEHP after adjusting for DEHP oxidative metabolites, which may serve as phenotypic markers of DEHP metabolism to ‘less toxic’ metabolites. The urinary levels of phthalate metabolites among these men were similar to those reported for the US general population, suggesting that exposure to some phthalates may affect the population distribution of sperm DNA damage.

1 May 2003 in Epidemiology
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Journal Article
Closed access
SDSusan M. Duty
Susan M. Duty
MSManori J. Silva
Manori J. Silva
DBDana B. Barr
Dana B. Barr
JBJohn W. Brock
John W. Brock
Louise RyanLouise Ryan
Louise Ryan
RHRuss Hauser
Russ Hauser
There is scientific and public concern about commonly used chemicals, including phthalates, that are associated with reproductive toxicity in laboratory animals and are hormonally active. People are exposed to phthalates through diet, consumer products and medical devices. The present study explored whether environmental levels of phthalates are associated with altered semen quality in humans. We recruited 168 men who were part of subfertile couples and who presented to the Massachusetts General Hospital andrology laboratory for semen analysis between January 2000 and April 2001. Semen parameters were dichotomized based on 1999 World Health Organization reference values for sperm concentration (<20 million/ml) and motility (<50% motile), as well as Tygerberg Strict criteria for morphology (<4% normal). The comparison group was men for whom these semen parameters were all above the reference values. In urine, eight phthalate metabolites were measured with high-performance liquid chromatography and tandem mass spectrometry. Specific gravity-adjusted phthalate metabolite levels were categorized into tertiles. There was a dose-response relation between tertiles of mono-butyl phthalate and sperm motility (odds ratio per tertile = 1.0, 1.8, 3.0;P-value for trend = 0.02) and sperm concentration (1.0, 1.4, 3.3;P-value for trend = 0.07). In addition, there was a dose-response relation between tertiles of monobenzyl phthalate and sperm concentration (1.0, 1.4, 5.5;P-value for trend = 0.02). There were dose-response relations for mono-butyl phthalate and monobenzyl phthalate with one or more semen parameters, and suggestive evidence for monomethyl phthalate with sperm morphology. The lack of a relation for other phthalates may indicate a difference in spermatotoxicity among phthalates.

30 January 1998 in Statistics in Medicine
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Journal Article
Closed access
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JLJane C. Lindsey
Jane C. Lindsey
Louise RyanLouise Ryan
Louise Ryan