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Featured researches published by Robert D. Mayer.


The Journal of Urology | 2011

AUA Guideline for the Diagnosis and Treatment of Interstitial Cystitis/Bladder Pain Syndrome

Philip M. Hanno; David Burks; J. Quentin Clemens; Roger R. Dmochowski; Deborah R. Erickson; Mary P. FitzGerald; John B. Forrest; Barbara Gordon; Mikel Gray; Robert D. Mayer; Diane K. Newman; Leroy Nyberg; Christopher K. Payne; Ursula Wesselmann; Martha M. Faraday

PURPOSE To provide a clinical framework for the diagnosis and treatment of interstitial cystitis/bladder pain syndrome. MATERIALS AND METHODS A systematic review of the literature using the MEDLINE® database (search dates 1/1/83-7/22/09) was conducted to identify peer reviewed publications relevant to the diagnosis and treatment of interstitial cystitis/bladder pain syndrome. Insufficient evidence-based data were retrieved regarding diagnosis and, therefore, this portion of the Guideline is based on Clinical Principles and Expert Opinion statements. The review yielded an evidence base of 86 treatment articles after application of inclusion/exclusion criteria. These publications were used to create the majority of the treatment portion of the Guideline. When sufficient evidence existed, the body of evidence for a particular treatment was assigned a strength rating of A (high), B (moderate) or C (low). Additional treatment information is provided as Clinical Principles and Expert Opinion when insufficient evidence existed. See text and algorithm for definitions, and detailed diagnostic management, and treatment frameworks. RESULTS The evidence-based guideline statements are provided for diagnosis and overall management of interstitial cystitis/bladder pain syndrome as well as for various treatments. The panel identified first through sixth line treatments as well as developed guideline statements on treatments that should not be offered. CONCLUSIONS Interstitial cystitis/bladder pain syndrome is best identified and managed through use of a logical algorithm such as is presented in this Guideline. In the algorithm the panel identifies an overall management strategy for the interstitial cystitis/bladder pain syndrome patient. Diagnosis and treatment methodologies can be expected to change as the evidence base grows in the future.


The Journal of Urology | 2010

Effect of amitriptyline on symptoms in treatment naive patients with interstitial cystitis/painful bladder syndrome.

Harris E. Foster; Philip M. Hanno; J. Curtis Nickel; Christopher K. Payne; Robert D. Mayer; David Burks; Claire C. Yang; Toby C. Chai; Karl J. Kreder; Kenneth M. Peters; Emily S. Lukacz; Mary P. FitzGerald; Liyi Cen; J. Richard Landis; Kathleen J. Propert; Wei Yang; John W. Kusek; Leroy M. Nyberg

PURPOSE Amitriptyline is frequently used to treat patients with interstitial cystitis/painful bladder syndrome. The evidence to support this practice is derived mainly from a small, single site clinical trial and case reports. MATERIALS AND METHODS We conducted a multicenter, randomized, double-blind, placebo controlled clinical trial of amitriptyline in subjects with interstitial cystitis/painful bladder syndrome who were naïve to therapy. Study participants in both treatment arms received a standardized education and behavioral modification program. The drug dose was increased during a 6-week period from 10 up to 75 mg once daily. The primary outcome was a patient reported global response assessment of symptom improvement evaluated after 12 weeks of treatment. RESULTS A total of 271 subjects were randomized and 231 (85%) provided a global response assessment at 12 weeks of followup. Study participants were primarily women (83%) and white (74%), with a median age of 38 years. In an intent to treat analysis (271) the rate of response of subjects reporting moderate or marked improvement from baseline in the amitriptyline and placebo groups was 55% and 45%, respectively (p = 0.12). Of the subgroup of subjects (207) who achieved a drug dose of at least 50 mg, a significantly higher response rate was observed in the amitriptyline group (66%) compared to placebo (47%) (p = 0.01). CONCLUSIONS When all randomized subjects were considered, amitriptyline plus an education and behavioral modification program did not significantly improve symptoms in treatment naïve patients with interstitial cystitis/painful bladder syndrome. However, amitriptyline may be beneficial in persons who can achieve a daily dose of 50 mg or greater, although this subgroup comparison was not specified in advance.


Journal of the American Geriatrics Society | 2003

Use of the Agency for Health Care Policy and Research Urinary Incontinence Guideline in nursing homes

Nancy M. Watson; Carol A. Brink; James G. Zimmer; Robert D. Mayer

The objective of this study was to assess the use of the Agency for Health Care Policy and Research (now called the Agency for Healthcare Research and Quality) Urinary Incontinence (UI) Guideline (1996) in nursing homes (NHs) using retrospective chart review and nursing assistant screening interviews. The study was conducted in a nonrandom sample of 52 NHs in upstate New York. Two hundred residents developing new UI or newly admitted with UI on the dayshift and who met criteria for evaluation and treatment/management were evaluated in the 12 weeks after onset of or admission with UI. Fifteen percent of newly admitted residents needed evaluation. Of residents already in NHs, 2.3 per 100 beds developed new UI over the 12 weeks. Aspects of UI evaluation rarely done were rectal examination (15%), digital examination of prostate (15%), and pelvic examination (2%). Sixty‐eight percent had a culture/sensitivity, 56% a urinalysis, and 6% a postvoid residual. Eighty‐one percent had a reversible cause at the time of onset, but only 34% had all addressed. Few (2%) needed urologist evaluation. Treatment was rare (3%), but management using toileting and absorbent products were common. Only 6% achieved resolution of UI. These results suggest that assessment and treatment of UI is manageable (a total of 4.2 new cases per 100 beds per 12 weeks) but quality is not adequate. On average, only 20% of the standards applicable were met, due primarily to lack of awareness of new UI and lack of familiarity with the guideline. Thus, improvements are needed. Recommendations for guideline revision are made.


Cancer Chemotherapy and Pharmacology | 1987

Inhibition of cisplatin-induced nephrotoxicity in rats by buthionine sulfoximine, a glutathione synthesis inhibitor

Robert D. Mayer; Kan-ei Lee; Abraham T.K. Cockett

SummaryDL-Buthionine-(S, R)-sulfoximine (BSO), a glutathione-depleting agent, was found to diminish the nephrotoxic effect of cisplatin (cis-diamminedichloroplatinum). Pretreatment of rats with BSO (4 mmol/kg s. c.) 2 h prior to cisplatin, either as a single dose of 5 mg/kg or at a daily dose of 2.5 mg/kg for 3 consecutive days, resulted in diminished elevations of plasma BUN concentration and decreased cisplatin-induced inhibition of renal γ-glutamylcysteine synthetase and γ-glutamyl transpeptidase activity measured 6 days following treatment. Administration of BSO prior to cisplatin at 7.5 mg/kg did not significantly alter the effect of cisplatin on either BUN concentration or enzyme activity. The influence of BSO pretreatment on the antitumor activity of cisplatin was studied using implantation of a murine bladder cancer (MBT-2) in C3H mice. Pretreatment of mice with BSO (5 mmol/kg) did not influence cisplatin antitumor efficacy.


Biochemical Pharmacology | 1989

Differential effects of cyclosporin on hepatic and renal heme, cytochrome P-450 and drug metabolism: Possible role in nephrotoxicity of the drug

Robert D. Mayer; Stacey Herman; Abraham T.K. Cockett; Mahin D. Maines

Treatment of rats with 25 or 50 mg/kg cyclosporin A for 6 days elicited vastly different responses in hepatic and renal heme and drug metabolism activities. In the liver, cytochrome P-450 concentration was decreased significantly (to 70-75% of the control). This was accompanied by a marked reduction in benzo[a]pyrene hydroxylase activity (to 20-28% of the control). Aniline hydroxylation was also decreased, but to a lesser extent (to 77% of the control). In contrast, in the kidney cytochrome P-450 concentration was significantly increased to (145-170% of the control), along with a modest decrease in benzo[a]pyrene hydroxylation activity. In this organ, the concentration of porphyrins was severely decreased (to 30% of the control). Also, the activities of delta-aminolevulinate (ALA) synthetase and ALA dehydratase, as well as that of heme oxygenase, were inhibited. It is suggested that in the kidney the inhibition of degradation, rather than an enhanced rate of synthesis of the heme molecule, contributes to the observed increase in cytochrome P-450 concentration. In the liver, the decrease in the cytochrome concentration could not be explained in terms of an alteration in the rate of heme biosynthesis or degradation. Therefore, the observed decrease in cytochrome P-450 concentration could reflect the direct inactivation of the hemoprotein or regulation of apoprotein production by cyclosporin and/or its metabolite(s). The possible relevance of the observations to cyclosporin nephrotoxicity is discussed.


Urology | 1989

Effect of systemic glutathione depletion by buthionine sulfoximine on sensitivity of murine bladder cancer to cytotoxic agents.

Kan-ei Lee; Robert D. Mayer; Abraham T.K. Cockett

The effect of systemic glutathione (GSH) depletion on sensitization of bladder cancer cells to various antineoplastic agents was investigated using murine model, MBT-2. Subcutaneous injection(s) of buthionine sulfoximine (BSO) significantly depleted the GSH content in the tumor and organs. BSO pretreatment produced significant enhancement in the antitumor effect of cyclophosphamide (CY), though it failed to sensitize the tumors to doxorubicin hydrochloride (Adriamycin), cisplatin, mitomycin C, JM-8, methotrexate, vinblastine, and tumor necrosis factor. Mice tolerated cytotoxic agents alone and in combination with BSO except for cisplatin in combination with BSO. A 29 percent (4/14) mortality rate was observed in mice treated with BSO and divided schedule of cisplatin.


The Journal of Urology | 1999

THE OXIDOREDUCTASE, BILIVERDIN REDUCTASE, IS INDUCED IN HUMAN RENAL CARCINOMA - pH AND COFACTOR-SPECIFIC INCREASE IN ACTIVITY

Mahin D. Maines; Robert D. Mayer; Erdal Erturk; Tian J. Huang; Anthony Disantagnese

PURPOSE Biliverdin reductase is an oxidoreductase unique among all enzymes characterized to date in having dual pH/dual cofactor requirement - NADH and NADPH at 6.7 and 8.7, respectively. The protein shows extensive microheterogeneity that is caused by post-translational modification. The reductase converts the heme degradation product, biliverdin, to bilirubin. Bilirubin has been shown to inhibit responses of human lymphocytes, including phytohemagglutinin-induced proliferation, interleukin-2 production, and antibody dependent and independent cell mediated cytotoxicity. In addition to acting as an antioxidant, it inhibits protein phosphorylation and activity of enzymes such as protein kinase C and NADPH oxidase. This research was to evaluate whether renal cell carcinoma differs from normal tissue in regard to the expression and activity of the reductase. MATERIALS AND METHODS Kidney tissue with or without visible renal carcinoma and normal kidney tissue from a brain dead patient were frozen at -80C shortly after removal. Ten microm. tissue sections were used for immunostaining of biliverdin reductase, pooled isolated tumors and surrounding tissue that did not contain visible tumor were used for Northern blot analysis of mRNA and Western blot analysis of protein. Enzyme activity was also measured in these preparations at pH 6.7 with NADH, and at pH 8.7 with NADPH. Ten additional formalin fixed specimens of renal cell carcinoma were also used for immunostaining. RESULTS There was a striking increase in the reductase protein levels, as visualized by immunostaining in tumor tissue cells. The increase was also evident by Western blotting, and involved in increased transcription of biliverdin reductase as suggested by Northern blot analysis. The protein would also be detected in the infiltrating monocytes, macrophages, T cells and neutrophils as well as in circulating lymphocytes. The enzyme activity was nearly doubled in the tumor tissue, but selectively with NADH as the cofactor. CONCLUSION Increases in biliverdin reductase expression and activity only with NADH is found in renal cell carcinoma. The net effects of this change are uncertain at present but several pathways, which could be affected by the reductase, may alter local physiology. Biliverdin reductase as a zinc metalloprotein may directly interact with other regulatory proteins, generation of increased bilirubin may alter immune function and increased enzyme activity may deplete NADH with contrasting consequence of blocking free radical formation and depleting cellular ATP. To the benefit of the host, the latter could culminate in tumor cell death.


Urology | 2013

Polymorphism in the SCN9A Voltage-Gated Sodium Channel Gene Associated With Interstitial Cystitis/Bladder Pain Syndrome

Jay E. Reeder; Timothy Byler; David C. Foster; Steve K. Landas; Henry Okafor; Gillian Stearns; Ronald W. Wood; Yachao Zhang; Robert D. Mayer

OBJECTIVE To determine whether an association exists between interstitial cystitis/bladder pain syndrome (IC/BPS) and a nonsynonymous single nucleotide polymorphism in the SCN9A voltage-gated sodium channel gene previously associated with other chronic pain syndromes. MATERIALS AND METHODS Germline deoxyribonucleic acid was sampled from archived bladder biopsy specimens from patients with a documented diagnosis of IC/BPS. Deoxyribonucleic acid from hysterectomy specimens was obtained as a control population. The genotype of single nucleotide polymorphism rs6746030 was determined by deoxyribonucleic acid sequencing after polymerase chain reaction amplification. Contingency analysis of genotypes was performed using Pearsons chi-square test and Fishers exact test. RESULTS Polymerase chain reaction product was obtained from 26 of 31 control specimens and from 53 of 57 IC/BPS biopsy specimens. Of the 26 control subjects, 3 (11.5%) were genotype AG and 23 were GG. In contrast, AA or AG genotypes were present in 21 of 53 (39.6%) patients with IC/BPS, a statistically significant difference compared with the controls (Pearsons chi-square, P=.036). Similarly, the A allele was at a greater frequency in the IC/BPS group using Fishers exact test (P=.009). CONCLUSION These data strongly suggest that pain perception in at least a subset of patients with IC/BPS is influenced by this polymorphism in the SCN9A voltage-gated sodium channel.


The Journal of Urology | 2011

EARLY TERMINATION OF A TRIAL OF MYCOPHENOLATE MOFETIL FOR TREATMENT OF INTERSTITIAL CYSTITIS/PAINFUL BLADDER SYNDROME: LESSONS LEARNED

Claire C. Yang; David Burks; Kathleen J. Propert; Robert D. Mayer; Kenneth M. Peters; J. Curtis Nickel; Christopher K. Payne; Mary P. FitzGerald; Philip M. Hanno; Toby C. Chai; Karl J. Kreder; Emily S. Lukacz; Harris E. Foster; Liyi Cen; J. Richard Landis; John W. Kusek; Leroy M. Nyberg

PURPOSE We evaluated the efficacy and tolerability of mycophenolate mofetil in patients with treatment refractory interstitial cystitis/painful bladder syndrome. MATERIALS AND METHODS A total of 210 patients with interstitial cystitis/painful bladder syndrome were to be randomized into a multicenter, placebo controlled trial using a 2:1 randomization. Participants in whom at least 3 interstitial cystitis/painful bladder syndrome specific treatments had failed and who had at least moderately severe symptoms were enrolled in a 12-week treatment study. The primary study end point was the global response assessment. Secondary end points were general and disease specific symptom questionnaires, and voiding diaries. RESULTS Only 58 subjects were randomized before a black box warning regarding mycophenolate mofetil safety was issued by the manufacturer in October 2007. The trial was halted, and interim analysis was performed and presented to an independent data and safety monitoring board. Six of the 39 subjects (15%) randomized at study cessation were considered responders for mycophenolate mofetil compared to 3 of 19 controls (16%, p=0.67). Secondary outcome measures reflected more improvement in controls. CONCLUSIONS In a randomized, placebo controlled trial that was prematurely halted mycophenolate mofetil showed efficacy similar to that of placebo to treat symptoms of refractory interstitial cystitis/painful bladder syndrome. The results of this limited study cannot be used to confirm or refute the hypothesis that immunosuppressive therapy may be beneficial to at least a subgroup of patients with interstitial cystitis/painful bladder syndrome. Despite study termination lessons can be gleaned to inform future investigations.


Journal of Cancer Research and Clinical Oncology | 1989

Improved use of buthionine sulfoximine to prevent cisplatin nephrotoxicity in rats.

Robert D. Mayer; Kan-ei Lee; Abraham Tk Cockett

SummaryMale Sprague Dawley rats were treated with buthionine sulfoximine (BSO) and cisplatin in different doses and schedules to optimize the chemoprotective effect of BSO against cisplatin nephrotoxicity. BSO at 4 mmol/kg, administered s.c. 2 h prior to cisplatin, resulted in normal blood urea nitrogen (BUN) levels in rats treated with 3 or 4 mg/kg cisplatin, and modestly, but significantly reduced the toxicity of cisplatin at 5 mg/kg. Administration of BSO (4 mmol/kg) at intervals ranging from 0 to 16 h prior to cisplatin (5 mg/kg) resulted in a significant reduction in BUN values. A BSO dose as low as 0.04 mmol/kg was found to be as effective as 4 mmol/kg against nephrotoxicity associated with cisplatin at 4 mg/kg. Repetitive injections of BSO (1 mmol/kg every 12 h, four times, beginning 2 h prior to cisplatin) significantly inhibited elevations of BUN associated with high-dose cisplatin (6 mg/kg), whereas a single BSO injection of 4 mmol/kg was ineffective. The degree and duration of renal glutathione depletion was related to the dose of BSO. Renal glutathione content following 4 mmol/kg BSO was 38% of control at 2 h and 40% at 24 h; following 0.04 mg/kg, glutathione was 47% at 2 h and almost 100% at 24 h. Simultaneous in vitro administration of BSO did not inactivate cisplatin cytotoxicity as measured by the colony-forming ability of MBT-2 cells in soft agar. These data indicate that repeated injections of BSO, beginning prior to cisplatin administration, would improve the nephroprotective effect without compromising the chemotherapeutic efficacy of cisplatin. It is suggested that the ability of BSO to reduce cisplatin nephrotoxicity may not correlate with the degree of renal glutathione depletion and that the mechanism of action is unlikely to involve direct inactivation of cisplatin.

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Philip M. Hanno

University of Pennsylvania

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Roger R. Dmochowski

Vanderbilt University Medical Center

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John W. Kusek

National Institutes of Health

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