Mark R. Conaway

Bio: Mark R. Conaway is an academic researcher from University of Virginia. The author has contributed to research in topics: Cancer & Population. The author has an hindex of 65, co-authored 282 publications receiving 14047 citations. Previous affiliations of Mark R. Conaway include University of Virginia Health System & Duke University.

Hydrocortisone With or Without Mitoxantrone in Men With Hormone-Refractory Prostate Cancer: Results of the Cancer and Leukemia Group B 9182 Study

Abstract: PURPOSE: Approximately 40,000 men die each year of hormone-refractory prostate cancer (HRPC). The results of treatment with chemotherapy have been disappointing to date, with no trials demonstrating a benefit with respect to survival duration. Corticosteroids and mitoxantrone each have been shown to be active agents in this disease. The purpose of this study was to demonstrate an advantage of mitoxantrone and hydrocortisone (M+H) over hydrocortisone alone with respect to survival duration. PATIENTS AND METHODS: Two hundred forty-two patients with HRPC were randomized to receive either M+H or hydrocortisone alone. Patients were monitored for survival, time to disease progression, time to treatment failure, response, and quality-of-life (QOL) parameters. RESULTS: Treatment in both arms was well tolerated. Although there was a delay in time to treatment failure and disease progression in favor of M+H over hydrocortisone alone, there was no difference in overall survival (12.3 months for M+H v 12.6 months for...

Discovery and validation of new protein biomarkers for urothelial cancer: a prospective analysis

Abstract: Summary Background Non-invasive methods for diagnosis of urothelial carcinoma have reduced specificity in patients with non-malignant genitourinary disease or other disorders. We aimed to use mass spectrometry and bioinformatics to define and validate a cancer-specific proteomic pattern. Methods We used capillary-electrophoresis-coupled mass spectrometry to obtain polypeptide patterns from urine samples of 46 patients with urothelial carcinoma and 33 healthy volunteers. From signatures of polypeptide mass, we established a model for predicting the presence of cancer. The model was refined further by use of 366 urine samples obtained from other healthy volunteers and patients with malignant and non-malignant genitourinary disease. We estimated the proportion of correct classifications from the refined model by applying it to a masked group containing 31 patients with urothelial carcinoma, 11 healthy individuals, and 138 patients with non-malignant genitourinary disease. We also sequenced several diagnostic polypeptides for urothelial carcinoma. Findings We identified a diagnostic urothelial-carcinoma pattern of 22 polypeptide masses. On masked assessment, prediction models based on these polypeptides correctly classified all samples of urothelial carcinoma (sensitivity 100% [95% CI 87–100) and all healthy samples (specificity 100% [84–100]). Correct identification of patients with urothelial carcinoma from those with other malignant and non-malignant genitourinary disease ranged from 86% to 100%. A prominent polypeptide from the diagnostic pattern for urothelial carcinoma was identified as fibrinopeptide A—a known biomarker of ovarian cancer and gastric cancer. Interpretation Validation of a highly specific biomarker pattern for urothelial carcinoma in a large group of patients with various urological disorders could be used in the diagnosis of other diseases that are identified in urine samples or in other body fluids.

Effect of exogenous surfactant (calfactant) in pediatric acute lung injury : a randomized controlled trial

Abstract: ContextDespite evidence that patients with acute lung injury (ALI) have pulmonary surfactant dysfunction, trials of several surfactant preparations to treat adults with ALI have not been successful. Preliminary studies in children with ALI have shown that instillation of a natural lung surfactant (calfactant) containing high levels of surfactant-specific protein B may be beneficial.ObjectiveTo determine if endotracheal instillation of calfactant in infants, children, and adolescents with ALI would shorten the course of respiratory failure.Design, Setting, and PatientsA multicenter, randomized, blinded trial of calfactant compared with placebo in 153 infants, children, and adolescents with respiratory failure from ALI conducted from July 2000 to July 2003. Twenty-one tertiary care pediatric intensive care units participated. Entry criteria included age 1 week to 21 years, enrollment within 48 hours of endotracheal intubation, radiological evidence of bilateral lung disease, and an oxygenation index higher than 7. Premature infants and children with preexisting lung, cardiac, or central nervous system disease were excluded.InterventionTreatment with intratracheal instillation of 2 doses of 80 mL/m2 calfactant or an equal volume of air placebo administered 12 hours apart.Main Outcome MeasuresVentilator-free days and mortality; secondary outcome measures were hospital course, adverse events, and failure of conventional mechanical ventilation.ResultsThe calfactant group experienced an acute mean (SD) decrease in oxygenation index from 20 (12.9) to 13.9 (9.6) after 12 hours compared with the placebo group’s decrease from 20.5 (14.7) to 15.1 (9.0) (P = .01). Mortality was significantly greater in the placebo group compared with the calfactant group (27/75 vs 15/77; odds ratio, 2.32; 95% confidence interval, 1.15-4.85), although ventilator-free days were not different. More patients in the placebo group did not respond to conventional mechanical ventilation. There were no differences in long-term complications.ConclusionsCalfactant acutely improved oxygenation and significantly decreased mortality in infants, children, and adolescents with ALI although no significant decrease in the course of respiratory failure measured by duration of ventilator therapy, intensive care unit, or hospital stay was observed.

Bone Density and Metabolism in Children and Adolescents With Moderate to Severe Cerebral Palsy

Abstract: Objectives. Diminished bone density and a propensity to fracture with minimal trauma are common in children and adolescents with moderate to severe cerebral palsy (CP). The purpose of this study was to provide a detailed evaluation of bone mineral density (BMD) and metabolism in this population and to assess the relationship of these measures to multiple other clin- ical, growth, and nutrition variables. Methods. The study group consisted of 117 subjects ages 2 to 19 years (mean: 9.7 years) with moderate to severe CP as defined by the Gross Motor Functional Classification scale. Population-based sampling was used to recruit 62 of the participants, which allows for estimations of prevalence. The remaining 55 subjects were a convenience sampling from both hospital- and school-based sources. The evaluation included measures of BMD, a detailed anthropometric assessment of growth and nutritional status, medical and surgical history, the Child Health Status Questionnaire, and multiple serum analyses. BMD was measured in the distal femur, a site specifically developed for use in this contracted popula- tion, and the lumbar spine. BMD measures were con- verted to age and gender normalized z scores based on our own previously published control series (n > 250). Results. Osteopenia (BMD z score <2.0) was found in the femur of 77% of the population-based cohort and in 97% of all study participants who were unable to stand and were older than 9 years. BMD was not as low in the lumbar spine (population-based cohort mean standard error z score: 1.8 0.1) as in the distal femur (mean z score: 3.1 0.2). Fractures had occurred in 26% of the children who were older than 10 years. Multiple clinical and nutritional variables correlated with BMD z scores, but interpretation of these findings is complicated by covariance among variables. In stepwise regression anal- yses, it was found that severity of neurologic impairment as graded by Gross Motor Functional Classification level, increasing difficulty feeding the child, use of anticonvul- sants, and lower triceps skinfold z scores (in decreasing order of importance) all independently contribute to lower BMD z scores in the femur. Conclusions. Low BMD is prevalent in children with moderate to severe CP and is associated with significant fracture risk. The underlying pathophysiology is com- plex, with multiple factors contributing to the problem and significant variation between different regions of the skeleton. Pediatrics 2002;110(1). URL: http://www. pediatrics.org/cgi/content/full/110/1/e5; cerebral palsy, bone mineral density, osteoporosis, pediatrics, bone me- tabolism, growth, nutrition, osteopenia.

Feeding Dysfunction is Associated with Poor Growth and Health Status in Children with Cerebral Palsy

Abstract: Objective To describe parent-reported feeding dysfunction and its association with health and nutritional status in children with cerebral palsy. Design Anthropometry was measured and z scores calculated. The Child Health Questionnaire was used to assess health status, and a categorical scale (none to severe) was used to classify subjects according to severity of feeding dysfunction. Subjects 230 children (9.7±4.6 years; 59% boys) with moderate to severe cerebral palsy were recruited from 6 centers in the United States and Canada. Statistical analyses Descriptive statistics, the Kruskal-Wallis and Pearson χ 2 tests. Results Severity of feeding dysfunction was strongly associated with indicators of poor health and nutritional status. The mean weight z scores were −1.7, −2.5, −3.3, and −1.8 among children with none, mild, moderate, or severe (largely tube-fed) feeding dysfunction, respectively ( P =.003). Similar results were observed for height z score ( P =.008), triceps z score ( P =.03), and poor Global Health score (part of the Child Health Questionnaire) ( P P =.014) and had greater body fat stores (triceps z score, P =.001) than orally fed subjects with similar motor impairment. For subjects exclusively fed by mouth, a dose-response relationship was observed between feeding dysfunction severity and poor nutritional status. Subjects with only mild feeding dysfunction had reduced triceps z score (−.9) compared with those with no feeding problems (−0.3). Conclusion For children with moderate to severe cerebral palsy, feeding dysfunction is a common problem associated with poor health and nutritional status. Even children with only mild feeding dysfunction, requiring chopped or mashed foods, may be at risk for poor nutritional status. Parental report of feeding dysfunction with a structured questionnaire may be useful in screening children for nutritional risk. J Am Diet Assoc. 2002; 102:361–368, 373.

The Design and Analysis of Experiments

Abstract: THE DESIGN AND ANALYSIS OF EXPERIMENTS. By Oscar Kempthorne. New York, John Wiley and Sons, Inc., 1952. 631 pp. $8.50. This book by a teacher of statistics (as well as a consultant for \"experimenters\") is a comprehensive study of the philosophical background for the statistical design of experiment. It is necessary to have some facility with algebraic notation and manipulation to be able to use the volume intelligently. The problems are presented from the theoretical point of view, without such practical examples as would be helpful for those not acquainted with mathematics. The mathematical justification for the techniques is given. As a somewhat advanced treatment of the design and analysis of experiments, this volume will be interesting and helpful for many who approach statistics theoretically as well as practically. With emphasis on the \"why,\" and with description given broadly, the author relates the subject matter to the general theory of statistics and to the general problem of experimental inference. MARGARET J. ROBERTSON

Standards of Medical Care in Diabetes

Abstract: XI. STRATEGIES FOR IMPROVING DIABETES CARE D iabetes is a chronic illness that requires continuing medical care and patient self-management education to prevent acute complications and to reduce the risk of long-term complications. Diabetes care is complex and requires that many issues, beyond glycemic control, be addressed. A large body of evidence exists that supports a range of interventions to improve diabetes outcomes. These standards of care are intended to provide clinicians, patients, researchers, payors, and other interested individuals with the components of diabetes care, treatment goals, and tools to evaluate the quality of care. While individual preferences, comorbidities, and other patient factors may require modification of goals, targets that are desirable for most patients with diabetes are provided. These standards are not intended to preclude more extensive evaluation and management of the patient by other specialists as needed. For more detailed information, refer to Bode (Ed.): Medical Management of Type 1 Diabetes (1), Burant (Ed): Medical Management of Type 2 Diabetes (2), and Klingensmith (Ed): Intensive Diabetes Management (3). The recommendations included are diagnostic and therapeutic actions that are known or believed to favorably affect health outcomes of patients with diabetes. A grading system (Table 1), developed by the American Diabetes Association (ADA) and modeled after existing methods, was utilized to clarify and codify the evidence that forms the basis for the recommendations. The level of evidence that supports each recommendation is listed after each recommendation using the letters A, B, C, or E.

Guidelines for the Early Management of Patients With Acute Ischemic Stroke A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association

Abstract: Background and Purpose—The authors present an overview of the current evidence and management recommendations for evaluation and treatment of adults with acute ischemic stroke. The intended audienc...

Acute Kidney Injury Network: report of an initiative to improve outcomes in acute kidney injury

Abstract: Acute kidney injury (AKI) is a complex disorder for which currently there is no accepted definition. Having a uniform standard for diagnosing and classifying AKI would enhance our ability to manage these patients. Future clinical and translational research in AKI will require collaborative networks of investigators drawn from various disciplines, dissemination of information via multidisciplinary joint conferences and publications, and improved translation of knowledge from pre-clinical research. We describe an initiative to develop uniform standards for defining and classifying AKI and to establish a forum for multidisciplinary interaction to improve care for patients with or at risk for AKI. Members representing key societies in critical care and nephrology along with additional experts in adult and pediatric AKI participated in a two day conference in Amsterdam, The Netherlands, in September 2005 and were assigned to one of three workgroups. Each group's discussions formed the basis for draft recommendations that were later refined and improved during discussion with the larger group. Dissenting opinions were also noted. The final draft recommendations were circulated to all participants and subsequently agreed upon as the consensus recommendations for this report. Participating societies endorsed the recommendations and agreed to help disseminate the results. The term AKI is proposed to represent the entire spectrum of acute renal failure. Diagnostic criteria for AKI are proposed based on acute alterations in serum creatinine or urine output. A staging system for AKI which reflects quantitative changes in serum creatinine and urine output has been developed. We describe the formation of a multidisciplinary collaborative network focused on AKI. We have proposed uniform standards for diagnosing and classifying AKI which will need to be validated in future studies. The Acute Kidney Injury Network offers a mechanism for proceeding with efforts to improve patient outcomes.