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Promoting Adherence And Retention To Clinical Trials In Special Populations: A Women's Health Initiative Workshop, Sara Wilcox, Sally Shumaker, Deborah Bowen, Michelle Naughton, Milagros Rosal, Shari Ludlam, Elizabeth Dugan, Julie Hunt, Stephanie Stevens

Elizabeth Dugan

This paper describes a Women's Health Initiative workshop on promoting adherence and retention in randomized clinical trials among ethnic minority women, participants of lower socioeconomic status, and older women. Workshop objectives were: (1) to increase knowledge of demographic and cultural characteristics of diverse groups, (2) to increase awareness of how diversity can affect interactions in clinical research, (3) to explore how research staff behavior can influence adherence and retention, and (4) to increase knowledge of strategies to enhance adherence and retention in special populations. The workshop emphasized the importance of understanding beliefs, values, and experiences that are common in diverse …

Development Of Abbreviated Measures To Assess Patient Trust In A Physician, A Health Insurer, And The Medical Profession, Elizabeth Dugan, Felicia Trachtenberg, Mark Hall

Elizabeth Dugan

BACKGROUND: Despite the recent proliferation in research on patient trust, it is seldom a primary outcome, and is often a peripheral area of interest. The length of our original scales to measure trust may limit their use because of the practical needs to minimize both respondent burden and research cost. The objective of this study was to develop three abbreviated scales to measure trust in: (1) a physician, (2) a health insurer, and (3) the medical profession. METHODS: Data from two samples were used. The first was a telephone survey of English-speaking adults in the United States (N = 1117) …

Patient Education About Anticoagulant Medication: Is Narrative Evidence Or Statistical Evidence More Effective?, Kathleen Mazor, Joann Baril, Elizabeth Dugan, Frederick Spencer, Pamela Burgwinkle, Jerry Gurwitz

Elizabeth Dugan

OBJECTIVE: To determine the relative impact of incorporating narrative evidence, statistical evidence or both into patient education about warfarin, a widely used oral anticoagulant medication.

METHODS: 600 patients receiving anticoagulant therapy were randomly assigned to view one of three versions of a video depicting a physician-patient encounter where anticoagulation treatment was discussed, or usual care (no video). The videos differed in whether the physician used narrative evidence (patient anecdotes), statistical evidence, or both to highlight key information. 317 patients completed both the baseline and post-test questionnaires. Questions assessed knowledge, beliefs and adherence to medication and laboratory monitoring regimens.

RESULTS: All …

Nitric Oxide-Mediated Inhibition Of Hdm2-P53 Binding, Christopher Schonhoff, Marie-Claire Daou, Stephen Jones, Celia Schiffer, Alonzo Ross

Celia A. Schiffer

It has become increasingly evident that nitric oxide exerts its effects, in part, by S-nitrosylation of cysteine residues. We tested in vitro whether nitric oxide may indirectly control p53 by S-nitrosylation and inactivation of the p53 negative regulator, Hdm2. Treatment of Hdm2 with a nitric oxide donor inhibits Hdm2-p53 binding, a critical step in Hdm2 regulation of p53. The presence of excess amounts of cysteine or dithiothreitol blocks this inhibition of binding. Moreover, nitric oxide inhibition of Hdm2-p53 binding was found to be reversible. Sulfhydryl sensitivity and reversibility are consistent with nitrosylation. Finally, we have identified a critical cysteine residue …

Association Of A Novel Human Immunodeficiency Virus Type 1 Protease Substrate Cleft Mutation, L23i, With Protease Inhibitor Therapy And In Vitro Drug Resistance, Elizabeth Johnston, Mark Winters, Soo-Yon Rhee, Thomas Merigan, Celia Schiffer, Robert Shafer

Celia A. Schiffer

We observed a previously uncharacterized mutation in the protease substrate cleft, L23I, in 31 of 4,303 persons undergoing human immunodeficiency virus type 1 genotypic resistance testing. In combination with V82I, L23I was associated with a sevenfold reduction in nelfinavir susceptibility and a decrease in replication capacity. In combination with other drug resistance mutations, L23I was associated with multidrug resistance and a compensatory increase in replication capacity.

Co-Evolution Of Nelfinavir-Resistant Hiv-1 Protease And The P1-P6 Substrate, Madhavi Kolli, Stephane Lastere, Celia Schiffer

Celia A. Schiffer

The selective pressure of the competitive protease inhibitors causes both HIV-1 protease and occasionally its substrates to evolve drug resistance. We hypothesize that this occurs particularly in substrates that protrude beyond the substrate envelope and contact residues that mutate in response to a particular protease inhibitor. To validate this hypothesis, we analyzed substrate and protease sequences for covariation. Using the chi2 test, we show a positive correlation between the nelfinavir-resistant D30N/N88D protease mutations and mutations at the p1-p6 cleavage site as compared to the other cleavage sites. Both nelfinavir and the substrate p1-p6 protrude beyond the substrate envelope and contact …

Substrate Shape Determines Specificity Of Recognition For Hiv-1 Protease: Analysis Of Crystal Structures Of Six Substrate Complexes, Moses Prabu-Jeyabalan, Ellen Nalivaika, Celia Schiffer

Celia A. Schiffer

The homodimeric HIV-1 protease is the target of some of the most effective antiviral AIDS therapy, as it facilitates viral maturation by cleaving ten asymmetric and nonhomologous sequences in the Gag and Pol polyproteins. Since the specificity of this enzyme is not easily determined from the sequences of these cleavage sites alone, we solved the crystal structures of complexes of an inactive variant (D25N) of HIV-1 protease with six peptides that correspond to the natural substrate cleavage sites. When the protease binds to its substrate and buries nearly 1000 A2 of surface area, the symmetry of the protease is broken, …

Toward The Design Of Mutation-Resistant Enzyme Inhibitors: Further Evaluation Of The Substrate Envelope Hypothesis, Visvaldas Kairys, Michael Gilson, Viney Lather, Celia Schiffer, Miguel Fernandes

Celia A. Schiffer

Previous studies have shown the usefulness of the substrate envelope concept in the analysis and prediction of drug resistance profiles for human immunodeficiency virus protease mutants. This study tests its applicability to several other therapeutic targets: Abl kinase, chitinase, thymidylate synthase, dihydrofolate reductase, and neuraminidase. For the targets where many (> or =6) mutation data are available to compute the average mutation sensitivity of inhibitors, the total volume of an inhibitor molecule that projects outside the substrate envelope V(out), is found to correlate with average mutation sensitivity. Analysis of a locally computed volume suggests that the same correlation would hold …

Design Of Hiv-1 Protease Inhibitors Active On Multidrug-Resistant Virus, Dominique Surleraux, Herman De Kock, Wim Verschueren, Geert Pille, Louis Maes, Anik Peeters, Sandrine Vendeville, Sandra De Meyer, Hilde Azijn, Rudi Pauwels, Marie-Pierre De Bethune, Nancy King, Moses Prabu-Jeyabalan, Celia Schiffer, Piet Wigerinck

Celia A. Schiffer

On the basis of structural data gathered during our ongoing HIV-1 protease inhibitors program, from which our clinical candidate TMC114 9 was selected, we have discovered new series of fused heteroaromatic sulfonamides. The further extension into the P2' region was aimed at identifying new classes of compounds with an improved broad spectrum activity and acceptable pharmacokinetic properties. Several of these compounds display an exceptional broad spectrum activity against a panel of highly cross-resistant mutants. Certain members of these series exhibit favorable pharmacokinetic profiles in rat and dog. Crystal structures and molecular modeling were used to rationalize the broad spectrum profile …

Pten Enters The Nucleus By Diffusion, Fenghua Liu, Stefan Wagner, Robert Campbell, Jeffrey Nickerson, Celia Schiffer, Alonzo Ross

Celia A. Schiffer

Despite much evidence for phosphatidylinositol phosphate (PIP)-triggered signaling pathways in the nucleus, there is little understanding of how the levels and activities of these proteins are regulated. As a first step to elucidating this problem, we determined whether phosphatase and tensin homolog deleted on chromosome 10 (PTEN) enters the nucleus by passive diffusion or active transport. We expressed various PTEN fusion proteins in tsBN2, HeLa, LNCaP, and U87MG cells and determined that the largest PTEN fusion proteins showed little or no nuclear localization. Because diffusion through nuclear pores is limited to proteins of 60,000 Da or less, this suggests that …

Dynamics Of Preferential Substrate Recognition In Hiv-1 Protease: Redefining The Substrate Envelope, Aysegul Ozen, Turkan Haliloglu, Celia Schiffer

Celia A. Schiffer

Human immunodeficiency virus type 1 (HIV-1) protease (PR) permits viral maturation by processing the gag and gag-pro-pol polyproteins. HIV-1 PR inhibitors (PIs) are used in combination antiviral therapy but the emergence of drug resistance has limited their efficacy. The rapid evolution of HIV-1 necessitates consideration of drug resistance in novel drug design. Drug-resistant HIV-1 PR variants no longer inhibited efficiently, continue to hydrolyze the natural viral substrates. Though highly diverse in sequence, the HIV-1 PR substrates bind in a conserved three-dimensional shape we termed the substrate envelope. Earlier, we showed that resistance mutations arise where PIs protrude beyond the substrate …

N88d Facilitates The Co-Occurrence Of D30n And L90m And The Development Of Multidrug Resistance In Hiv Type 1 Protease Following Nelfinavir Treatment Failure, Yumi Mitsuya, Mark Winters, W. Jeffrey Fessel, Soo-Yon Rhee, Leo Hurley, Michael Horberg, Celia Schiffer, Andrew Zolopa, Robert Shafer

Celia A. Schiffer

Nelfinavir was once one of the most commonly used protease inhibitors (PIs). To investigate the genetic mechanisms of multidrug resistance in protease isolates with the primary nelfinavir resistance mutation D30N, we analyzed patterns of protease mutations in 582 viruses with D30N from 460 persons undergoing HIV-1 genotypic resistance testing at Stanford University Hospital from 1997 to 2005. Three patterns of mutational associations were identified. First, D30N was positively associated with N88D but negatively associated with N88S. Second, D30N and L90M were negatively associated except in the presence of N88D, which facilitated the co-occurrence of D30N and L90M. Third, D30N+N88D+L90M formed …

Design And Synthesis Of Hiv-1 Protease Inhibitors Incorporating Oxazolidinones As P2/P2' Ligands In Pseudosymmetric Dipeptide Isosteres, G. S. Kiran Kumar Reddy, Akbar Ali, Madhavi Nalam, Saima Anjum, Hong Cao, Robin Nathans, Celia Schiffer, Tariq Rana

Celia A. Schiffer

A series of novel HIV-1 protease inhibitors based on two pseudosymmetric dipeptide isosteres have been synthesized and evaluated. The inhibitors were designed by incorporating N-phenyloxazolidinone-5-carboxamides into the hydroxyethylene and (hydroxyethyl)hydrazine dipeptide isosteres as P2 and P2' ligands. Compounds with (S)-phenyloxazolidinones attached at a position proximal to the central hydroxyl group showed low nM inhibitory activities against wild-type HIV-1 protease. Selected compounds were further evaluated for their inhibitory activities against a panel of multidrug-resistant protease variants and for their antiviral potencies in MT-4 cells. The crystal structures of lopinavir (LPV) and two new inhibitors containing phenyloxazolidinone-based ligands in complex with wild-type …

Replacement Of The P1 Amino Acid Of Human Immunodeficiency Virus Type 1 Gag Processing Sites Can Inhibit Or Enhance The Rate Of Cleavage By The Viral Protease, Steve Pettit, Gavin Henderson, Celia Schiffer, Ronald Swanstrom

Celia A. Schiffer

Processing of the human immunodeficiency virus type 1 (HIV-1) Gag precursor is highly regulated, with differential rates of cleavage at the five major processing sites to give characteristic processing intermediates. We examined the role of the P1 amino acid in determining the rate of cleavage at each of these five sites by using libraries of mutants generated by site-directed mutagenesis. Between 12 and 17 substitution mutants were tested at each P1 position in Gag, using recombinant HIV-1 protease (PR) in an in vitro processing reaction of radiolabeled Gag substrate. There were three sites in Gag (MA/CA, CA/p2, NC/p1) where one …

Point Mutants Of Ehec Intimin That Diminish Tir Recognition And Actin Pedestal Formation Highlight A Putative Tir Binding Pocket, Hui Liu, Padhma Radhakrishnan, Loranne Magoun, Moses Prabu-Jeyabalan, Kenneth Campellone, Pamela Savage, Feng He, Celia Schiffer, John Leong

Celia A. Schiffer

Attachment to host cells by enterohaemorrhagic Escherichia coli (EHEC) is associated with the formation of a highly organized cytoskeletal structure containing filamentous actin, termed an attaching and effacing (AE) lesion. Intimin, an outer membrane protein of EHEC, is required for the formation of AE lesions, as is Tir, a bacterial protein that is translocated into the host cell to function as a receptor for intimin. We established a yeast two-hybrid assay for intimin-Tir interaction and, after random mutagenesis, isolated 24 point mutants in intimin, which disrupted Tir recognition in this system. Analysis of 11 point mutants revealed a correlation between …

Structural And Thermodynamic Basis For The Binding Of Tmc114, A Next-Generation Human Immunodeficiency Virus Type 1 Protease Inhibitor, Nancy King, Moses Prabu-Jeyabalan, Ellen Nalivaika, Piet Wigerinck, Marie-Pierre De Bethune, Celia Schiffer

Celia A. Schiffer

TMC114, a newly designed human immunodeficiency virus type 1 (HIV-1) protease inhibitor, is extremely potent against both wild-type (wt) and multidrug-resistant (MDR) viruses in vitro as well as in vivo. Although chemically similar to amprenavir (APV), the potency of TMC114 is substantially greater. To examine the basis for this potency, we solved crystal structures of TMC114 complexed with wt HIV-1 protease and TMC114 and APV complexed with an MDR (L63P, V82T, and I84V) protease variant. In addition, we determined the corresponding binding thermodynamics by isothermal titration calorimetry. TMC114 binds approximately 2 orders of magnitude more tightly to the wt enzyme …

The Effect Of Clade-Specific Sequence Polymorphisms On Hiv-1 Protease Activity And Inhibitor Resistance Pathways, Rajintha Bandaranayake, Madhavi Kolli, Nancy King, Ellen Nalivaika, Annie Heroux, Junko Kakizawa, Wataru Sugiura, Celia Schiffer

Celia A. Schiffer

The majority of HIV-1 infections around the world result from non-B clade HIV-1 strains. The CRF01_AE (AE) strain is seen principally in Southeast Asia. AE protease differs by approximately 10% in amino acid sequence from clade B protease and carries several naturally occurring polymorphisms that are associated with drug resistance in clade B. AE protease has been observed to develop resistance through a nonactive-site N88S mutation in response to nelfinavir (NFV) therapy, whereas clade B protease develops both the active-site mutation D30N and the nonactive-site mutation N88D. Structural and biochemical studies were carried out with wild-type and NFV-resistant clade B …

Lack Of Synergy For Inhibitors Targeting A Multi-Drug-Resistant Hiv-1 Protease, Nancy King, Laurence Melnick, Moses Prabu-Jeyabalan, Ellen Nalivaika, Shiow-Shong Yang, Yun Gao, Xiaoyi Nie, Charles Zepp, Donald Heefner, Celia Schiffer

Celia A. Schiffer

The three-dimensional structures of indinavir and three newly synthesized indinavir analogs in complex with a multi-drug-resistant variant (L63P, V82T, I84V) of HIV-1 protease were determined to approximately 2.2 A resolution. Two of the three analogs have only a single modification of indinavir, and their binding affinities to the variant HIV-1 protease are enhanced over that of indinavir. However, when both modifications were combined into a single compound, the binding affinity to the protease variant was reduced. On close examination, the structural rearrangements in the protease that occur in the tightest binding inhibitor complex are mutually exclusive with the structural rearrangements …

Human Immunodeficiency Virus Type 1 Protease-Correlated Cleavage Site Mutations Enhance Inhibitor Resistance, Madhavi Kolli, Eric Stawiski, Colombe Chappey, Celia Schiffer

Celia A. Schiffer

Drug resistance is an important cause of antiretroviral therapy failure in human immunodeficiency virus (HIV)-infected patients. Mutations in the protease render the virus resistant to protease inhibitors (PIs). Gag cleavage sites also mutate, sometimes correlating with resistance mutations in the protease, but their contribution to resistance has not been systematically analyzed. The present study examines mutations in Gag cleavage sites that associate with protease mutations and the impact of these associations on drug susceptibilities. Significant associations were observed between mutations in the nucleocapsid-p1 (NC-p1) and p1-p6 cleavage sites and various PI resistance-associated mutations in the protease. Several patterns were frequently …

Discovery And Selection Of Tmc114, A Next Generation Hiv-1 Protease Inhibitor, Dominique Surleraux, Abdellah Tahri, Wim Verschueren, Geert Pille, Herman De Kock, Tim Jonckers, Anik Peeters, Sandra De Meyer, Hilde Azijn, Rudi Pauwels, Marie-Pierre De Bethune, Nancy King, Moses Prabu-Jeyabalan, Celia Schiffer, Piet Wigerinck

Celia A. Schiffer

The screening of known HIV-1 protease inhibitors against a panel of multi-drug-resistant viruses revealed the potent activity of TMC126 on drug-resistant mutants. In comparison to amprenavir, the improved affinity of TMC126 is largely the result of one extra hydrogen bond to the backbone of the protein in the P2 pocket. Modification of the substitution pattern on the phenylsulfonamide P2' substituent of TMC126 created an interesting SAR, with the close analogue TMC114 being found to have a similar antiviral activity against the mutant and the wild-type viruses. X-ray and thermodynamic studies on both wild-type and mutant enzymes showed an extremely high …

Time As A Catalyst For Tension In Nurse-Surgeon Communication, Sherry Espin, Lorelei Lingard

Lorelei Lingard

Carefully studying communication patterns between nurses and surgeons questions popular stereotypes about OR discourse and expands educators' understanding of the factors that motivate team communication, patterns that are habitual among team members, and issues that act as catalysts for tension. This study examines the nature of communication between perioperative nurses and surgeons and identifies patterns and sites of tension. Researchers observed 128 hours of interaction between nurses and surgeons in four surgical divisions at one teaching hospital in Ontario, Canada. Field notes were read, coded, and analyzed independently. Results showed that higher tension in nurse-surgeon communication clusters around particular themes, …

Antibiotics For Bronchiolitis In Children, Geoffrey Spurling, Jenny Doust, Chris Del Mar, Lars Ericksson

Jenny Doust

Background: Bronchiolitis is a serious, potentially life-threatening respiratory illness commonly affecting babies. It is often caused by respiratory syncytial virus (RSV). Antibiotics are not recommended for bronchiolitis unless there is concern about complications such as secondary bacterial pneumonia or respiratory failure. Nevertheless, they are used at rates of 34% to 99% in uncomplicated cases. Objectives: To evaluate the effectiveness of antibiotics for bronchiolitis. Search strategy: We searched the Cochrane Central Register of Controlled Trials (CENTRAL 2010, issue 4), which includes the Cochrane Acute Respiratory Infection Group’s Specialised Register, and the Database of Abstracts of Reviews of Effects, MEDLINE (January 1966 …

Novel Interactors And A Role For Supervillin In Early Cytokinesis, Tara Smith, Zhiyou Fang, Elizabeth Luna

Elizabeth J. Luna

Supervillin, the largest member of the villin/gelsolin/flightless family, is a peripheral membrane protein that regulates each step of cell motility, including cell spreading. Most known interactors bind within its amino (N)-terminus. We show here that the supervillin carboxy (C)-terminus can be modeled as supervillin-specific loops extending from gelsolin-like repeats plus a villin-like headpiece. We have identified 27 new candidate interactors from yeast two-hybrid screens. The interacting sequences from 12 of these proteins (BUB1, EPLIN/LIMA1, FLNA, HAX1, KIF14, KIFC3, MIF4GD/SLIP1, ODF2/Cenexin, RHAMM, STARD9/KIF16A, Tks5/SH3PXD2A, TNFAIP1) co-localize with and mis-localize EGFP-supervillin in mammalian cells, suggesting associations in vivo. Supervillin-interacting sequences within BUB1, …

Alcohol And Hepatitis C Virus--Interactions In Immune Dysfunctions And Liver Damage, Gyongyi Szabo, Jack Wands, Ahment Eken, Natalia Osna, Steven Weinman, Keigo Machida, Joe Wang

Gyongyi Szabo

Hepatitis C virus infection affects 170 million people worldwide, and the majority of individuals exposed to HCV develop chronic hepatitis leading to progressive liver damage, cirrhosis, and hepatocellular cancer. The natural history of HCV infection is influenced by genetic and environmental factors of which chronic alcohol use is an independent risk factor for cirrhosis in HCV-infected individuals. Both the hepatitis C virus and alcohol damage the liver and result in immune alterations contributing to both decreased viral clearance and liver injury. This review will capture the major components of the interactions between alcohol and HCV infection to provide better understanding …

Factors That Determine The Development And Progression Of Gastroesophageal Varices In Patients With Chronic Hepatitis C, Robert Fontana, Arun Sanyal, Marc Ghany, William Lee, Andrea Reid, Deepa Naishadham, Gregory Everson, Jeffrey Kahn, Adrian Di Bisceglie, Gyongyi Szabo, Timothy Morgan, James Everhart

Gyongyi Szabo

BACKGROUND and AIMS: We aimed to identify the incidence and predictors of de novo gastroesophageal variceal formation and progression in a large cohort of patients with chronic hepatitis C and advanced fibrosis. METHODS: All participants in the Hepatitis C Antiviral Long-Term Treatment against Cirrhosis Trial were offered an endoscopy before treatment and again after 4 years. Patients with varices at baseline also had an endoscopy at 2 years. Baseline laboratory and clinical parameters were analyzed as predictors of de novo variceal formation and variceal progression. RESULTS: De novo varices developed in 157 of the 598 (26.2%) patients. Most of the …

The 40th Anniversary Of The National Institute On Alcoholism And Alcohol Abuse: The Impact On Liver Disease, Gyongyi Szabo

Gyongyi Szabo

No abstract provided.

Alcohol Exposure As A Risk Factor For Adverse Outcomes In Elective Surgery, Bharath Nath, Youfu Li, James Carroll, Gyongyi Szabo, Jennifer Tseng, Shimul Shah

Gyongyi Szabo

BACKGROUND AND AIMS: Alcohol consumption is a well-documented determinant of adverse perioperative outcome. We sought to determine the effect of active alcohol consumption following elective surgery. METHODS: We queried discharge records from the American College of Surgeons' National Surgical Quality Improvement Program (NSQIP, 2005-2007) for all elective adult admissions. The 7,631 (2.5%) patients with documented alcohol use (active alcohol use of at least two drinks per day within 2 weeks of surgery; ETOH use) underwent elective surgery; 301,994 (97.5%) patients denied ETOH use. Multivariate analysis was performed with adjustments for demographic and comorbid factors. Primary outcome measures included length of …

Declining Length Of Stay For Patients Hospitalized With Ami: Impact On Mortality And Readmissions, Jane Saczynski, Darleen Lessard, Frederick Spencer, Jerry Gurwitz, Joel Gore, Jorge Yarzebski, Robert Goldberg

Jorge L. Yarzebski

BACKGROUND: Length of hospital stay after acute myocardial infarction decreased significantly in the 1980s and 1990s. Whether length of stay has continued to decrease during the 2000s, and the impact of decreasing length of stay on rehospitalization and mortality, is unclear. We describe decade-long (1995-2005) trends in length of stay after acute myocardial infarction, and examine whether declining length of stay has impacted early rehospitalization and postdischarge mortality in a population-based sample of hospitalized patients.

METHODS: The study sample consisted of 4184 patients hospitalized with acute myocardial infarction in a central New England metropolitan area during 6 annual periods (1995, …

Management And Outcomes Of Renal Disease And Acute Myocardial Infarction, Paul Santolucito, Dennis Tighe, David Mcmanus, Jorge Yarzebski, Darleen Lessard, Joel Gore, Robert Goldberg

Jorge L. Yarzebski

BACKGROUND: Contemporary trends in the management and outcomes of chronic kidney disease patients who develop an acute myocardial infarction have not been adequately described, particularly from the more generalizable perspective of a population-based investigation. METHODS: The study population consisted of 6219 residents of the Worcester, Massachusetts, metropolitan area who were hospitalized with acute myocardial infarction in 6 annual periods between 1995 and 2005. Patients were categorized as having preserved kidney function (n=3154), mild to moderate chronic kidney disease (n=2313), or severe chronic kidney disease (n=752) at the time of hospital admission. RESULTS: Patients with chronic kidney disease were more likely …