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Design and Methods for a Comparative Effectiveness Pilot Study: Virtual World vs. Face-to-Face Diabetes Self-Management

Thu, 02/27/2014 - 2:22pm

BACKGROUND: Type 2 diabetes (diabetes) is a serious threat to public health in the United States and disproportionally affects many racial/ethnic minority groups, including African Americans. Limited access to treatment and high attrition rates further contribute to health disparities in diabetes-related morbidity and mortality among minorities. Greater opportunities for increasing access and decreasing barriers to treatment are needed. Technology-based interventions have potential for accomplishing this goal but evidence of feasibility and potential effectiveness is lacking, especially for populations that traditionally have limited educational attainment and low computer literacy.

OBJECTIVE: This paper describes the design and methods of a pilot randomized clinical trial that will compare the feasibility and potential efficacy of delivering a diabetes self-management intervention via a virtual world vs. a face-to-face format.

METHODS: Study participants (n=100) will be African American women with uncontrolled type 2 diabetes recruited from primary care practices and affiliated health centers at a large safety net hospital in Massachusetts. Participants will be randomized into a virtual world-based (VW) intervention condition or a face-to-face control condition. Both conditions provide the same theory-based curriculum and equivalent exposure to the self-management program (eight group sessions), and both will be delivered by a single intervention team (a dietitian and a diabetes educator). Assessments will be conducted at baseline and 4 months. Feasibility will be determined by evaluating the degree to which participants engage in the VW-based intervention compared to face to face (number of sessions completed). Potential efficacy will be determined by comparing change in physiological (glycemic control) and behavioral (self-reported dietary intake, physical activity, blood glucose self-monitoring, and medication adherence) outcomes between the experimental and control groups.

RESULTS: The primary outcomes of interest are feasibility of the VW intervention and its potential efficacy on glucose control and diabetes self-management behaviors, compared to the face-to-face condition. Analysis will use a two-sample Kolmogorov-Smirnov test for changes in variable distribution. P values will be calculated using binomial tests for proportions and t tests for continuous variables.

CONCLUSIONS: If the intervention is found to be feasible and promising, it will be tested in a larger RCT.

Awareness of diabetes risk factors and prevention strategies among a sample of low-income Latinos with no known diagnosis of diabetes

Thu, 02/27/2014 - 2:22pm

PURPOSE: This study assessed awareness of type 2 diabetes risk and severity, perceived risk factors, knowledge of diabetes prevention strategies, and challenges of and opportunities for prevention among low-income Latinos in Lawrence, Massachusetts.

METHODS: Qualitative research design. Latinos with no known diagnosis of diabetes participated in 4 focus groups, conducted in Spanish, which were recorded and transcribed for systematic analysis.

RESULTS: The sample, (N = 41) was largely female (85%) with a wide age range (22-76 years), most (71%) had an educational level of high school or less, and less than half (46%) were employed. Participants had basic knowledge of diabetes, but gaps were apparent. Many perceived family history of diabetes, poor diet, emotional distress, and stress associated with the United States as risk factors for diabetes. There was little or no awareness of risk associated with Latino ethnicity, gestational diabetes, hypertension, lipid abnormalities, or obesity. Few cited physical activity or weight loss as diabetes prevention strategies. More than half the participants perceived themselves at low risk for diabetes.

CONCLUSIONS: This Latino sample had limited knowledge of diabetes risk factors and lifestyle changes that can prevent or delay diabetes onset. Insights for intervening for diabetes prevention are offered.

Evaluation of the American Heart Association cardiovascular disease prevention guideline for women

Thu, 02/27/2014 - 2:22pm

BACKGROUND: The 2007 update to the American Heart Association (AHA) guidelines for cardiovascular disease prevention in women recommend a simplified approach to risk stratification. We assigned Women's Health Initiative participants to risk categories as described in the guideline and evaluated clinical event rates within and between strata.

METHODS AND RESULTS: The Women's Health Initiative enrolled 161 808 women ages 50 to 79 years and followed them prospectively for 7.8 years (mean). Applying the 2007 AHA guideline categories, 11% of women were high risk, 72% at-risk, and 4% at optimal risk; 13% of women did not fall into any category, that is, lacked risk factors but did not adhere to a healthy lifestyle (moderate intensity exercise for 30 minute most days and 20% (area under receiver operating characteristic curve for Framingham risk, 0.724; for AHA risk, 0.664; P<0.0001).

CONCLUSIONS: Risk stratification as proposed in the 2007 AHA guideline is simple, accessible to patients and providers, and identifies cardiovascular risk with accuracy similar to that of the current Framingham algorithm.

Clinical Trial Registration- clinicaltrials.gov. Identifier: NCT00000611.

Optimism, cynical hostility, and incident coronary heart disease and mortality in the Women's Health Initiative

Thu, 02/27/2014 - 2:22pm

BACKGROUND: Trait optimism (positive future expectations) and cynical, hostile attitudes toward others have not been studied together in relation to incident coronary heart disease (CHD) and mortality in postmenopausal women.

METHODS AND RESULTS: Participants were 97 253 women (89 259 white, 7994 black) from the Women's Health Initiative who were free of cancer and cardiovascular disease at study entry. Optimism was assessed by the Life Orientation Test-Revised and cynical hostility by the cynicism subscale of the Cook Medley Questionnaire. Cox proportional hazard models produced adjusted hazard ratios (AHRs) for incident CHD (myocardial infarction, angina, percutaneous coronary angioplasty, or coronary artery bypass surgery) and total mortality (CHD, cardiovascular disease, or cancer related) over approximately 8 years. Optimists (top versus bottom quartile ["pessimists"]) had lower age-adjusted rates (per 10 000) of CHD (43 versus 60) and total mortality (46 versus 63). The most cynical, hostile women (top versus bottom quartile) had higher rates of CHD (56 versus 44) and total mortality (63 versus 46). Optimists (versus pessimists) had a lower hazard of CHD (AHR 0.91, 95% CI 0.83 to 0.99), CHD-related mortality (AHR 0.70, 95% CI 0.55 to 0.90), cancer-related mortality (blacks only; AHR 0.56, 95% CI 0.35 to 0.88), and total mortality (AHR 0.86, 95% CI 0.79 to 0.93). Most (versus least) cynical, hostile women had a higher hazard of cancer-related mortality (AHR 1.23, 95% CI 1.09 to 1.40) and total mortality (AHR 1.16, 95% CI 1.07 to 1.27; this effect was pronounced in blacks). Effects of optimism and cynical hostility were independent.

CONCLUSIONS: Optimism and cynical hostility are independently associated with important health outcomes in black and white women. Future research should examine whether interventions designed to change attitudes would lead to altered risk.

A collaborative care model to improve access to pediatric mental health services

Wed, 02/26/2014 - 11:12am

To examine if an innovative collaborative care model known as Targeted Child Psychiatric Services designed for primary care pediatricians (PCPs) and child psychiatrists (1) was associated with improved access to child psychiatry services, (2) had the potential to identify optimal care settings for pediatric mental health care and (3) examined if pediatricians appeared as likely to accept children back into their practices at discharge from TCPS depending upon diagnostic category, controlling for severity of illness and function. The diagnostic classes examined were ADHD (39%), depression (31%) and anxiety (13%). This prospective cohort design study collected medical records of 329 children referred to TCPS by 139 PCPs. To detect the likelihood of return to referring pediatricians for follow-up care at discharge from TCPS, we employed logistic regression models. Mean age was 12.3 (SD = 4.0); 43% were female. Ninety-three percent of parents complied with pediatricians' recommendations to have their child assessed by a child psychiatrist. A total of 28.0% of referrals returned to PCPs for follow-up care; the remainder were followed in mental health. Regression findings indicated that children with major depression (OR = 7.5) or anxiety disorders (OR = 5.1) were less likely to return to PCPs compared to ADHD even though severity of psychiatric illness and functional levels did not differ across diagnostic groups. Families widely accepted pediatricians' recommendations for referral to child psychiatrists. Depression and anxiety were strong correlates of retention in mental health settings at discharge from TCPS though children with these disorders appeared to be no more severely ill or functionally limited than peers with ADHD. These children possibly could be managed in a less intensive and expensive primary care treatment setting that could access mental health specialty services as needed in a collaborative model of care. TCPS is contrasted with the well-known collaborative model for adult depression in primary care. TCPS could serve as a feasible model of care that addresses the daunting barriers in accessing pediatric mental health services.

Differential regulation of G protein alpha subunit trafficking by mono- and polyubiquitination

Tue, 02/25/2014 - 10:41am

Previously we used mass spectrometry to show that the yeast G protein alpha subunit Gpa1 is ubiquitinated at Lys-165, located within a subdomain not present in other G alpha proteins (Marotti, L. A., Jr., Newitt, R., Wang, Y., Aebersold, R., and Dohlman, H. G. (2002) Biochemistry 41, 5067-5074). Here we describe the functional role of Gpa1 ubiquitination. We find that Gpa1 expression is elevated in mutants deficient in either proteasomal or vacuolar protease function. Vacuolar protease pep4 mutants accumulate monoubiquitinated Gpa1, and much of the protein is localized within the vacuolar compartment. In contrast, proteasome-defective rpt6/cim3 mutants accumulate polyubiquitinated Gpa1, and in this case the protein exhibits cytoplasmic localization. Cells that lack Ubp12 ubiquitin-processing protease activity accumulate both mono- and polyubiquitinated forms of Gpa1. In this case, Gpa1 accumulates in both the cytoplasm and vacuole. Finally, a Gpa1 mutant that lacks the ubiquitinated subdomain remains unmodified and is predominantly localized at the plasma membrane. These data reveal a strong relationship between the extent of ubiquitination and trafficking of the G protein alpha subunit to its site of degradation.

Coactivation of G protein signaling by cell-surface receptors and an intracellular exchange factor

Tue, 02/25/2014 - 10:41am

G protein-coupled receptors (GPCRs) mediate responses to a broad range of chemical and environmental signals. In yeast, a pheromone-binding GPCR triggers events leading to the fusion of haploid cells. In general, GPCRs function as guanine-nucleotide exchange factors (GEFs); upon agonist binding, the receptor induces a conformational change in the G protein alpha subunit, resulting in exchange of guanine diphosphate (GDP) for guanine triphosphate (GTP) and in signal initiation. Signaling is terminated when GTP is hydrolyzed to GDP [1]. This well-established paradigm has in recent years been revised to include new components that rates of GDP release, GTP binding [2-8], and GTP hydrolysis[9, 10]. Here we report the discovery of a nonreceptor GEF, Arr4. Like receptors, Arr4 binds directly to the G protein,accelerates guanine-nucleotide exchange, and stabilizes the nucleotide-free state of the a subunit. Moreover, Arr4 promotes G protein-dependent cellular responses, including mitogen-activated protein kinase (MAPK) phosphorylation,new-gene transcription, and mating. In contrast to knownGPCRs, however, Arr4 is not a transmembrane receptor,but rather a soluble intracellular protein. Our data suggest that intracellular proteins function in cooperation with mating pheromones to amplify G protein signaling, thereby leading to full pathway activation.

G Protein Mono-ubiquitination by the Rsp5 Ubiquitin Ligase

Tue, 02/25/2014 - 10:41am

Emerging evidence suggests that ubiquitination serves as a protein trafficking signal in addition to its well characterized role in promoting protein degradation. The yeast G protein alpha subunit Gpa1 represents a rare example of a protein that undergoes both mono- and poly-ubiquitination. Whereas mono-ubiquitinated Gpa1 is targeted to the vacuole, poly-ubiquitinated Gpa1 is directed instead to the proteasome. Here we investigate the structural requirements for mono- and poly-ubiquitination of Gpa1. We find that variants of Gpa1 engineered to be unstable are more likely to be poly-ubiquitinated and less likely to be mono-ubiquitinated. In addition, mutants that cannot be myristoylated are no longer mono-ubiquitinated but are still polyubiquitinated. Finally, we show that the ubiquitin ligase Rsp5 is necessary for Gpa1 mono-ubiquitination in vivo and that the purified enzyme is sufficient to catalyze Gpa1 mono-ubiquitination in vitro. Taken together, these data indicate that mono- and poly-ubiquitination have distinct enzyme and substrate recognition requirements; whereas poly-ubiquitination targets misfolded protein for degradation, a distinct ubiquitination apparatus targets the fully mature, fully myristoylated G protein for mono-ubiquitination and delivery to the vacuole.

Combined experimental and computational analysis of DNA damage signaling reveals context-dependent roles for Erk in apoptosis and G1/S arrest after genotoxic stress

Tue, 02/25/2014 - 10:41am

Following DNA damage, cells display complex multi-pathway signaling dynamics that connect cell-cycle arrest and DNA repair in G1, S, or G2/M phase with phenotypic fate decisions made between survival, cell-cycle re-entry and proliferation, permanent cell-cycle arrest, or cell death. How these phenotypic fate decisions are determined remains poorly understood, but must derive from integrating genotoxic stress signals together with inputs from the local microenvironment. To investigate this in a systematic manner, we undertook a quantitative time-resolved cell signaling and phenotypic response study in U2OS cells receiving doxorubicin-induced DNA damage in the presence or absence of TNFalpha co-treatment; we measured key nodes in a broad set of DNA damage signal transduction pathways along with apoptotic death and cell-cycle regulatory responses. Two relational modeling approaches were then used to identify network-level relationships between signals and cell phenotypic events: a partial least squares regression approach and a complementary new technique which we term 'time-interval stepwise regression.' Taken together, the results from these analysis methods revealed complex, cytokine-modulated inter-relationships among multiple signaling pathways following DNA damage, and identified an unexpected context-dependent role for Erk in both G1/S arrest and apoptotic cell death following treatment with this commonly used clinical chemotherapeutic drug.

Sequential application of anticancer drugs enhances cell death by rewiring apoptotic signaling networks

Tue, 02/25/2014 - 10:40am

Crosstalk and complexity within signaling pathways and their perturbation by oncogenes limit component-by-component approaches to understanding human disease. Network analysis of how normal and oncogenic signaling can be rewired by drugs may provide opportunities to target tumors with high specificity and efficacy. Using targeted inhibition of oncogenic signaling pathways, combined with DNA-damaging chemotherapy, we report that time-staggered EGFR inhibition, but not simultaneous coadministration, dramatically sensitizes a subset of triple-negative breast cancer cells to genotoxic drugs. Systems-level analysis-using high-density time-dependent measurements of signaling networks, gene expression profiles, and cell phenotypic responses in combination with mathematical modeling-revealed an approach for altering the intrinsic state of the cell through dynamic rewiring of oncogenic signaling pathways. This process converts these cells to a less tumorigenic state that is more susceptible to DNA damage-induced cell death by reactivation of an extrinsic apoptotic pathway whose function is suppressed in the oncogene-addicted state.

The bromodomain protein Brd4 insulates chromatin from DNA damage signalling

Tue, 02/25/2014 - 10:40am

DNA damage activates a signalling network that blocks cell-cycle progression, recruits DNA repair factors and/or triggers senescence or programmed cell death. Alterations in chromatin structure are implicated in the initiation and propagation of the DNA damage response. Here we further investigate the role of chromatin structure in the DNA damage response by monitoring ionizing-radiation-induced signalling and response events with a high-content multiplex RNA-mediated interference screen of chromatin-modifying and -interacting genes. We discover that an isoform of Brd4, a bromodomain and extra-terminal (BET) family member, functions as an endogenous inhibitor of DNA damage response signalling by recruiting the condensin II chromatin remodelling complex to acetylated histones through bromodomain interactions. Loss of this isoform results in relaxed chromatin structure, rapid cell-cycle checkpoint recovery and enhanced survival after irradiation, whereas functional gain of this isoform compacted chromatin, attenuated DNA damage response signalling and enhanced radiation-induced lethality. These data implicate Brd4, previously known for its role in transcriptional control, as an insulator of chromatin that can modulate the signalling response to DNA damage.

Antidepressant augmentation using the N-methyl-D-aspartate antagonist memantine: a randomized, double-blind, placebo-controlled trial

Wed, 02/19/2014 - 12:52pm

OBJECTIVE: Intravenous N-methyl-d-aspartate (NMDA) antagonists have shown promising results in rapidly ameliorating depression symptoms, but placebo-controlled trials of oral NMDA antagonists as monotherapy have not observed efficacy. We conducted a randomized, double-blind, placebo-controlled trial of the NMDA antagonist memantine as an augmentation treatment for patients with DSM-IV major depressive disorder.

METHOD: Adult outpatients with major depressive disorder and partial response or nonresponse to their current antidepressant (as indicated by a 17-item Hamilton Depression Rating Scale score of >/= 16 at baseline) were randomized (from July 2006-December 2011) to add memantine (flexible dose 5-20 mg/d, with all memantine group participants reaching the dose of 20 mg/d) (n = 15) or placebo (n = 16) to their existing treatment for 8 weeks. The primary outcome, change in Montgomery-Asberg Depression Rating Score (MADRS), was evaluated with repeated-measures mixed effects models using last-observation-carried-forward methods. Secondary outcomes included other depression and anxiety rating scales, suicidal and delusional ideation, and other adverse effects.

RESULTS: 84% of participants completed the trial, including 93% of participants receiving memantine. Participants receiving memantine did not show a statistically or clinically significant change in MADRS scores compared to placebo, either over the entire study (beta = 0.133, favoring placebo, P = .74) or at study completion (week 8 mean [SD] MADRS score change = -7.13 [6.61] [memantine]; -7.25 [11.14] [placebo]; P = .97). A minimal to small effect size (comparing change to baseline variability) favoring placebo was observed (Cohen d = 0.19). Similarly, no substantial effect sizes favoring memantine nor statistically significant between-group differences were observed on secondary efficacy outcomes.

CONCLUSIONS: This trial did not detect significant statistical or effect size differences between memantine and placebo augmentation among nonresponders or poor responders to conventional antidepressants. While the small number of participants is a limitation, this study suggests memantine lacks substantial efficacy as an augmentation treatment for major depressive disorder.

TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT00344682.

A gender analysis of the study of pharmacotherapy of psychotic depression (STOP-PD): gender and age as predictors of response and treatment-associated changes in body mass index and metabolic measures

Wed, 02/19/2014 - 12:52pm

BACKGROUND: Gender differences exist in psychiatric disorders; however, gender has not been well studied in psychotic depression. This analysis of the largest clinical trial in psychotic depression examined the effects of age and gender on clinical characteristics and predictors of treatment outcome and treatment-associated changes in body mass index (BMI) and metabolic measures.

METHOD: Secondary analyses were performed on data from 259 subjects with major depressive disorder with psychotic features (DSM-IV-TR) aged 18-93 years in the double-blind randomized controlled trial of olanzapine plus sertraline versus olanzapine plus placebo for psychotic depression (Study of Pharmacotherapy of Psychotic Depression). Sociodemographic factors, clinical characteristics, treatment outcome, and treatment-associated changes in BMI and metabolic measures were analyzed by gender and age. Subjects were enrolled from December 2002 to June 2007.

RESULTS: Female gender was associated with divorced (χ(2)(1) = 5.3, P = .03) or widowed (χ(2)(1) = 8.1, P ≤ .01) marital status. Comorbid anxiety disorders were more common in women than in men (χ(2)(1) = 4.9, P = .03). Hallucinations (χ(2)(1) = 7.8, P = .005) and delusions with disorganization (t(257) = -2.10, P = .04) were significantly associated with female gender, as were higher cholesterol measures (χ(2)(1) = 7.15, P = .008). There were no significant interactions between treatment and gender in terms of change in BMI. Gender was not associated with treatment response.

DISCUSSION: This study is the first analysis of gender and age as predictors of treatment outcome and treatment-associated changes in BMI and metabolic adverse effects in psychotic depression. Gender differences exist in patients with psychotic depression, most notably with regard to the presence of hallucinations. Female gender was associated with metabolic measures. Future studies with larger sample sizes may detect small gender differences in treatment outcome and treatment-associated changes in BMI and metabolic measures in psychotic depression.

TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT00056472.

Complementary and alternative medicine therapies for perinatal depression

Wed, 02/19/2014 - 12:52pm

Complementary and alternative medicine therapies are increasingly sought out by people with psychiatric disorders. In this chapter, we review the evidence for several commonly used CAM therapies (i.e. omega-3 fatty acids, folate, S-adenosyl-methionine, St John's Wort, bright light therapy, exercise, massage, and acupuncture) in the treatment of perinatal depression. A number of these treatments may be reasonable to consider for women during pregnancy or postpartum, but the safety and efficacy of these relative to standard treatments must still be systematically determined. Evidence-based use of complementary and alternative medicine therapies treatments for perinatal depression is discussed. Adequately powered systematic studies are necessary to determine the role of complementary and alternative medicine therapies in the treatment of perinatal depression.

Pharmacotherapy for Mood Disorders in Pregnancy: A Review of Pharmacokinetic Changes and Clinical Recommendations for Therapeutic Drug Monitoring

Wed, 02/19/2014 - 12:52pm

OBJECTIVE: Pharmacotherapy for mood disorders during pregnancy is often complicated by pregnancy-related pharmacokinetic changes and the need for dose adjustments. The objectives of this review are to summarize the evidence for change in perinatal pharmacokinetics of commonly used pharmacotherapies for mood disorders, discuss the implications for clinical and therapeutic drug monitoring (TDM), and make clinical recommendations.

METHODS: The English-language literature indexed on MEDLINE/PubMed was searched for original observational studies (controlled and uncontrolled, prospective and retrospective), case reports, and case series that evaluated or described pharmacokinetic changes or TDM during pregnancy or the postpartum period.

RESULTS: Pregnancy-associated changes in absorption, distribution, metabolism, and elimination may result in lowered psychotropic drug levels and possible treatment effects, particularly in late pregnancy. Mechanisms include changes in both phase 1 hepatic cytochrome P450 and phase 2 uridine diphosphate glucuronosyltransferase enzyme activities, changes in hepatic and renal blood flow, and glomerular filtration rate. Therapeutic drug monitoring, in combination with clinical monitoring, is indicated for tricyclic antidepressants and mood stabilizers during the perinatal period.

CONCLUSIONS: Substantial pharmacokinetic changes can occur during pregnancy in a number of commonly used antidepressants and mood stabilizers. Dose increases may be indicated for antidepressants including citalopram, clomipramine, imipramine, fluoxetine, fluvoxamine, nortriptyline, paroxetine, and sertraline, especially late in pregnancy. Antenatal dose increases may also be needed for lithium, lamotrigine, and valproic acid because of perinatal changes in metabolism. Close clinical monitoring of perinatal mood disorders and TDM of tricyclic antidepressants and mood stabilizers are recommended.

Chemotherapy-Induced Myelopathy

Tue, 02/18/2014 - 1:36pm

Radiologically Isolated Syndrome: An Overview

Tue, 02/18/2014 - 1:36pm

The use of brain magnetic resonance imaging (MRI) for evaluation of neurological disorders has increased in the past two decades. This has led to an increased detection of incidental findings on brain MRI. The most common of these asymptomatic abnormalities are white matter lesions that are interpreted as demyelinating based on radiological criteria. However, in the absence of associated clinical symptoms suggestive of multiple sclerosis (MS), a definite diagnosis of MS cannot be made in patients with these incidental white matter lesions. These patients are now diagnosed as radiologically isolated syndrome (RIS). The natural history and clinical approach to patients with RIS are reviewed in this article.