Showing papers by "Vanderbilt University published in 2005"
27 Oct 2005
TL;DR: A public database of common variation in the human genome: more than one million single nucleotide polymorphisms for which accurate and complete genotypes have been obtained in 269 DNA samples from four populations, including ten 500-kilobase regions in which essentially all information about common DNA variation has been extracted.
Abstract: Inherited genetic variation has a critical but as yet largely uncharacterized role in human disease. Here we report a public database of common variation in the human genome: more than one million single nucleotide polymorphisms (SNPs) for which accurate and complete genotypes have been obtained in 269 DNA samples from four populations, including ten 500-kilobase regions in which essentially all information about common DNA variation has been extracted. These data document the generality of recombination hotspots, a block-like structure of linkage disequilibrium and low haplotype diversity, leading to substantial correlations of SNPs with many of their neighbours. We show how the HapMap resource can guide the design and analysis of genetic association studies, shed light on structural variation and recombination, and identify loci that may have been subject to natural selection during human evolution.
5,479 citations
TL;DR: In this article, the defining features of single-subject research are presented, the con- tributions of single subject research for special education are reviewed, and a specific proposal is of- fered for using singlesubject research to document evidence-based practice.
Abstract: Slnglesubject research plays an important role in the development of evidence-based practice in special education. The defining features of single-subject research are presented, the con- tributions oj single-subject research for special education are reviewed, and a specific proposal is of- fered for using single-subject research to document evidence-based practice. This article allows readers to determine if a specific study is a credible example of single-subject research and if a spe- cific practice or procedure has been validated as "evidence-based" via single-subject research.
3,038 citations
TL;DR: In this paper, the results of the PHENIX detector at the Relativistic Heavy Ion Collider (RHIC) were examined with an emphasis on implications for the formation of a new state of dense matter.
2,572 citations
Veterans Health Administration1, University of California, San Diego2, University of Colorado Denver3, Duke University4, National Institutes of Health5, Washington University in St. Louis6, New York University7, Columbia University8, University of Rochester9, Vanderbilt University10, Baylor College of Medicine11, University of Texas at San Antonio12, United States Department of Veterans Affairs13, Merck & Co.14, University of California, Los Angeles15
TL;DR: The zoster vaccine markedly reduced morbidity from herpes zoster and postherpetic neuralgia among older adults and significantly reduced the burden of illness due to herpesZoster.
Abstract: background The incidence and severity of herpes zoster and postherpetic neuralgia increase with age in association with a progressive decline in cell-mediated immunity to varicella– zoster virus (VZV). We tested the hypothesis that vaccination against VZV would decrease the incidence, severity, or both of herpes zoster and postherpetic neuralgia among older adults. methods We enrolled 38,546 adults 60 years of age or older in a randomized, double-blind, placebo-controlled trial of an investigational live attenuated Oka/Merck VZV vaccine (“zoster vaccine”). Herpes zoster was diagnosed according to clinical and laboratory criteria. The pain and discomfort associated with herpes zoster were measured repeatedly for six months. The primary end point was the burden of illness due to herpes zoster, a measure affected by the incidence, severity, and duration of the associated pain and discomfort. The secondary end point was the incidence of postherpetic neuralgia. results More than 95 percent of the subjects continued in the study to its completion, with a median of 3.12 years of surveillance for herpes zoster. A total of 957 confirmed cases of herpes zoster (315 among vaccine recipients and 642 among placebo recipients) and 107 cases of postherpetic neuralgia (27 among vaccine recipients and 80 among placebo recipients) were included in the efficacy analysis. The use of the zoster vaccine reduced the burden of illness due to herpes zoster by 61.1 percent (P<0.001), reduced the incidence of postherpetic neuralgia by 66.5 percent (P<0.001), and reduced the incidence of herpes zoster by 51.3 percent (P<0.001). Reactions at the injection site were more frequent among vaccine recipients but were generally mild. conclusions The zoster vaccine markedly reduced morbidity from herpes zoster and postherpetic neuralgia among older adults.
2,060 citations
TL;DR: It is shown that mice expressing a proofreading-deficient version of the mitochondrial DNA polymerase g (POLG) accumulate mt DNA mutations and display features of accelerated aging, suggesting that accumulation of mtDNA mutations that promote apoptosis may be a central mechanism driving mammalian aging.
Abstract: Mutations in mitochondrial DNA (mtDNA) accumulate in tissues of mammalian species and have been hypothesized to contribute to aging. We show that mice expressing a proofreading-deficient version of the mitochondrial DNA polymerase g (POLG) accumulate mtDNA mutations and display features of accelerated aging. Accumulation of mtDNA mutations was not associated with increased markers of oxidative stress or a defect in cellular proliferation, but was correlated with the induction of apoptotic markers, particularly in tissues characterized by rapid cellular turnover. The levels of apoptotic markers were also found to increase during aging in normal mice. Thus, accumulation of mtDNA mutations that promote apoptosis may be a central mechanism driving mammalian aging.
1,920 citations
TL;DR: It is found that ensemble fMRI signals in early visual areas could reliably predict on individual trials which of eight stimulus orientations the subject was seeing, when subjects had to attend to one of two overlapping orthogonal gratings.
Abstract: The potential for human neuroimaging to read out the detailed contents of a person's mental state has yet to be fully explored. We investigated whether the perception of edge orientation, a fundamental visual feature, can be decoded from human brain activity measured with functional magnetic resonance imaging (fMRI). Using statistical algorithms to classify brain states, we found that ensemble fMRI signals in early visual areas could reliably predict on individual trials which of eight stimulus orientations the subject was seeing. Moreover, when subjects had to attend to one of two overlapping orthogonal gratings, feature-based attention strongly biased ensemble activity toward the attended orientation. These results demonstrate that fMRI activity patterns in early visual areas, including primary visual cortex (V1), contain detailed orientation information that can reliably predict subjective perception. Our approach provides a framework for the readout of fine-tuned representations in the human brain and their subjective contents.
1,843 citations
TL;DR: An overview of the many types of studies that fall into the qualitative design genre is provided in this paper, along with strategies that qualitative researchers use to establish the authors' studies as credible and trustworthy.
Abstract: An overview of the many types of studies that fall into the qualitative design genre is provided. Strategies that qualitative researchers use to establish the authors' studies as credible and trustworthy are listed and defined. So that readers will recognize the important contribution qualitative studies have made in the field of special education, a range of well-known and lesser known examples of qualitative research are reviewed. The quality indicators that are important in conducting and evaluating qualitative research are identified. Finally, as an example of the evidence that can be produced using qualitative methods, the authors provide a summary of how 3 studies have provided important information that can be used to inform policy and practice.
1,591 citations
TL;DR: It is shown that overexpression of Klotho in mice extends life span and it is suggested that Klotha-mediated inhibition of insulin and IGF1 signaling contributes to its anti-aging properties.
Abstract: A defect in Klotho gene expression in mice accelerates the degeneration of multiple age-sensitive traits. Here, we show that overexpression of Klotho in mice extends life span. Klotho protein functions as a circulating hormone that binds to a cell-surface receptor and represses intracellular signals of insulin and insulin-like growth factor 1 (IGF1), an evolutionarily conserved mechanism for extending life span. Alleviation of aging-like phenotypes in Klotho-deficient mice was observed by perturbing insulin and IGF1 signaling, suggesting that Klotho-mediated inhibition of insulin and IGF1 signaling contributes to its anti-aging properties. Klotho protein may function as an anti-aging hormone in mammals.
1,583 citations
TL;DR: In this article, the authors propose that consumers purchase brands in part to construct their self-concepts and, in so doing, form self-brand connections, and they focus on reference groups as a source of brand meaning.
Abstract: We propose that consumers purchase brands in part to construct their self-concepts and, in so doing, form self-brand connections. We focus on reference groups as a source of brand meaning. Results from two studies show that brands with images consistent with an ingroup enhance self-brand connections for all consumers, whereas brands with images that are consistent with an outgroup have a stronger negative effect on independent versus interdependent consumers. We propose that this differential effect is due to stronger self-differentiation goals for consumers with more independent self-concepts. We also find greater effects for more symbolic than for less symbolic brands.
1,580 citations
TL;DR: These functional CB2 receptors in the brainstem were activated by a CB2 receptor agonist, 2-arachidonoylglycerol, and by elevated endogenous levels of endocannabinoids, which also act at CB1 receptors.
Abstract: The presence and function of CB2 receptors in central nervous system (CNS) neurons are controversial. We report the expression of CB2 receptor messenger RNA and protein localization on brainstem neurons. These functional CB2 receptors in the brainstem were activated by a CB2 receptor agonist, 2-arachidonoylglycerol, and by elevated endogenous levels of endocannabinoids, which also act at CB1 receptors. CB2 receptors represent an alternative site of action of endocannabinoids that opens the possibility of nonpsychotropic therapeutic interventions using enhanced endocannabinoid levels in localized brain areas.
1,466 citations
Journal Article•
TL;DR: The extensive testing of the OLINDA/EXM code, based on comparison with literature-established dose calculations and with the widely tested and accepted MIRDOSE3.1 code, should give users confidence in its output, and should be easy for MIRDose users to adopt and for new users to understand.
Abstract: The OLINDA/EXM version 1.0 personal computer code was created as a replacement for the widely used MIRDOSE3.1 code. This paper documents the basic function of the code and how it is similar to and different from the MIRDOSE software. Methods: After creation of the code and α- and β-testing phases, a premarket notification submission (510(k)) was filed with the Food and Drug Administration to permit marketing of the code. Permission was granted in June 2004, and the code is currently being distributed through Vanderbilt University. Not all of the technical details of the dosimetry methods have been shown here, as they have been previously documented. Results: Agreement of doses between the MIRDOSE3.1 and OLINDA/EXM codes was good, within 1%–2% in most cases. Conclusion: The extensive testing of the OLINDA/EXM code, based on comparison with literature-established dose calculations and with the widely tested and accepted MIRDOSE3.1 code, should give users confidence in its output. The OLINDA/EXM code should be easy for MIRDOSE users to adopt and for new users to understand. It will be useful in standardizing and automating internal dose calculations, assessing doses in clinical trials with radiopharmaceuticals, making theoretic calculations for existing pharmaceuticals, teaching, and other purposes.
University of Florida1, Duke University2, Harvard University3, University of Cincinnati4, University of Michigan5, Johns Hopkins University6, University of North Carolina at Chapel Hill7, University of California, Los Angeles8, University of Texas Southwestern Medical Center9, University of Minnesota10, Mayo Clinic11, Ohio State University12, Northwestern University13, University of Calgary14, University of Kentucky15, Cleveland Clinic16, Vanderbilt University17, University of Alabama18, Case Western Reserve University19, University of Washington20, University of California, San Francisco21, University of Wisconsin-Madison22
TL;DR: Therapy to reduce volume overload during hospitalization for heart failure led to marked improvement in signs and symptoms of elevated filling pressures with or without the PAC, which reached significance for the time trade-off at all time points after randomization.
Abstract: Context Pulmonary artery catheters (PACs) have been used to guide therapy in multiple settings, but recent studies have raised concerns that PACs may lead to increased mortality in hospitalized patients. Objective To determine whether PAC use is safe and improves clinical outcomes in patients hospitalized with severe symptomatic and recurrent heart failure. Design, setting, and participants The Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness (ESCAPE) was a randomized controlled trial of 433 patients at 26 sites conducted from January 18, 2000, to November 17, 2003. Patients were assigned to receive therapy guided by clinical assessment and a PAC or clinical assessment alone. The target in both groups was resolution of clinical congestion, with additional PAC targets of a pulmonary capillary wedge pressure of 15 mm Hg and a right atrial pressure of 8 mm Hg. Medications were not specified, but inotrope use was explicitly discouraged. Main outcome measures The primary end point was days alive out of the hospital during the first 6 months, with secondary end points of exercise, quality of life, biochemical, and echocardiographic changes. Results Severity of illness was reflected by the following values: average left ventricular ejection fraction, 19%; systolic blood pressure, 106 mm Hg; sodium level, 137 mEq/L; urea nitrogen, 35 mg/dL (12.40 mmol/L); and creatinine, 1.5 mg/dL (132.6 micromol/L). Therapy in both groups led to substantial reduction in symptoms, jugular venous pressure, and edema. Use of the PAC did not significantly affect the primary end point of days alive and out of the hospital during the first 6 months (133 days vs 135 days; hazard ratio [HR], 1.00 [95% confidence interval {CI}, 0.82-1.21]; P = .99), mortality (43 patients [10%] vs 38 patients [9%]; odds ratio [OR], 1.26 [95% CI, 0.78-2.03]; P = .35), or the number of days hospitalized (8.7 vs 8.3; HR, 1.04 [95% CI, 0.86-1.27]; P = .67). In-hospital adverse events were more common among patients in the PAC group (47 [21.9%] vs 25 [11.5%]; P = .04). There were no deaths related to PAC use, and no difference for in-hospital plus 30-day mortality (10 [4.7%] vs 11 [5.0%]; OR, 0.97 [95% CI, 0.38-2.22]; P = .97). Exercise and quality of life end points improved in both groups with a trend toward greater improvement with the PAC, which reached significance for the time trade-off at all time points after randomization. Conclusions Therapy to reduce volume overload during hospitalization for heart failure led to marked improvement in signs and symptoms of elevated filling pressures with or without the PAC. Addition of the PAC to careful clinical assessment increased anticipated adverse events, but did not affect overall mortality and hospitalization. Future trials should test noninvasive assessments with specific treatment strategies that could be used to better tailor therapy for both survival time and survival quality as valued by patients.
TL;DR: The metabolic syndrome is highly prevalent in US schizophrenia patients and represents an enormous source of cardiovascular risk, especially for women, so clinical attention must be given to monitoring for this syndrome, and minimizing metabolic risks associated with antipsychotic treatment.
TL;DR: Current issues on the two apparent primary mechanisms--the redistribution of catecholamines from synaptic vesicles to the cytosol, and induction of reverse transport of transmitter through plasma membrane uptake carriers are reviewed.
TL;DR: A decade ago, Walker et al. as mentioned in this paper proposed a model of the parental involvement process that focused on understanding why parents become involved in their children's education and how their involvement influences student outcomes.
Abstract: A decade ago, Hoover‐Dempsey and Sandler offered a model of the parental involvement process that focused on understanding why parents become involved in their children’s education and how their involvement influences student outcomes. Since then, we and others have conducted conceptual and empirical work to enhance understanding of processes examined in the model. In this article (companion to Walker and colleagues’ article about scale development on the model in this issue), we review recent work on constructs central to the model’s initial question: Why do parents become involved in children’s education? Based on this review, we offer suggestions for (1) research that may deepen understanding of parents’ motivations for involvement and (2) school and family practices that may strengthen the incidence and effectiveness of parental involvement across varied school communities.
TL;DR: The development of portable accelerometers has made objective assessments of physical activity possible and nonlinear approaches to predict energy expenditure using accelerometer outputs from multiple sites and orientation can enhance accuracy.
Abstract: Purpose:This paper reviews accelerometry-based activity monitors, including single-site first-generation devices, emerging technologies, and analytical approaches to predict energy expenditure, with suggestions for further research and development.Methods:The physics and measurement principl
TL;DR: This article focuses on the cytochrome P-450 enzymes, a superfamily of microsomal drug-metabolizing enzymes that play an important role in oxidative drug metabolism.
Abstract: Differences in drug responsiveness are common, often leading to challenges in optimizing the dosage regimen for a particular patient. Recent advances provide a rational framework for understanding many interpatient differences in drug disposition and their clinical consequences. This article focuses on the cytochrome P-450 enzymes, a superfamily of microsomal drug-metabolizing enzymes that play an important role in oxidative drug metabolism.
TL;DR: In this article, the authors present quality indicators for experimental and quasi-experimental studies for special education, intended not only to evaluate the merits of a completed research report or article but also to serve as an organizer of critical issues for consideration in research.
Abstract: This article presents quality indicators for experimental and quasi-experimental studies for special education. These indicators are intended not only to evaluate the merits of a completed research report or article but also to serve as an organizer of critical issues for consideration in research. We believe these indicators can be used widely, from assisting in the development of research plans to evaluating proposals. In this article, the framework and rationale is explained by providing brief descriptions of each indicator. Finally, we suggest a standard for determining whether a practice may be considered evidence-based. It is our intent that this standard for evidenced-based practice and the indicators be reviewed, revised as needed, and adopted by the field of special education.
TL;DR: Cognitive therapy can be as effective as medications for the initial treatment of moderate to severe major depression, but this degree of effectiveness may depend on a high level of therapist experience or expertise.
Abstract: Background There is substantial evidence that antidepressant medications treat moderate to severe depression effectively, but there is less data on cognitive therapy’s effects in this population. Objective To compare the efficacy in moderate to severe depression of antidepressant medications with cognitive therapy in a placebo-controlled trial. Design Random assignment to one of the following: 16 weeks of medications (n = 120), 16 weeks of cognitive therapy (n = 60), or 8 weeks of pill placebo (n = 60). Setting Research clinics at the University of Pennsylvania, Philadelphia, and Vanderbilt University, Nashville, Tenn. Patients Two hundred forty outpatients, aged 18 to 70 years, with moderate to severe major depressive disorder. Interventions Some study subjects received paroxetine, up to 50 mg daily, augmented by lithium carbonate or desipramine hydrochloride if necessary; others received individual cognitive therapy. Main Outcome Measure The Hamilton Depression Rating Scale provided continuous severity scores and allowed for designations of response and remission. Results At 8 weeks, response rates in medications (50%) and cognitive therapy (43%) groups were both superior to the placebo (25%) group. Analyses based on continuous scores at 8 weeks indicated an advantage for each of the active treatments over placebo, each with a medium effect size. The advantage was significant for medication relative to placebo, and at the level of a nonsignificant trend for cognitive therapy relative to placebo. At 16 weeks, response rates were 58% in each of the active conditions; remission rates were 46% for medication, 40% for cognitive therapy. Follow-up tests of a site × treatment interaction indicated a significant difference only at Vanderbilt University, where medications were superior to cognitive therapy. Site differences in patient characteristics and in the relative experience levels of the cognitive therapists each appear to have contributed to this interaction. Conclusion Cognitive therapy can be as effective as medications for the initial treatment of moderate to severe major depression, but this degree of effectiveness may depend on a high level of therapist experience or expertise.
TL;DR: In this paper, the authors set the context for the development of research quality indicators and guidelines for evidence of effective practices provided by different methodologies in the context of special education research.
Abstract: This article sets the context for the development of research quality indicators and guidelines for evidence of effective practices provided by different methodologies. The current conceptualization of scientific research in education and the complexity of conducting research in special education settings underlie the development of quality indicators. Programs of research in special education may be viewed as occurring in stages: moving from initial descriptive research, to experimental causal research, to finally research that examines the processes that might affect wide-scale adoption and use of a practice. At each stage, different research questions are relevant, and different research methodologies to address the research questions are needed.
TL;DR: Evidence that NKCC1 facilitates seizures in the developing brain is provided and indications that bumetanide should be useful in the treatment of neonatal seizures are indicated.
Abstract: During development, activation of Cl(-)-permeable GABA(A) receptors (GABA(A)-R) excites neurons as a result of elevated intracellular Cl(-) levels and a depolarized Cl(-) equilibrium potential (E(Cl)). GABA becomes inhibitory as net outward neuronal transport of Cl(-) develops in a caudal-rostral progression. In line with this caudal-rostral developmental pattern, GABAergic anticonvulsant compounds inhibit motor manifestations of neonatal seizures but not cortical seizure activity. The Na(+)-K(+)-2Cl(-) cotransporter (NKCC1) facilitates the accumulation of Cl(-) in neurons. The NKCC1 blocker bumetanide shifted E(Cl) negative in immature neurons, suppressed epileptiform activity in hippocampal slices in vitro and attenuated electrographic seizures in neonatal rats in vivo. Bumetanide had no effect in the presence of the GABA(A)-R antagonist bicuculline, nor in brain slices from NKCC1-knockout mice. NKCC1 expression level versus expression of the Cl(-)-extruding transporter (KCC2) in human and rat cortex showed that Cl(-) transport in perinatal human cortex is as immature as in the rat. Our results provide evidence that NKCC1 facilitates seizures in the developing brain and indicate that bumetanide should be useful in the treatment of neonatal seizures.
TL;DR: In this article, the authors model the interaction of insiders and outsiders on a corporate board and address the question of the board's ideal size and composition, where insiders are better informed regarding the quality of firm investment projects, but outsiders can use CEO succession to motivate insiders to reveal their superior information and help the board implement higher value projects.
Abstract: This paper models the interaction of firm insiders and outsiders on a corporate board and addresses the question of the board's ideal size and composition. In the model, the board is responsible for monitoring projects and making CEO succession decisions. Inside directors are better informed regarding the quality of firm investment projects, but outsiders can use CEO succession to motivate insiders to reveal their superior information and help the board implement higher value projects. The optimal board structure is determined by the trade-off between maximizing the incentive for insiders to reveal their private information, minimizing coordination costs among outsiders and maximizing the ability of outsiders to reject inferior projects. I show that optimal board size and composition are functions of the directors' and the firm's characteristics. I also develop testable implications for cross sectional variations in the optimal board structure across firms.
TL;DR: Rofecoxib use increases the risk of serious coronary heart disease compared with celecoxib use, and naproxen use does not protect against serious coronaryHeart disease.
TL;DR: A software system GEMS (Gene Expression Model Selector) that automates high-quality model construction and enforces sound optimization and performance estimation procedures is developed, the first such system to be informed by a rigorous comparative analysis of the available algorithms and datasets.
Abstract: Motivation: Cancer diagnosis is one of the most important emerging clinical applications of gene expression microarray technology. We are seeking to develop a computer system for powerful and reliable cancer diagnostic model creation based on microarray data. To keep a realistic perspective on clinical applications we focus on multicategory diagnosis. To equip the system with the optimum combination of classifier, gene selection and cross-validation methods, we performed a systematic and comprehensive evaluation of several major algorithms for multicategory classification, several gene selection methods, multiple ensemble classifier methods and two cross-validation designs using 11 datasets spanning 74 diagnostic categories and 41 cancer types and 12 normal tissue types.
Results: Multicategory support vector machines (MC-SVMs) are the most effective classifiers in performing accurate cancer diagnosis from gene expression data. The MC-SVM techniques by Crammer and Singer, Weston and Watkins and one-versus-rest were found to be the best methods in this domain. MC-SVMs outperform other popular machine learning algorithms, such as k-nearest neighbors, backpropagation and probabilistic neural networks, often to a remarkable degree. Gene selection techniques can significantly improve the classification performance of both MC-SVMs and other non-SVM learning algorithms. Ensemble classifiers do not generally improve performance of the best non-ensemble models. These results guided the construction of a software system GEMS (Gene Expression Model Selector) that automates high-quality model construction and enforces sound optimization and performance estimation procedures. This is the first such system to be informed by a rigorous comparative analysis of the available algorithms and datasets.
Availability: The software system GEMS is available for download from http://www.gems-system.org for non-commercial use.
Contact: alexander.statnikov@vanderbilt.edu
TL;DR: A review of the neurobiological literature suggests that the capacity limit of VSTM storage is primarily localized to the posterior parietal and occipital cortex, whereas the AB and PRP are associated with partly overlapping fronto-parietal networks.
University of Cologne1, University of Freiburg2, Fred Hutchinson Cancer Research Center3, University of Regensburg4, University of Liverpool5, Lund University6, University of Basel7, Discovery Institute8, Imperial College London9, Northwestern University10, National Institutes of Health11, Stanford University12, University of Manchester13, French Institute of Health and Medical Research14, Washington University in St. Louis15, Yokohama City University16, Karolinska Institutet17, Vanderbilt University18, Harvard University19, Max Planck Society20, Osaka University21, University of Copenhagen22, Thomas Jefferson University23, University of Helsinki24, University of Erlangen-Nuremberg25, Rutgers University26
TL;DR: A new identification system for a trimer using three Arabic numerals, based on the alpha, beta and gamma chain numbers is introduced, which is introduced for laminin trimers.
TL;DR: Several strengths of SEM are reviewed, with a particular focus on recent innovations that underscore how SEM has become a broad data-analytic framework with flexible and unique capabilities.
Abstract: Because structural equation modeling (SEM) has become a very popular data-analytic technique, it is important for clinical scientists to have a balanced perception of its strengths and limitations. We review several strengths of SEM, with a particular focus on recent innovations (e.g., latent growth modeling, multilevel SEM models, and approaches for dealing with missing data and with violations of normality assumptions) that underscore how SEM has become a broad data-analytic framework with flexible and unique capabilities. We also consider several limitations of SEM and some misconceptions that it tends to elicit. Major themes emphasized are the problem of omitted variables, the importance of lower-order model components, potential limitations of models judged to be well fitting, the inaccuracy of some commonly used rules of thumb, and the importance of study design. Throughout, we offer recommendations for the conduct of SEM analyses and the reporting of results.
TL;DR: The results suggest that WM deficit in schizophrenia is modality independent and that encoding and/or early part of maintenance may be problematic.
Abstract: Working memory (WM) deficit is a cardinal cognitive symptom of schizophrenia, but the differences among the tasks and measures used to assess WM make it difficult to compare across studies. The authors conducted a meta-analytic review to address 3 major questions: (a) Do patients with schizophrenia show WM deficits across diverse methodology; (b) Is WM deficit supramodal; and (c) Does the WM deficit worsen with longer delays? The results indicate that significant WM deficit was present in schizophrenia patients in all modalities examined. Increasing delay beyond 1 s did not influence the performance difference between schizophrenia patients and healthy control participants in WM. These results suggest that WM deficit in schizophrenia is modality independent and that encoding and/or early part of maintenance may be problematic.
TL;DR: Analysis of islet architecture and composition using confocal laser scanning microscopy indicates that human islets not only are quite heterogeneous in terms of cell composition but also have a substantially different architecture from widely studied murine islets.
Abstract: The recent success of pancreatic islet transplantation has generated considerable enthusiasm. To better understand the quality and characteristics of human islets used for transplantation, we performed detailed analysis of islet architecture and composition using confocal laser scanning microscopy. Human islets from six separate isolations provided by three different islet isolation centers were compared with isolated mouse and non-human primate islets. As expected from histological sections of murine pancreas, in isolated murine islets alpha and delta cells resided at the periphery of the beta-cell core. However, human islets were markedly different in that alpha, beta, and delta cells were dispersed throughout the islet. This pattern of cell distribution was present in all human islet preparations and islets of various sizes and was also seen in histological sections of human pancreas. The architecture of isolated non-human primate islets was very similar to that of human islets. Using an image analysis program, we calculated the volume of alpha, beta, and delta cells. In contrast to murine islets, we found that populations of islet cell types varied considerably in human islets. The results indicate that human islets not only are quite heterogeneous in terms of cell composition but also have a substantially different architecture from widely studied murine islets.
TL;DR: A meta-analysis of 58 experimental and quasi-experimental studies of the effects of cognitive-behavioral therapy on the recidivism of adult and juvenile offenders confirmed prior positive findings and explored a range of potential moderators to identify factors associated with variation in treatment effects as discussed by the authors.
Abstract: A meta-analysis of 58 experimental and quasi-experimental studies of the effects of cognitive-behavioral therapy (CBT) on the recidivism of adult and juvenile offenders confirmed prior positive findings and explored a range of potential moderators to identify factors associated with variation in treatment effects. With method variables controlled, the factors independently associated with larger recidivism reductions were treatment of higher risk offenders, high quality treatment implementation, and a CBT program that included anger control and interpersonal problem solving but not victim impact or behavior modification components. With these factors accounted for, there was no difference in the effectiveness of different brand name CBT programs or generic forms of CBT.