Medicine and Health Sciences Commons^™

Loss-Of-Function Variants In Endothelial Lipase Are A Cause Of Elevated Hdl Cholesterol In Humans, Andrew Edmondson, Robert Brown, Sekar Kathiresan, L. Cupples, Serkalem Demissie, Alisa Manning, Majken Jensen, Eric Rimm, Jian Wang, Amrith Rodrigues, Vaneeta Bamba, Sumeet Khetarpal, Megan Wolfe, Stephanie Derohannessian, Mingyao Li, Muredach Reilly, Jens Aberle, David Evans, Robert Hegele, Daniel Rader

Dr Robert Brown

Elevated plasma concentrations of HDL cholesterol (HDL-C) are associated with protection from atherosclerotic cardiovascular disease. Animal models indicate that decreased expression of endothelial lipase (LIPG) is inversely associated with HDL-C levels, and genome-wide association studies have identified LIPG variants as being associated with HDL-C levels in humans. We hypothesized that loss-of-function mutations in LIPG may result in elevated HDL-C and therefore performed deep resequencing of LIPG exons in cases with elevated HDL-C levels and controls with decreased HDL-C levels. We identified a significant excess of nonsynonymous LIPG variants unique to cases with elevated HDL-C. In vitro lipase activity assays demonstrated …

Prediction Of Radiation Pneumonitis By Dose-Volume Histogram Parameters In Lung Cancer--A Systematic Review, George Rodrigues, Michael Lock, David D'Souza, Edward Yu, Jake Van Dyk

Michael Lock

BACKGROUND AND PURPOSE: To perform a systematic review of the predictive ability of various dose-volume histogram (DVH) parameters (V(dose), mean lung dose (MLD), and normal tissue complication probability (NTCP)) in the incidence of radiation pneumonitis (RP) caused by external-beam radiation therapy.

METHODS AND MATERIALS: Studies assessing the relationship between CT-based DVH reduction parameters and RP rate in radically treated lung cancer were eligible for the review. Synonyms for RP, lung cancer, DVH and its associated parameters (NTCP, V(20), V(30), MLD) were combined in a search strategy involving electronic databases, secondary reference searching, and consultation with experts. Individual or group data …

Dendritic Cells In Hepatitis C Infection: Can They (Help) Win The Battle, Angela Dolganiuc, Gyongyi Szabo

Gyongyi Szabo

Infection with hepatitis C virus (HCV) is a public health problem; it establishes a chronic course in ~85% of infected patients and increases their risk for developing liver cirrhosis, hepatocellular carcinoma, and significant extrahepatic manifestations. The mechanisms of HCV persistence remain elusive and are largely related to inefficient clearance of the virus by the host immune system. Dendritic cells (DCs) are the most efficient inducers of immune responses; they are capable of triggering productive immunity and maintaining the state of tolerance to self- and non-self antigens. During the past decade, multiple research groups have focused on DCs, in hopes of …

Hypoxia And Hypoxia Inducible Factors: Diverse Roles In Liver Diseases, Bharath Nath, Gyongyi Szabo

Gyongyi Szabo

Hypoxia has been shown to have a role in the pathogenesis of several forms of liver disease. The hypoxia inducible factors (HIFs) are a family of evolutionarily conserved transcriptional regulators that affect a homeostatic response to low oxygen tension and have been identified as key mediators of angiogenesis, inflammation, and metabolism. In this review we summarize the evidence for a role of HIFs across a range of hepatic pathophysiology. We describe regulation of the HIFs and review investigations that demonstrate a role for HIFs in the development of liver fibrosis, activation of innate immune pathways, hepatocellular carcinoma, as well as …

Mitochondrial Antiviral Signaling Protein Defect Links Impaired Antiviral Response And Liver Injury In Steatohepatitis In Mice, Timea Csak, Angela Dolganiuc, Karen Kodys, Bharath Nath, Jan Petrasek, Shashi Bala, Dora Lippai, Gyongyi Szabo

Gyongyi Szabo

Mitochondrial dysfunction is a pathogenic feature of nonalcoholic steatohepatitis (NASH). NASH complicates hepatotropic viral disease. The mitochondrial antiviral signaling protein (MAVS) is the adapter of helicase receptors involved in sensing double-stranded RNA (dsRNA). We hypothesized that impaired MAVS function may contribute to insufficient antiviral response and liver damage in steatohepatitis. We identified reduced MAVS protein levels and increased MAVS association with the proteasome subunit alpha type 7 (PSMA7) in livers from mice given a methionine-choline-deficient (MCD) diet. Decreased association of MAVS with mitochondria and increased cytosolic cytochrome c indicated mitochondrial damage in steatohepatitis. In vivo administration of the synthetic dsRNA …

An Essential Role For Monocyte Chemoattractant Protein-1 In Alcoholic Liver Injury: Regulation Of Proinflammatory Cytokines And Hepatic Steatosis In Mice, Pranoti Mandrekar, Aditya Ambade, Arlene Lim, Gyongyi Szabo, Donna Catalano

Gyongyi Szabo

The importance of chemokines in alcoholic liver injury has been implicated. The role of the chemokine, monocyte chemoattractant protein-1 (MCP-1), elevated in patients with alcoholic liver disease is not yet understood. Here, we evaluated the pathophysiological significance of MCP-1 and its receptor, chemokine (C-C motif) receptor 2 (CCR2), in alcoholic liver injury. The Leiber-DeCarli diet containing alcohol or isocaloric control diets were fed to wild-type (WT) and MCP-1-deficient knockout (KO) mice for 6 weeks. In vivo and in vitro assays were performed to study the role of MCP-1 in alcoholic liver injury. MCP-1 was increased in Kupffer cells (KCs) as …

Novel Developmental Biology-Based Protocol Of Embryonic Stem Cell Differentiation To Morphologically Sound And Functional Yet Immature Hepatocytes, Terence Bukong, Tracie Lo, Gyongyi Szabo, Angela Dolganiuc

Gyongyi Szabo

BACKGROUND/AIMS: Liver diseases are common in the United States and often require liver transplantation; however, donated organs are limited and thus alternative sources for liver cells are in high demand. Embryonic stem cells (ESC) can provide a continuous and readily available source of liver cells. ESC differentiation to liver cells is yet to be fully understood and comprehensive differentiation protocols are yet to be defined. Here, we aimed to achieve human (h)ESC differentiation into mature hepatocytes using defined recombinant differentiation factors and metabolites. METHODS: Embryonic stem cell H1 line was sub-cultured on feeder layer. We induced hESCs into endodermal differentiation …

Tubercular Pancreatic Abscess Presenting As Fever And Cystic Pancreatic Lesion With Endoscopic Management., Jonathan Fenkel, Maya Spodik, Bheema Singu, Anthony Infantolino, Sandeep Deshmukh, David Loren

Sandeep Deshmukh

Isolated pancreatic tuberculosis is a rare presentation of tubercular infection. There are few reported cases of pancreatic tuberculosis diagnosed by endoscopic ultrasound with fine-needle aspiration (EUS FNA), though EUS is often used in the evaluation of pancreatic cystic lesions. We present a case of a tubercular pancreatic abscess presenting as a cystic lesion in a patient with undiagnosed immunodeficiency. The abscess was aspirated by EUS FNA and treated with endoscopic drainage and anti-mycobacterial medications.

A Prospective Study Of The Rate Of Progression In Compensated, Histologically Advanced Chronic Hepatitis C, Jules Dienstag, Marc Ghany, Timothy Morgan, Adrian Di Bisceglie, Herbert Bonkovsky, Hae-Young Kim, Leonard Seeff, Gyongyi Szabo, Elizabeth Wright, Richard Sterling, Gregory Everson, Karen Lindsay, William Lee, Anna Lok, Chihiro Morishima, Anne Stoddard, James Everhart

Gyongyi Szabo

The incidence of liver disease progression among subjects with histologically advanced but compensated chronic hepatitis C is incomplete. The Hepatitis C Antiviral Long-term Treatment against Cirrhosis Trial was a randomized study of 3.5 years of maintenance peginterferon treatment on liver disease progression among patients who had not cleared virus on peginterferon and ribavirin therapy. Patients were followed subsequently off therapy. Because maintenance peginterferon treatment did not alter liver disease progression, we analyzed treated and control patients together. Among 1,050 subjects (60% advanced fibrosis, 40% cirrhosis), we determined the rate of progression to cirrhosis over 4 years and of clinical outcomes …

Long-Stay Patients In State Psychiatric Hospitals At The End Of The 20th Century, William Fisher, Paul Barreira, Jeffrey Geller, Andrew White, Alisa Lincoln, Marylou Sudders

Alisa Lincoln

OBJECTIVES: The purpose of this study was to assess the characteristics of long-stay patients in contemporary state psychiatric hospitals and to identify factors representing possible barriers to alternative placements for these patients. METHODS: All patients in inpatient units of the Massachusetts Department of Mental Health who had been hospitalized for at least three years as of April 1, 1999, were assessed by their treatment teams with a standardized data collection instrument. Domains assessed included medical problems, need for nursing care, psychiatric diagnosis, and history of problematic behaviors. RESULTS: The 330 individuals identified as long-stay patients had an array of medical …

Insurance Status And Length Of Stay For Involuntarily Hospitalized Patients, William Fisher, Paul Barreira, Alisa Lincoln, Lorna Simon, Andrew White, Kristen Roy-Bujnowski, Marylou Sudders

Alisa Lincoln

General and private psychiatric hospitals are becoming increasingly common as sites for involuntary hospitalization. Unlike the public facilities that these settings are supplanting, these hospitals must pay strict attention to issues associated with reimbursement, insurance status, and managed care. This article examines the effects of insurance status on length of stay for involuntarily hospitalized patients in general and private hospitals in Massachusetts. Using a two-stage sampling procedure, data on episodes of involuntary hospitalization were gathered and assessed using multiple regression. The primary effect was found between patients with Medicare, who had the longest stays, and individuals who were uninsured, who …

Parameters For Establishing Humanized Mouse Models To Study Human Immunity: Analysis Of Human Hematopoietic Stem Cell Engraftment In Three Immunodeficient Strains Of Mice Bearing The Il2rgamma(Null) Mutation, Michael Brehm, Amy Cuthbert, Chaoxing Yang, David Miller, Philip Diiorio, Joseph Laning, Lisa Burzenski, Bruce Gott, Oded Foreman, Anoop Kavirayani, Mary Herlihy, Aldo Rossini, Leonard Shultz, Dale Greiner

Philip J diIorio Jr

"Humanized" mouse models created by engraftment of immunodeficient mice with human hematolymphoid cells or tissues are an emerging technology with broad appeal across multiple biomedical disciplines. However, investigators wishing to utilize humanized mice with engrafted functional human immune systems are faced with a myriad of variables to consider. In this study, we analyze HSC engraftment methodologies using three immunodeficient mouse strains harboring the IL2rgamma(null) mutation; NOD-scid IL2rgamma(null), NOD-Rag1(null) IL2rgamma(null), and BALB/c-Rag1(null) IL2rgamma(null) mice. Strategies compared engraftment of human HSC derived from umbilical cord blood following intravenous injection into adult mice and intracardiac and intrahepatic injection into newborn mice. We observed …

Human Immune System Development And Rejection Of Human Islet Allografts In Spontaneously Diabetic Nod-Rag1null Il2rgammanull Ins2akita Mice, Michael Brehm, Rita Bortell, Philip Diiorio, Jean Leif, Joseph Laning, Amy Cuthbert, Chaoxing Yang, Mary Herlihy, Lisa Burzenski, Bruce Gott, Oded Foreman, Alvin Powers, Dale Greiner, Leonard Shultz

Philip J diIorio Jr

OBJECTIVE: To create an immunodeficient mouse model that spontaneously develops hyperglycemia to serve as a diabetic host for human islets and stem cell-derived beta-cells in the absence or presence of a functional human immune system.

RESEARCH DESIGN AND METHODS: We backcrossed the Ins2(Akita) mutation onto the NOD-Rag1(null) IL2rgamma(null) strain and determined 1) the spontaneous development of hyperglycemia, 2) the ability of human islets, mouse islets, and dissociated mouse islet cells to restore euglycemia, 3) the generation of a human immune system following engraftment of human hematopoietic stem cells, and 4) the ability of the humanized mice to reject human islet …

Primary Care, Economic Barriers To Health Care, And Use Of Colorectal Cancer Screening Tests Among Medicare Enrollees Over Time, Chyke Doubeni, Adeyinka Laiyemo, Angela Higgins, Carrie Klabunde, George Reed, Terry Field, Robert Fletcher

Chyke A. Doubeni

PURPOSE: Colorectal cancer (CRC) screening remains underutilized. The objective of this study was to examine the impact of primary care and economic barriers to health care on CRC testing relative to the 2001 Medicare expansion of screening coverage.

METHODS: Medicare Current Beneficiary Survey data were use to study community-dwelling enrollees aged 65 to 80 years, free of renal disease and CRC, and who participated in the survey in 2000 (n = 8,330), 2003 (n = 7,889), or 2005 (n = 7,614). Three outcomes were examined: colonoscopy/sigmoidoscopy within 5 years (recent endoscopy), endoscopy more than 5 years previously, and fecal occult …

Socioeconomic And Racial Patterns Of Colorectal Cancer Screening Among Medicare Enrollees In 2000 To 2005, Chyke Doubeni, Adeyinka Laiyemo, George Reed, Terry Field, Robert Fletcher

Chyke A. Doubeni

BACKGROUND: Lower rates of screening among minorities and low-income populations contribute to colorectal cancer health disparities. Therefore, we examined patterns of colorectal cancer screening and associations with race-ethnicity, education, and income over time. METHODS: Repeated cross-sectional data from the Medicare Current Beneficiary Survey of noninstitutionalized colorectal cancer-free Medicare enrollees ages 65 to 80 years interviewed in 2000 (n = 8,355), 2003 (n = 7,922), and 2005 (n = 7,646). We examined rates of colonoscopy/sigmoidoscopy use within 5 years (recent endoscopy), colonoscopy/sigmoidoscopy use >5 years previously, or fecal occult blood test (FOBT) within 2 years. RESULTS: Among those included in the …

Race And Colorectal Cancer Disparities: Health-Care Utilization Vs Different Cancer Susceptibilities, Adeyinka Laiyemo, Chyke Doubeni, Paul Pinsky, V. Doria-Rose, Robert Bresalier, Lois Lamerato, E. Crawford, Paul Kvale, Mona Fouad, Thomas Hickey, Thomas Riley, Joel Weissfeld, Robert Schoen, Pamela Marcus, Philip Prorok, Christine Berg

Chyke A. Doubeni

BACKGROUND: It is unclear whether the disproportionately higher incidence and mortality from colorectal cancer among blacks compared with whites reflect differences in health-care utilization or colorectal cancer susceptibility. METHODS: A total of 60, 572 non-Hispanic white and black participants in the ongoing Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial underwent trial-sponsored screening flexible sigmoidoscopy (FSG) without biopsy at baseline in 10 geographically dispersed centers from November 1993 to July 2001. Subjects with polyps or mass lesions detected by FSG were referred to their physicians for diagnostic workup, the cost of which was not covered by PLCO. The records …

Early Course Of Nicotine Dependence In Adolescent Smokers, Chyke Doubeni, George Reed, Joseph Difranza

Chyke A. Doubeni

OBJECTIVE: The goal was to characterize the early course of nicotine dependence. METHODS: Data were collected from 1246 sixth-graders in a 4-year (2002-2006) prospective study using 11 individual interviews. Subjects were monitored for 10 symptoms of dependence by using the Hooked on Nicotine Checklist. The bidirectional prospective relationship between the intensity of dependence (number of symptoms) and smoking frequency was examined by using cross-lagged analyses. RESULTS: Of the 370 subjects who had inhaled from a cigarette, 62% smoked at least once per month, 53% experienced dependence symptoms, and 40% experienced escalation to daily smoking. Smoking frequency predicted the number of …

Likelihood Of Missed And Recurrent Adenomas In The Proximal Versus The Distal Colon, Adeyinka Laiyemo, Chyke Doubeni, Andrew Sanderson, Paul Pinsky, Dilhana Badurdeen, V. Doria-Rose, Pamela Marcus, Robert Schoen, Elaine Lanza, Arthur Schatzkin, Amanda Cross

Chyke A. Doubeni

BACKGROUND: Colonoscopy may be less efficacious in reducing colorectal cancer mortality in the proximal compared with the distal colon. A greater likelihood for missed and recurrent adenomas in the proximal colon may contribute to this phenomenon.

OBJECTIVE: To examine whether a proximal adenoma is associated with the risk and location of missed and recurrent adenomas.

DESIGN: Prospective.

SETTING: Polyp Prevention Trial.

PARTICIPANTS: A total of 1864 patients with an adenoma at baseline underwent a follow-up colonoscopy 4 years later (adenoma recurrence). Of these, 1731 underwent a clearing colonoscopy 1 year after the baseline examination (missed adenoma).

MAIN OUTCOME MEASUREMENTS: Association …

Racial And Ethnic Trends Of Colorectal Cancer Screening Among Medicare Enrollees, Chyke Doubeni, Adeyinka Laiyemo, Carrie Klabunde, Angela Higgins, Terry Field, Robert Fletcher

Chyke A. Doubeni

BACKGROUND: Colorectal cancer (CRC) screening rates have remained lower than the Healthy People 2010 goal, particularly among minority populations. PURPOSE: This study aimed to examine the racial-ethnic trends in CRC screening and the continued impact of healthcare access indicators on screening differences after Medicare expanded coverage. METHODS: The study used data from the Medicare Current Beneficiary Survey for 2000, 2003, and 2005. The sample was restricted to non-Hispanic whites, non-Hispanic blacks, and Hispanics. The primary outcome was the proportion of enrollees who underwent lower-gastrointestinal endoscopy within 5 years and/or home fecal occult blood test within 1 year. RESULTS: Over the …

A 25-Year Perspective Into The Changing Landscape Of Patients Hospitalized With Acute Myocardial Infarction (The Worcester Heart Attack Study), Robert Goldberg, Frederick Spencer, Jorge Yarzebski, Darleen Lessard, Joel Gore, Joseph Alpert, James Dalen

Jorge L. Yarzebski

Over the past several decades, significant advances have been made in the primary and secondary prevention of coronary artery disease. However, effects of changing lifestyle and treatment practices on demographic and clinical profiles and on hospital outcomes of patients who present with acute myocardial infarction (AMI) have not been well characterized. We carried out a prospective population-based investigation of >25-year trends (1975 to 2001) in demographic and clinical characteristics, treatment practices, and hospital outcomes of patients who had been hospitalized with AMI. Residents of a metropolitan area (Worcester, Massachusetts) who had been hospitalized with validated AMI (n = 10,440) in …