1
|
Wells JM, Yi H, Yang J, Mooney SJ, Quistberg A, Leonard JC. Pediatric emergency department visits for pedestrian injuries in relation to the enactment of Complete Streets policy. Front Public Health 2023; 11:1183997. [PMID: 37670840 PMCID: PMC10475551 DOI: 10.3389/fpubh.2023.1183997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 07/25/2023] [Indexed: 09/07/2023] Open
Abstract
Introduction This study aimed to evaluate the rate of pediatric emergency department (ED) visits for pedestrian injuries in relation to the enactment of the Complete Streets policy. Methods The National Complete Streets policies were codified by county and associated with each hospital's catchment area and date of enactment. Pedestrian injury-related ED visits were identified across 40 children's hospitals within the Pediatric Health Information System (PHIS) from 2004 to 2014. We calculated the proportion of the PHIS hospitals' catchment areas covered by any county policy. We used a generalized linear model to assess the impact of the proportion of the policy coverage on the rate of pedestrian injury-related ED visits. Results The proportion of the population covered by Complete Streets policies increased by 23.9%, and pedestrian injury rates at PHIS hospitals decreased by 29.8% during the study period. After controlling for years, pediatric ED visits for pedestrian injuries did not change with increases in the PHIS catchment population with enacted Complete Streets policies. Conclusion After accounting for time trends, Complete Streets policy enactment was not related to observed changes in ED visits for pedestrian injuries at PHIS hospitals.
Collapse
Affiliation(s)
- Jordee M. Wells
- Division of Emergency Medicine, Department of Pediatrics, Nationwide Children's Hospital, Columbus, OH, United States
| | - Honggang Yi
- Department of Biostatistics, Nanjing Medical University, Nanjing, Jiangsu, China
- Center for Injury Research and Policy, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, United States
| | - Jingzhen Yang
- Center for Injury Research and Policy, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, United States
- Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH, United States
| | - Stephen J. Mooney
- Harborview Injury Prevention and Research Center, University of Washington, Seattle, WA, United States
| | - Alex Quistberg
- Environmental and Occupational Health, Dornslife School of Public Health, Drexel University, Philadelphia, PA, United States
| | - Julie C. Leonard
- Division of Emergency Medicine, Department of Pediatrics, Nationwide Children's Hospital, Columbus, OH, United States
- Center for Injury Research and Policy, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, United States
- Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH, United States
| |
Collapse
|
2
|
Wells JM, Walker VP. "Do No Harm": Promoting Anti-Racist Policing in Pediatric Emergency Departments Through 20 Practice Change Considerations. Health Promot Pract 2023; 24:406-410. [PMID: 36648067 DOI: 10.1177/15248399221145160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Children represent some of the most vulnerable and most valuable members of society. When acutely ill or injured, pediatric emergency departments (EDs) provide first line, specialized care for children and adolescents. Unique and unpredictable, the pediatric ED environment requires a wide range of health care professionals to care for children and their families and often includes hospital-employed security professionals and local law enforcement personnel to ensure safe and protective spaces paramount for optimal patient care. However, an active policing presence within environments designed to promote healing can paradoxically contribute to harm, particularly for Black and Brown patients. As health care systems pledge to dismantle structural racism and achieve health equity, efforts must include anti-racist reforms of threat management systems within clinical environments. We propose assessment and evaluation of current security and police encounters within pediatric EDs. We call for institution of policies that mitigate biases, address medical mistrust, distinguish clinical from criminal aggression, and minimize punitive contact with police. We outline a multitiered, patient-centered approach to disruptive and violent acts that prioritizes prevention, early intervention, and de-escalation strategies with a goal of reducing the perceived need for policing presence in pediatric EDs.
Collapse
Affiliation(s)
- Jordee M Wells
- Nationwide Children's Hospital and The Ohio State University College of Medicine, Columbus, OH, USA
- Nationwide Children's Hospital, Columbus, OH, USA
| | - Valencia P Walker
- Nationwide Children's Hospital and The Ohio State University College of Medicine, Columbus, OH, USA
- University of California, Los Angeles, Los Angeles, CA, USA
| |
Collapse
|
3
|
Pomerantz A, De Souza HG, Hall M, Neuman MI, Goyal MK, Samuels-Kalow ME, Aronson PL, Alpern ER, Simon HK, Hoffmann JA, Wells JM, Shanahan KH, Gutman CK, Peltz A. Racial and Ethnic Differences in Insurer Classification of Nonemergent Pediatric Emergency Department Visits. JAMA Netw Open 2023; 6:e2311752. [PMID: 37140920 PMCID: PMC10160869 DOI: 10.1001/jamanetworkopen.2023.11752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 03/22/2023] [Indexed: 05/05/2023] Open
Abstract
Importance Government and commercial health insurers have recently enacted policies to discourage nonemergent emergency department (ED) visits by reducing or denying claims for such visits using retrospective claims algorithms. Low-income Black and Hispanic pediatric patients often experience worse access to primary care services necessary for preventing some ED visits, raising concerns about the uneven impact of these policies. Objective To estimate potential racial and ethnic disparities in outcomes of Medicaid policies for reducing ED professional reimbursement based on a retrospective diagnosis-based claims algorithm. Design, Setting, and Participants This simulation study used a retrospective cohort of pediatric ED visits (aged 0-18 years) for Medicaid-insured children and adolescents appearing in the Market Scan Medicaid database between January 1, 2016, and December 31, 2019. Visits missing date of birth, race and ethnicity, professional claims data, and Current Procedural Terminology codes of billing level of complexity were excluded, as were visits that result in admission. Data were analyzed from October 2021 to June 2022. Main Outcomes and Measures Proportion of ED visits algorithmically classified as nonemergent and simulated per-visit professional reimbursement after applying a current reimbursement reduction policy for potentially nonemergent ED visits. Rates were calculated overall and compared by race and ethnicity. Results The sample included 8 471 386 unique ED visits (43.0% by patients aged 4-12 years; 39.6% Black, 7.7% Hispanic, and 48.7% White), of which 47.7% were algorithmically identified as potentially nonemergent and subject to reimbursement reduction, resulting in a 37% reduction in ED professional reimbursement across the study cohort. More visits by Black (50.3%) and Hispanic (49.0%) children were algorithmically identified as nonemergent when compared with visits by White children (45.3%; P < .001). Modeling the impact of the reimbursement reductions across the cohort resulted in expected per-visit reimbursement that was 6% lower for visits by Black children and 3% lower for visits by Hispanic children relative to visits by White children. Conclusions and Relevance In this simulation study of over 8 million unique ED visits, algorithmic approaches for classifying pediatric ED visits that used diagnosis codes identified proportionately more visits by Black and Hispanic children as nonemergent. Insurers applying financial adjustments based on these algorithmic outputs risk creating uneven reimbursement policies across racial and ethnic groups.
Collapse
Affiliation(s)
- Alexander Pomerantz
- Department of Pediatrics, Boston Children’s Hospital, Boston, Massachusetts
- Department of Pediatrics, Boston Medical Center, Boston, Massachusetts
| | | | | | - Mark I. Neuman
- Division of Emergency Medicine, Boston Children’s Hospital, Boston, Massachusetts
| | - Monika K. Goyal
- Department of Pediatrics, Children’s National Hospital, George Washington University, Washington, DC
| | | | - Paul L. Aronson
- Department of Pediatrics, Yale School of Medicine, New Haven, Connecticut
- Department of Emergency Medicine, Yale School of Medicine, New Haven, Connecticut
| | - Elizabeth R. Alpern
- Division of Emergency Medicine, Department of Pediatrics, Ann & Robert H. Lurie Children’s Hospital of Chicago, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Harold K. Simon
- Department of Pediatrics, Emory University School of Medicine and Children’s Healthcare of Atlanta, Atlanta, Georgia
| | - Jennifer A. Hoffmann
- Division of Emergency Medicine, Department of Pediatrics, Ann & Robert H. Lurie Children’s Hospital of Chicago, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Jordee M. Wells
- Division of Emergency Medicine, Department of Pediatrics, Nationwide Children’s Hospital, The Ohio State University College of Medicine, Columbus
| | - Kristen H. Shanahan
- Division of Emergency Medicine, Boston Children’s Hospital, Boston, Massachusetts
| | - Colleen K. Gutman
- Department of Emergency Medicine, University of Florida, Gainesville
- Department of Pediatrics, University of Florida, Gainesville
| | - Alon Peltz
- Department of Pediatrics, Boston Children’s Hospital, Boston, Massachusetts
- Department of Population Medicine, Harvard Medical School, Harvard Pilgrim Health Care Institute, Boston, Massachusetts
| |
Collapse
|
4
|
Onwuka AJ, Knaus ME, Lawrence AE, Sebastião YV, Wells JM, Stoner MJ, Hewitt G, Deans KJ, Minneci PC. Comparing the Evaluation of Abdominal Pain in Adolescent Females at a Pediatric vs General Emergency Department. J Pediatr Adolesc Gynecol 2022; 35:562-566. [PMID: 35430344 DOI: 10.1016/j.jpag.2022.04.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 02/16/2022] [Accepted: 04/04/2022] [Indexed: 10/18/2022]
Abstract
BACKGROUND The objective of this study was to determine the rates at which gynecologic history and related exams are performed among adolescent females presenting with abdominal pain and whether the rates differ between patients seeking care at a pediatric compared with a general emergency department (ED). METHODS We conducted a retrospective cohort study of female patients aged 12-21 years who presented to the ED for a chief complaint of abdominal pain at either a single academic children's ED or a single general academic ED during 2016. We examined differences in the rates of gynecologic history and related exams between institutions, before and after adjustment with inverse probability weights. RESULTS A total of 837 females met the inclusion criteria for this study, and 627 patients were included in the adjusted analyses. Outcomes more commonly performed at the pediatric institution included documentation of contraception (28% at the general ED vs 43% at the pediatric ED, P < .001), sexually transmitted infection testing (32% at the general ED vs 42% at the pediatric ED, P = .04), and radiologic imaging (46% at the general ED vs 70% at the pediatric ED, P < .001). Outcomes that were more commonly performed at the general ED were pelvic exam (26% at the general ED vs 10% at the pediatric ED, P < .001) and complete blood count draw (67% at the general ED vs 39% at the pediatric ED, P < .001). No differences were observed between institutions in the documentation of menarche or sexual activity, the performance of a pregnancy test or CT scan, or the rate of subsequent ED/urgent care visits in the following year. CONCLUSION The rates at which gynecologic history and pelvic examination were performed in adolescent females presenting for abdominal pain at both a general ED and a pediatric ED were low and inconsistent. Providers should have a low threshold for testing for sexually transmitted infections and pregnancy. Pelvic examination and diagnostic lab testing should be performed when indicated in the setting of a clinically appropriate history. These efforts would ensure adequate evaluation of adolescent women and reduce unnecessary health resource utilization.
Collapse
Affiliation(s)
- Amanda J Onwuka
- Center for Surgical Outcomes Research, Abigail Wexner Research Institute, Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH 43205, United States
| | - Maria E Knaus
- Center for Surgical Outcomes Research, Abigail Wexner Research Institute, Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH 43205, United States; Department of Surgery, Division of Pediatric Surgery, The Ohio State University College of Medicine, Nationwide Children's Hospital, Columbus, Ohio
| | - Amy E Lawrence
- Department of Surgery, Division of General Surgery, The University of Rochester, Rochester, New York
| | - Yuri V Sebastião
- Division of Global Women's Health, Department of Obstetrics and Gynecology, UNC School of Medicine, Chapel Hill, North Carolina
| | - Jordee M Wells
- Center for Child Health Equity and Outcomes Research, Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, OH; Department of Pediatrics, Division of Emergency Medicine, The Ohio State University College of Medicine, Nationwide Children's Hospital, Columbus, OH
| | - Michael J Stoner
- Department of Pediatrics, Division of Emergency Medicine, The Ohio State University College of Medicine, Nationwide Children's Hospital, Columbus, OH
| | - Geri Hewitt
- Department of Surgery, Division of Pediatric and Adolescent Gynecology, The Ohio State University College of Medicine, Nationwide Children's Hospital, Columbus, OH
| | - Katherine J Deans
- Center for Surgical Outcomes Research, Abigail Wexner Research Institute, Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH 43205, United States; Department of Surgery, Division of Pediatric Surgery, The Ohio State University College of Medicine, Nationwide Children's Hospital, Columbus, Ohio
| | - Peter C Minneci
- Center for Surgical Outcomes Research, Abigail Wexner Research Institute, Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH 43205, United States; Department of Surgery, Division of Pediatric Surgery, The Ohio State University College of Medicine, Nationwide Children's Hospital, Columbus, Ohio.
| |
Collapse
|
5
|
Wells JM, Rodean J, Cook L, Sills MR, Neuman MI, Kornblith AE, Jain S, Hirsch AW, Goyal MK, Fleegler EW, DeLaroche AM, Aronson PL, Leonard JC. Injury-Related Pediatric Emergency Department Visits in the First Year of COVID-19. Pediatrics 2022; 150:188520. [PMID: 35836331 DOI: 10.1542/peds.2021-054545] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/17/2022] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVES To describe the epidemiology of pediatric injury-related visits to children's hospital emergency departments (EDs) in the United States during early and later periods of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. METHODS We conducted a cross-sectional study using the Pediatric Health Information System, an administrative database to identify injury-related ED visits at 41 United States children's hospitals during the SARS-CoV-2 pandemic period (March 15, 2020 to March 14, 2021) and a 3 year comparator period (March 15-March 14, 2017-2020). For these 2 periods, we compared patient characteristics, injury type and severity, primary discharge diagnoses, and disposition, stratified by early (March 15, 2020 to June 30, 2020), middle (July 1, 2020 to October 31, 2020), and late (November 1, 2020 to March 14, 2021) pandemic periods. RESULTS Overall, ED injury-related visits decreased by 26.6% during the first year of the SARS-CoV-2 pandemic, with the largest decline observed in minor injuries. ED injury-related visits resulting in serious-critical injuries increased across the pandemic (15.9% early, 4.9% middle, 20.6% late). Injury patterns with the sharpest relative declines included superficial injuries (41.7% early) and sprains/strains (62.4% early). Mechanisms of injury with the greatest relative increases included (1) firearms (22.9% early; 42.8% middle; 37% late), (2) pedal cyclists (60.4%; 24.9%; 32.2%), (3) other transportation (20.8%; 25.3%; 17.9%), and (4) suffocation/asphyxiation (21.4%; 20.2%; 28.4%) and injuries because of suicide intent (-16.2%, 19.9%, 21.8%). CONCLUSIONS Pediatric injury-related ED visits declined in general. However, there was a relative increase in injuries with the highest severity, which warrants further investigation.
Collapse
Affiliation(s)
- Jordee M Wells
- Department of Pediatrics, Division of Emergency Medicine, Nationwide Children's Hospital, The Ohio State University College of Medicine, Columbus, Ohio
| | | | - Lawrence Cook
- Department of Pediatrics, School of Medicine, The University of Utah, Salt Lake City, Utah
| | - Marion R Sills
- Department of Pediatrics, Section of Emergency Medicine, University of Colorado School of Medicine, Aurora, Colorado
| | - Mark I Neuman
- Division of Emergency Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Aaron E Kornblith
- Departments of Emergency Medicine and Pediatrics, University of California San Francisco, San Francisco, California
| | - Shobhit Jain
- Department of Pediatrics, Division of Pediatric Emergency Medicine, Children's Mercy Hospital, Kansas City, Missouri
| | - Alexander W Hirsch
- Division of Emergency Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Monika K Goyal
- Department of Pediatrics, Children's National Hospital, The George Washington University, Washington, District of Columbia
| | - Eric W Fleegler
- Division of Emergency Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Amy M DeLaroche
- Department of Pediatrics, Division of Pediatric Emergency Medicine, Children's Hospital of Michigan, Detroit, Michigan
| | - Paul L Aronson
- Departments of Pediatrics and of Emergency Medicine, Section of Pediatric Emergency Medicine, Yale School of Medicine, New Haven, Connecticut
| | - Julie C Leonard
- Department of Pediatrics, Division of Emergency Medicine, Nationwide Children's Hospital, The Ohio State University College of Medicine, Columbus, Ohio
| |
Collapse
|
6
|
Wells JM, Galarneau JM, Minich NM, Cohen DM, Clinton K, Taylor HG, Bigler ED, Bacevice A, Mihalov LK, Bangert BA, Zumberge NA, Yeates KO. Social determinants of participant recruitment and retention in a prospective cohort study of pediatric mild traumatic brain injury. Front Neurol 2022; 13:961024. [PMID: 36176559 PMCID: PMC9513452 DOI: 10.3389/fneur.2022.961024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 08/23/2022] [Indexed: 11/13/2022] Open
Abstract
BackgroundPrior studies have shown poor recruitment and retention of minoritized groups in clinical trials.ObjectiveTo examine several social determinants as predictors of consent to participate and retention as part of a prospective, longitudinal cohort study of children 8–16 with either mild traumatic brain injury (mild TBI) or orthopedic injury (OI).MethodsChildren and families were recruited during acute visits to emergency departments (ED) in two large children's hospitals in the midwestern United States for a prospective, longitudinal cohort study of children 8–16 with either mild TBI or OI.ResultsA total of 588 (mild TBI = 307; OI = 281) eligible children were approached in the ED and 315 (mild TBI = 195; OI = 120) were consented. Children who consented did not differ significantly from those who did not consent in sex or age. Consent rates were higher among Black (60.9%) and multi-racial (76.3%) children than white (45.3%) children. Among the 315 children who consented, 217 returned for a post-acute assessment (mild TBI = 143; OI = 74), a retention rate of 68.9%. Participants who were multi-racial (96.6%) or white (79.8%) were more likely to return for the post-acute visit than those who were Black (54.3%).ConclusionsRacial differences exist in both recruitment and retention of participants in a prospective, longitudinal cohort of children with mild TBI or OI. Further work is needed to understand these differences to ensure equitable participation of minoritized groups in brain injury research.
Collapse
Affiliation(s)
- Jordee M. Wells
- Department of Pediatrics, Abigail Wexner Research Institute at Nationwide Children's Hospital, The Ohio State University, Columbus, OH, United States
- *Correspondence: Jordee M. Wells
| | - Jean-Michel Galarneau
- Department of Psychology, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
| | - Nori M. Minich
- Department of Pediatrics, Rainbow Babies and Children's Hospital, Case Western Reserve University, Cleveland, OH, United States
| | - Daniel M. Cohen
- Department of Pediatrics, Abigail Wexner Research Institute at Nationwide Children's Hospital, The Ohio State University, Columbus, OH, United States
| | - Kameron Clinton
- Department of Pediatrics, Abigail Wexner Research Institute at Nationwide Children's Hospital, The Ohio State University, Columbus, OH, United States
| | - H. Gerry Taylor
- Department of Pediatrics, Abigail Wexner Research Institute at Nationwide Children's Hospital, The Ohio State University, Columbus, OH, United States
| | - Erin D. Bigler
- Department of Psychology and Neuroscience Center, Brigham Young University, Provo, UT, United States
| | - Ann Bacevice
- Department of Pediatrics, Rainbow Babies and Children's Hospital, Case Western Reserve University, Cleveland, OH, United States
| | - Leslie K. Mihalov
- Department of Pediatrics, Abigail Wexner Research Institute at Nationwide Children's Hospital, The Ohio State University, Columbus, OH, United States
| | - Barbara A. Bangert
- Departments of Radiology and Neurosurgery, University Hospitals Health System, Cleveland, OH, United States
| | - Nicholas A. Zumberge
- Department of Radiology, Nationwide Children's Hospital, Columbus, OH, United States
| | - Keith Owen Yeates
- Department of Psychology, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
| |
Collapse
|
7
|
Wells JM, Shi J, Bonny AE, Leonard JC. The Association of Emergency Contraception Legislation with Adolescent Births from 2000 to 2014. J Pediatr Adolesc Gynecol 2022; 35:462-466. [PMID: 35124213 DOI: 10.1016/j.jpag.2022.01.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 01/25/2022] [Accepted: 01/28/2022] [Indexed: 10/19/2022]
Abstract
STUDY OBJECTIVE The objective of the study was to examine the association of state-specific emergency contraception (EC) legislation and adolescent births. DESIGN, SETTING, AND PARTICIPANTS This was an observational cohort study of adolescents aged 15-19 years in the United States from 2000 through 2014 to determine the association of adolescent birth estimates with EC legislation. MAIN OUTCOME MEASURES State-specific birth and abortion estimate data were obtained from the Centers for Disease Control and Prevention's National Vital Statistics and Abortion Surveillance for the years 2000 through 2014. RESULTS After controlling for year, abortion estimates, and oral contraception pill utilization, estimated adolescent births for states with an expansive EC policy was 14% lower as compared with states without an expansive policy. Estimated adolescent births were 43% higher in states with a restrictive EC policy as compared with states without a restrictive policy. CONCLUSION Restrictive EC policies are associated with increased adolescent birth estimates, whereas expansive EC policies are associated with decreased adolescent birth estimates. Targeted advocacy strategies to reduce legislation that aims to restrict access to contraception may prove to be most beneficial to reducing unintended pregnancies.
Collapse
Affiliation(s)
- Jordee M Wells
- Department of Pediatrics, Division of Emergency Medicine, Nationwide Children's Hospital, 700 Children's Drive, Columbus, Ohio 43205; Center for Child Health Equity and Outcomes Research, The Abigail Wexner Research Institute at Nationwide Children's Hospital, 700 Children's Drive, Columbus, Ohio 43205; The Ohio State University College of Medicine, 370 W 9th Avenue, Columbus, Ohio 43210.
| | - Junxin Shi
- Center for Injury Research and Policy, The Abigail Wexner Research Institute at Nationwide Children's Hospital, 700 Children's Drive, Columbus, Ohio 43205
| | - Andrea E Bonny
- The Ohio State University College of Medicine, 370 W 9th Avenue, Columbus, Ohio 43210; Department of Pediatrics, Division of Adolescent Medicine, Nationwide Children's Hospital, 700 Children's Drive, Columbus, Ohio 43205; Center for Clinical and Translational Research, The Abigail Wexner Research Institute at Nationwide Children's Hospital, 700 Children's Drive, Columbus, Ohio 43205
| | - Julie C Leonard
- Department of Pediatrics, Division of Emergency Medicine, Nationwide Children's Hospital, 700 Children's Drive, Columbus, Ohio 43205; The Ohio State University College of Medicine, 370 W 9th Avenue, Columbus, Ohio 43210; Center for Injury Research and Policy, The Abigail Wexner Research Institute at Nationwide Children's Hospital, 700 Children's Drive, Columbus, Ohio 43205
| |
Collapse
|
8
|
Pistenmaa CL, Nardelli P, Ash SY, Come CE, Diaz AA, Rahaghi FN, Barr RG, Young KA, Kinney GL, Simmons JP, Wade RC, Wells JM, Hokanson JE, Washko GR, San José Estépar R. Pulmonary Arterial Pruning and Longitudinal Change in Percent Emphysema and Lung Function: The Genetic Epidemiology of COPD Study. Chest 2021; 160:470-480. [PMID: 33607083 PMCID: PMC8411454 DOI: 10.1016/j.chest.2021.01.084] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 12/28/2020] [Accepted: 01/23/2021] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Pulmonary endothelial damage has been shown to precede the development of emphysema in animals, and vascular changes in humans have been observed in COPD and emphysema. RESEARCH QUESTION Is intraparenchymal vascular pruning associated with longitudinal progression of emphysema on CT imaging or decline in lung function over 5 years? STUDY DESIGN AND METHODS The Genetic Epidemiology of COPD Study enrolled ever smokers with and without COPD from 2008 through 2011. The percentage of emphysema-like lung, or "percent emphysema," was assessed at baseline and after 5 years on noncontrast CT imaging as the percentage of lung voxels < -950 Hounsfield units. An automated CT imaging-based tool assessed and classified intrapulmonary arteries and veins. Spirometry measures are postbronchodilator. Pulmonary arterial pruning was defined as a lower ratio of small artery volume (< 5 mm2 cross-sectional area) to total lung artery volume. Mixed linear models included demographics, anthropomorphics, smoking, and COPD, with emphysema models also adjusting for CT imaging scanner and lung function models adjusting for clinical center and baseline percent emphysema. RESULTS At baseline, the 4,227 participants were 60 ± 9 years of age, 50% were women, 28% were Black, 47% were current smokers, and 41% had COPD. Median percent emphysema was 2.1 (interquartile range, 0.6-6.3) and progressed 0.24 percentage points/y (95% CI, 0.22-0.26 percentage points/y) over 5.6 years. Mean FEV1 to FVC ratio was 68.5 ± 14.2% and declined 0.26%/y (95% CI, -0.30 to -0.23%/y). Greater pulmonary arterial pruning was associated with more rapid progression of percent emphysema (0.11 percentage points/y per 1-SD increase in arterial pruning; 95% CI, 0.09-0.16 percentage points/y), including after adjusting for baseline percent emphysema and FEV1. Arterial pruning also was associated with a faster decline in FEV1 to FVC ratio (-0.04%/y per 1-SD increase in arterial pruning; 95% CI, -0.008 to -0.001%/y). INTERPRETATION Pulmonary arterial pruning was associated with faster progression of percent emphysema and more rapid decline in FEV1 to FVC ratio over 5 years in ever smokers, suggesting that pulmonary vascular differences may be relevant in disease progression. TRIAL REGISTRY ClinicalTrials.gov; No.: NCT00608764; URL: www.clinicaltrials.gov.
Collapse
Affiliation(s)
| | - P Nardelli
- Department of Radiology, Brigham and Women's Hospital, Boston, MA
| | - S Y Ash
- Department of Medicine, Brigham and Women's Hospital, Boston, MA
| | - C E Come
- Department of Medicine, Brigham and Women's Hospital, Boston, MA
| | - A A Diaz
- Department of Medicine, Brigham and Women's Hospital, Boston, MA
| | - F N Rahaghi
- Department of Medicine, Brigham and Women's Hospital, Boston, MA
| | - R G Barr
- Departments of Medicine and Epidemiology, Columbia University, New York, NY
| | - K A Young
- Department of Epidemiology, Colorado School of Public Health, University of Colorado, Denver, CO
| | - G L Kinney
- Department of Epidemiology, Colorado School of Public Health, University of Colorado, Denver, CO
| | - J P Simmons
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL
| | - R C Wade
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL
| | - J M Wells
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL
| | - J E Hokanson
- Department of Epidemiology, Colorado School of Public Health, University of Colorado, Denver, CO
| | - G R Washko
- Department of Medicine, Brigham and Women's Hospital, Boston, MA
| | | |
Collapse
|
9
|
Wells JM, Stanley R. Advocating for Minority Inclusion in Clinical Trials: A Call for Representation and Justice. Pediatrics 2021; 147:peds.2021-049937. [PMID: 33846236 DOI: 10.1542/peds.2021-049937] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/25/2021] [Indexed: 11/24/2022] Open
Affiliation(s)
- Jordee M Wells
- Nationwide Children's Hospital, Columbus, Ohio; and .,Department of Pediatrics, College of Medicine, The Ohio State University, Columbus, Ohio
| | - Rachel Stanley
- Nationwide Children's Hospital, Columbus, Ohio; and.,Department of Pediatrics, College of Medicine, The Ohio State University, Columbus, Ohio
| |
Collapse
|
10
|
DeLaroche AM, Rodean J, Aronson PL, Fleegler EW, Florin TA, Goyal M, Hirsch AW, Jain S, Kornblith AE, Sills MR, Wells JM, Neuman MI. Pediatric Emergency Department Visits at US Children's Hospitals During the COVID-19 Pandemic. Pediatrics 2021; 147:peds.2020-039628. [PMID: 33361360 DOI: 10.1542/peds.2020-039628] [Citation(s) in RCA: 140] [Impact Index Per Article: 46.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/18/2020] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND AND OBJECTIVES The impact of the coronavirus disease 2019 (COVID-19) pandemic on pediatric emergency department (ED) visits is not well characterized. We aimed to describe the epidemiology of pediatric ED visits and resource use during the pandemic. METHODS We conducted a cross-sectional study using the Pediatric Health Information System for ED visits to 27 US children's hospitals during the COVID-19 pandemic period (March 15, 2020, to August 31, 2020) and a 3-year comparator period (March 15 to August 31, 2017-2019). ED visit rates, patient and visit characteristics, resource use, and ED charges were compared between the time periods. We specifically evaluated changes in low-resource-intensity visits, defined as ED visits that did not result in hospitalization or medication administration and for which no laboratory tests, diagnostic imaging, or procedures were performed. RESULTS ED visit rates decreased by 45.7% (average 911 026 ED visits over 2017-2019 vs 495 052 visits in 2020) during the pandemic. The largest decrease occurred among visits for respiratory disorders (70.0%). The pandemic was associated with a relative increase in the proportion of visits for children with a chronic condition from 23.7% to 27.8% (P < .001). The proportion of low-resource-intensity visits decreased by 7.0 percentage points, and total charges decreased by 20.0% during the pandemic period. CONCLUSIONS The COVID-19 pandemic was associated with a marked decrease in pediatric ED visits across a broad range of conditions; however, the proportional decline of poisoning and mental health visits was less pronounced. The impact of decreased visits on patient outcomes warrants further research.
Collapse
Affiliation(s)
- Amy M DeLaroche
- Division of Pediatric Emergency Medicine, Department of Pediatrics, Children's Hospital of Michigan, Detroit, Michigan;
| | | | - Paul L Aronson
- Section of Pediatric Emergency Medicine, Departments of Pediatrics and Emergency Medicine, Yale School of Medicine, Yale University, New Haven, Connecticut
| | - Eric W Fleegler
- Department of Pediatrics, Boston Children's Hospital and Harvard Medical School, Harvard University, Boston, Massachusetts
| | - Todd A Florin
- Division of Pediatric Emergency Medicine, Ann and Robert H. Lurie Children's Hospital of Chicago and Department of Pediatrics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Monika Goyal
- Department of Pediatrics, Children's National Hospital and The George Washington University, Washington, District of Columbia
| | - Alexander W Hirsch
- Department of Pediatrics, Boston Children's Hospital and Harvard Medical School, Harvard University, Boston, Massachusetts
| | - Shobhit Jain
- Division of Pediatric Emergency Medicine, Department of Pediatrics, Children's Mercy Hospital, Kansas City, Missouri
| | - Aaron E Kornblith
- Division of Emergency Medicine, Department of Pediatrics, University of California San Francisco, San Francisco, California
| | - Marion R Sills
- Division of Pediatric Emergency Medicine, Department of Pediatrics, Children's Hospital of Colorado, Aurora, Colorado; and
| | - Jordee M Wells
- Division of Emergency Medicine, Department of Pediatrics, Nationwide Children's Hospital, College of Medicine, The Ohio State University Columbus, Ohio
| | - Mark I Neuman
- Department of Pediatrics, Boston Children's Hospital and Harvard Medical School, Harvard University, Boston, Massachusetts
| |
Collapse
|
11
|
van Splunter M, van Hoffen E, Floris-Vollenbroek EG, Timmerman H, de Bos ELV, Meijer B, Ulfman LH, Witteman B, Wells JM, Brugman S, Savelkoul HFJ, van Neerven RJJ. Oral cholera vaccination promotes homing of IgA + memory B cells to the large intestine and the respiratory tract. Mucosal Immunol 2018; 11:1254-1264. [PMID: 29467446 DOI: 10.1038/s41385-018-0006-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 12/22/2017] [Accepted: 01/09/2018] [Indexed: 02/04/2023]
Abstract
Oral cholera vaccination is used to induce immune responses in the intestines to protect against cholera infection. However, oral vaccination may also affect immune responses in other mucosal tissues. To study this, tissue-specific homing potential and kinetics of B-cell responses were characterized after oral cholera vaccination. Healthy adult volunteers received two doses of Dukoral® and blood, saliva, nasal wash, and fecal samples were collected over time to detect vaccine-specific antibodies. Additionally, homing potential of lymphocytes to small intestine, colon, airways, skin, and periphery was measured by expression of Integrin β1 and β7, CCR9, CCR10, CCR7, and CLA. After vaccination, antibody responses to cholera toxin B (CTB) and Dukoral® were detected in serum and nasal wash. CTB-specific memory B cells in peripheral blood and tissue homing profiles of memory B cells peaked at day 18. IgA+ memory B cells expressed markers that enable homing to the airways and colon, while IgA- memory B cells primarily expressed small-intestine-homing markers. These data show that oral cholera vaccination has a differential effect on immune responses in various mucosal sites, including the respiratory tract.
Collapse
Affiliation(s)
- M van Splunter
- Cell Biology and Immunology, Wageningen University, Wageningen, The Netherlands
| | | | | | | | | | - B Meijer
- Cell Biology and Immunology, Wageningen University, Wageningen, The Netherlands
| | - L H Ulfman
- FrieslandCampina, Amersfoort, The Netherlands
| | - B Witteman
- Human Nutrition, Wageningen University, Wageningen, The Netherlands.,Ziekenhuis Gelderse Vallei, Ede, The Netherlands
| | - J M Wells
- Host Microbe Interactomics, Wageningen University, Wageningen, The Netherlands
| | - S Brugman
- Cell Biology and Immunology, Wageningen University, Wageningen, The Netherlands
| | - H F J Savelkoul
- Cell Biology and Immunology, Wageningen University, Wageningen, The Netherlands
| | - R J J van Neerven
- Cell Biology and Immunology, Wageningen University, Wageningen, The Netherlands. .,FrieslandCampina, Amersfoort, The Netherlands.
| |
Collapse
|
12
|
Honoré C, Rescan C, Hald J, McGrath PS, Petersen MBK, Hansson M, Klein T, Østergaard S, Wells JM, Madsen OD. Revisiting the immunocytochemical detection of Neurogenin 3 expression in mouse and man. Diabetes Obes Metab 2016; 18 Suppl 1:10-22. [PMID: 27615127 DOI: 10.1111/dom.12718] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 05/08/2016] [Indexed: 12/13/2022]
Abstract
During embryonic development, endocrine cells of the pancreas are specified from multipotent progenitors. The transcription factor Neurogenin 3 (NEUROG3) is critical for this development and it has been shown that all endocrine cells of the pancreas arise from endocrine progenitors expressing NEUROG3. A thorough understanding of the role of NEUROG3 during development, directed differentiation of pluripotent stem cells and in models of cellular reprogramming, will guide future efforts directed at finding novel sources of β-cells for cell replacement therapies. In this article, we review the expression and function of NEUROG3 in both mouse and human and present the further characterization of a monoclonal antibody directed against NEUROG3. This antibody has been previously been used for detection of both mouse and human NEUROG3. However, our results suggest that the epitope recognized by this antibody is specific to mouse NEUROG3. Thus, we have also generated a monoclonal antibody specifically recognizing human NEUROG3 and present the characterization of this antibody here. Together, these antibodies will provide useful tools for future studies of NEUROG3 expression, and the data presented in this article suggest that recently described expression patterns of NEUROG3 in human foetal and adult pancreas should be re-examined.
Collapse
Affiliation(s)
- C Honoré
- Department of Islet and Stem Cell Biology, Novo Nordisk A/S, Måløv, Denmark.
| | - C Rescan
- Department of Islet and Stem Cell Biology, Novo Nordisk A/S, Måløv, Denmark
| | - J Hald
- Department of Islet and Stem Cell Biology, Novo Nordisk A/S, Måløv, Denmark
| | - P S McGrath
- Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - M B K Petersen
- Department of Islet and Stem Cell Biology, Novo Nordisk A/S, Måløv, Denmark
| | - M Hansson
- Department of Islet and Stem Cell Biology, Novo Nordisk A/S, Måløv, Denmark
| | - T Klein
- Gubra Aps, Agern Alle 1, Hørsholm, Denmark
| | - S Østergaard
- Department of Islet and Stem Cell Biology, Novo Nordisk A/S, Måløv, Denmark
| | - J M Wells
- Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
- Division of Endocrinology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - O D Madsen
- Department of Islet and Stem Cell Biology, Novo Nordisk A/S, Måløv, Denmark
| |
Collapse
|
13
|
Moawad FJ, Wells JM, Johnson RL, Reinhardt BJ, Maydonovitch CL, Baker TP. Comparison of eotaxin-3 biomarker in patients with eosinophilic oesophagitis, proton pump inhibitor-responsive oesophageal eosinophilia and gastro-oesophageal reflux disease. Aliment Pharmacol Ther 2015; 42:231-8. [PMID: 26011446 DOI: 10.1111/apt.13258] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Revised: 04/20/2015] [Accepted: 05/04/2015] [Indexed: 12/19/2022]
Abstract
BACKGROUND Proton pump inhibitor-responsive oesophageal eosinophilia (PPI-REE) is a recently described entity which resembles oeosinophilic oesophagitis (EoE), yet responds to acid suppressive treatment. AIM To determine whether EoE shares similar staining features with PPI-REE or with gastro-oesophageal reflux disease (GERD). METHODS This retrospective study consisted of patients with an established diagnosis of EoE, PPI-REE, or GERD identified from a database during a 1-year period. Immunohistochemistry (IHC) analysis was performed specifically targeting eotaxin-3 antibodies. All sections were qualitatively (intensity) and quantitatively (percentage of cells stained) assessed independently by two blinded pathologists. RESULTS The cohort consisted of three groups of patients: EoE (n = 22), PPI-REE (n = 23) and GERD (n = 23) for a total of 68 patients. Study demographics included mean age 39 (14) years, 75% male and 77% Caucasian. There was a significant difference in the eotaxin-3 staining among EoE, PPI-REE and GERD groups [mean score (s.d.): 1.2 (1.2), 0.8 (1.0), 0.3 (0.7), P = 0.006]. Staining scores of EoE patients were significantly higher compared with GERD (P = 0.002) and a trend towards significance was seen between EoE and PPI-REE (P = 0.054). There was also a significant difference in EoE staining intensity score among the three groups (P = 0.006). Intensity scores of EoE were significantly higher compared with GERD [1.0 (0.9) vs. 0.22 (0.52), P < 0.001]. There was no significant difference between EoE and PPI-REE groups [1.0 (0.0) vs. 0.52 (0.75) P = 0.094]. CONCLUSIONS A difference in eotaxin-3 staining was seen in the three groups of patients with oesophageal eosinophilia. Eotaxin-3 can distinguish EoE from GERD, but not from proton pump inhibitor responsive-oesophageal eosinophilia.
Collapse
Affiliation(s)
- F J Moawad
- Gastroenterology Service, Walter Reed National Military Medical Center, Bethesda, MD, USA
| | - J M Wells
- Department of Pathology, Walter Reed National Military Medical Center, Bethesda, MD, USA
| | - R L Johnson
- Department of Pathology, Walter Reed National Military Medical Center, Bethesda, MD, USA
| | - B J Reinhardt
- Department of Research Programs, Walter Reed National Military Medical Center, Bethesda, MD, USA
| | - C L Maydonovitch
- Gastroenterology Service, Walter Reed National Military Medical Center, Bethesda, MD, USA
| | - T P Baker
- Department of Pathology, Walter Reed National Military Medical Center, Bethesda, MD, USA
| |
Collapse
|
14
|
Loonen LMP, Stolte EH, Jaklofsky MTJ, Meijerink M, Dekker J, van Baarlen P, Wells JM. REG3γ-deficient mice have altered mucus distribution and increased mucosal inflammatory responses to the microbiota and enteric pathogens in the ileum. Mucosal Immunol 2014; 7:939-47. [PMID: 24345802 DOI: 10.1038/mi.2013.109] [Citation(s) in RCA: 129] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Accepted: 11/05/2013] [Indexed: 02/04/2023]
Abstract
REG3γ is considered to have a protective role against infection with Gram-positive bacteria due to its bactericidal activity, but evidence from in vivo studies is lacking. We generated a REG3γ(-/-) mouse, and investigated the effect of lack of REG3γ on intestinal mucus distribution, spatial compartmentalization of bacteria, and expression of innate immunity genes. Infection studies were also performed with Gram-positive and Gram-negative pathogens to investigate the antimicrobial role of REG3γ. REG3γ(-/-) mice display altered mucus distribution, increased bacterial contact with the epithelium, and elevated inflammatory markers in the ileum without histological evidence of pathology. Infection response pathway genes were differentially expressed in both Listeria monocytogenes and Salmonella enteritidis infected REG3γ(-/-) and wild-type (wt) mice. Higher amounts of myeloperoxidase and interleukin-22 transcripts were present in the ileal mucosa of REG3γ(-/-) than wt mice, but translocation to the organs was unaffected. We concluded that REG3γ has a protective role against mucosal infection with pathogenic Listeria and Salmonella in vivo. REG3γ is equally distributed throughout the mucus and its absence results in increased epithelial contact with the microbiota resulting in low-grade inflammation. REG3γ can bind to Gram-negative and Gram-positive bacteria and influence mucus distribution in the ileum, properties which may contribute to mucosal protection.
Collapse
Affiliation(s)
- L M P Loonen
- 1] TI Food and Nutrition, Wageningen, The Netherlands [2] Host-Microbe Interactomics group, Department of Animal Sciences, Wageningen University, Wageningen, The Netherlands
| | - E H Stolte
- Host-Microbe Interactomics group, Department of Animal Sciences, Wageningen University, Wageningen, The Netherlands
| | - M T J Jaklofsky
- Host-Microbe Interactomics group, Department of Animal Sciences, Wageningen University, Wageningen, The Netherlands
| | - M Meijerink
- Host-Microbe Interactomics group, Department of Animal Sciences, Wageningen University, Wageningen, The Netherlands
| | - J Dekker
- TI Food and Nutrition, Wageningen, The Netherlands
| | - P van Baarlen
- Host-Microbe Interactomics group, Department of Animal Sciences, Wageningen University, Wageningen, The Netherlands
| | - J M Wells
- 1] TI Food and Nutrition, Wageningen, The Netherlands [2] Host-Microbe Interactomics group, Department of Animal Sciences, Wageningen University, Wageningen, The Netherlands
| |
Collapse
|
15
|
Miquel S, Martín R, Rossi O, Bermúdez-Humarán LG, Chatel JM, Sokol H, Thomas M, Wells JM, Langella P. Faecalibacterium prausnitzii and human intestinal health. Curr Opin Microbiol 2013; 16:255-61. [DOI: 10.1016/j.mib.2013.06.003] [Citation(s) in RCA: 633] [Impact Index Per Article: 57.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Revised: 06/11/2013] [Accepted: 06/11/2013] [Indexed: 12/12/2022]
|
16
|
Hudcovic T, Kolinska J, Klepetar J, Stepankova R, Rezanka T, Srutkova D, Schwarzer M, Erban V, Du Z, Wells JM, Hrncir T, Tlaskalova-Hogenova H, Kozakova H. Protective effect of Clostridium tyrobutyricum in acute dextran sodium sulphate-induced colitis: differential regulation of tumour necrosis factor-α and interleukin-18 in BALB/c and severe combined immunodeficiency mice. Clin Exp Immunol 2012; 167:356-65. [PMID: 22236013 DOI: 10.1111/j.1365-2249.2011.04498.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
One of the promising approaches in the therapy of ulcerative colitis is administration of butyrate, an energy source for colonocytes, into the lumen of the colon. This study investigates the effect of butyrate producing bacterium Clostridium tyrobutyricum on dextran sodium sulphate (DSS)-induced colitis in mice. Immunocompetent BALB/c and immunodeficient severe combined immunodeficiency (SCID) mice reared in specific-pathogen-free (SPF) conditions were treated intrarectally with C. tyrobutyricum 1 week prior to the induction of DSS colitis and during oral DSS treatment. Administration of DSS without C. tyrobutyricum treatment led to an appearance of clinical symptoms - bleeding, rectal prolapses and colitis-induced increase in the antigen CD11b, a marker of infiltrating inflammatory cells in the lamina propria. The severity of colitis was similar in BALB/c and SCID mice as judged by the histological damage score and colon shortening after 7 days of DSS treatment. Both strains of mice also showed a similar reduction in tight junction (TJ) protein zonula occludens (ZO)-1 expression and of MUC-2 mucin depression. Highly elevated levels of cytokine tumour necrosis factor (TNF)-α in the colon of SCID mice and of interleukin (IL)-18 in BALB/c mice were observed. Intrarectal administration of C. tyrobutyricum prevented appearance of clinical symptoms of DSS-colitis, restored normal MUC-2 production, unaltered expression of TJ protein ZO-1 and decreased levels of TNF-α and IL-18 in the descending colon of SCID and BALB/c mice, respectively. Some of these features can be ascribed to the increased production of butyrate in the lumen of the colon and its role in protection of barrier functions and regulation of IL-18 expression.
Collapse
Affiliation(s)
- T Hudcovic
- Institute of Microbiology of Academy of Sciences of Czech Republic, v.v.i., Prague, Czech Republic
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
17
|
Wells JM, Raju BC, Nyland G, Lowe SK. Medium for isolation and growth of bacteria associated with plum leaf scald and phony peach diseases. Appl Environ Microbiol 2010; 42:357-63. [PMID: 16345835 PMCID: PMC244013 DOI: 10.1128/aem.42.2.357-363.1981] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Rickettsia-like bacteria associated with plum leaf scald and phony peach diseases were isolated from diseased but not from healthy tissues and cultured on charcoal-yeast extract medium (BCYE) buffered with ACES (2-[(2-amino-2-oxoethyl) amino]-ethanesulfonic acid). Optimum conditions for isolation and growth on BCYE medium were pH 6.5 to 6.9 at 20 and 25 degrees C under normal atmosphere. Growth of primary colonies and first-passage subcultures was restricted, and colonies reached a maximum diameter of 0.6 mm in 60 days. After 12 passages, subcultures reached maximum growth in 21 days. The rickettsia-like bacteria from BCYE cultures were gram negative, serologically the same as those present in diseased peach and plum, and composed of rod-shaped cells measuring 0.35 by 5 mum (average diameter and maximum length) in a matrix of filamentous strands of similar width but of variable length.
Collapse
Affiliation(s)
- J M Wells
- Southeastern Fruit and Tree Nut Research Laboratory, Science and Education Administration, U. S. Department of Agriculture, Byron, Georgia 31008
| | | | | | | |
Collapse
|
18
|
Wells JM, Mukerji S, Chandran H, Parashar K, McCarthy L. Urinomas protect renal function in posterior urethral valves--a population based study. J Pediatr Surg 2010; 45:407-10. [PMID: 20152362 DOI: 10.1016/j.jpedsurg.2009.10.084] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2009] [Accepted: 10/27/2009] [Indexed: 10/19/2022]
Abstract
BACKGROUND/PURPOSE Urinomas have been thought to protect renal function in boys with posterior urethral valves (PUVs), although recent reports have disputed this. This study tested the hypothesis that urinomas protect global renal function in boys with PUV. METHODS A retrospective analysis of all boys with PUV presenting to a tertiary unit derived from a region with an estimated population of 5.5 million was performed. Comparisons of the initial nadir creatinine, current creatinine, and renal status score (RSS) were made between those with and without urinomas. The RSS was derived from nephrology assessment of current renal status (0 = normal to 4 = end-stage renal failure or transplantation). Results were given as median (range), except for RSS, which was given as mean +/- SEM. P < or = .05 was regarded as significant. RESULTS During 1989-2009, 9 of 89 PUV boys were diagnosed with urinomas. Initial nadir creatinine was statistically lower in boys with urinomas (31 [18-44] vs 45 [20-574] mumol/L, P < .01). Length of follow-up was similar (5.1 [2.2-17.3] vs 5.9 [1.8-19.7] years, P = .59). Follow-up creatinine was significantly lower in urinoma boys (44 [25-77] vs 61 [29-1227] micromol/L, P < .05), as was the RSS (0.14 +/- 0.14 vs 0.91 +/- 0.14, P < .01). No urinoma boys progressed to end-stage renal failure or required transplant. CONCLUSION This population-based study of PUV boys demonstrates that urinomas reduce nadir creatinine and significantly protect long-term global renal function.
Collapse
Affiliation(s)
- J M Wells
- Department of Paediatric Urology, Birmingham Children's Hospital, UK
| | | | | | | | | |
Collapse
|
19
|
El Sahly HM, Atmar RL, Patel SM, Wells JM, Cate T, Ho M, Guo K, Pasetti MF, Lewis DE, Sztein MB, Keitel WA. Safety, reactogenicity and immunogenicity of Francisella tularensis live vaccine strain in humans. Vaccine 2009; 27:4905-11. [PMID: 19567246 PMCID: PMC2726995 DOI: 10.1016/j.vaccine.2009.06.036] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2009] [Revised: 06/05/2009] [Accepted: 06/09/2009] [Indexed: 11/16/2022]
Abstract
We evaluated the safety, reactogenicity and immunogenicity of escalating doses of a new Francisella tularensis Live Vaccine Strain (LVS) lot by scarification (SCAR) or subcutaneously (SQ) in humans. Subjects (N=10/group) received one dose of LVS via SCAR at 10(5),10(7) or 10(9)cfu/ml or SQ at 10(2), 10(3),10(4) or 10(5)cfu/ml; 14 subjects received placebo. All doses/routes were well tolerated. When compared to placebo, vaccination with 10(7) SCAR and 10(9) SCAR resulted in significantly higher serologic response frequencies, as measured by ELISA for IgG, IgM, IgA and microagglutination; whereas vaccination with 10(5) SCAR, 10(7) SCAR 10(9) SCAR and 10(5) SQ elicited a significantly higher interferon-gamma response frequency.
Collapse
Affiliation(s)
- H M El Sahly
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, United States.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Affiliation(s)
- J M Wells
- Department of Upper Gastrointestinal Surgery, Leeds GeneralInfirmary, Leeds, UK
| | | | | |
Collapse
|
21
|
Affiliation(s)
- JM Wells
- Department of Upper Gastrointestinal Surgery, Leeds General Infirmary Leeds, UK
| | - CM Pring
- Department of Upper Gastrointestinal Surgery, Leeds General Infirmary Leeds, UK
| | - SPL Dexter
- Department of Upper Gastrointestinal Surgery, Leeds General Infirmary Leeds, UK
| |
Collapse
|
22
|
Edwards GD, Shepson PB, Grossenbacher JW, Wells JM, Patterson GE, Barket DJ, Pressley S, Karl T, Apel E. Development of an Automated Cylindrical Ion Trap Mass Spectrometer for the Determination of Atmospheric Volatile Organic Compounds. Anal Chem 2007; 79:5040-50. [PMID: 17542557 DOI: 10.1021/ac0703597] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Volatile organic compounds released from the biosphere are known to have a large impact on atmospheric chemistry. Field instruments for the detection of these trace gases are often limited by the lack of instrument portability and the inability to distinguish compounds of interest from background or other interfering compounds. We have developed an automated sampling and preconcentration system, coupled to a lightweight, low-power cylindrical ion trap mass spectrometer. The instrument was evaluated by measuring isoprene concentrations during a field campaign at the University of Michigan Biological Station PROPHET lab. Isoprene was preconcentrated by sampling directly into a short capillary column precooled without the aid of cryogens. The capillary column was then rapidly heated by moving the column to a preheated region to obtain fast separation of isoprene from other components, followed by detection with a cylindrical ion trap. This combination yielded a detection limit of approximately 80 ppt (parts per trillion) for isoprene with a measurement frequency of one sample every 11 min. The data obtained by the automated sampling and preconcentration system during the PROPHET 2005 campaign were compared to those of other field instruments measuring isoprene at this site in an intercomparison exercise. The intercomparisons suggest the new inlet system, when coupled with this ion trap detector, provides a viable field instrument for the fast, precise, and quantitative determination of isoprene and other trace gases over a variety of atmospheric conditions.
Collapse
Affiliation(s)
- Gavin D Edwards
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
23
|
Affiliation(s)
- J M Wells
- Medical Policy and Audit (Army), Slim Road, Camberley, Surrey, GU15 4NP.
| |
Collapse
|
24
|
Friis LM, Pin C, Taylor DE, Pearson BM, Wells JM. A role for the tet(O) plasmid in maintaining Campylobacter plasticity. Plasmid 2006; 57:18-28. [PMID: 16934869 DOI: 10.1016/j.plasmid.2006.06.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2006] [Revised: 05/05/2006] [Accepted: 06/09/2006] [Indexed: 11/23/2022]
Abstract
Genomic sequencing projects are beginning to reveal regions of extensive DNA homology between bacterial genera. Public fears of the spread of genetically modified organisms into the food chain and the increasing prevalence of multi-drug resistant disease in humans highlight the implications of horizontal gene transfer. The striking DNA sequence similarity between the two uniquely identified tetracycline resistant (Tc(R)) Campylobacter plasmids, pCC31 and pTet, suggests their conserved acquisition and maintenance within Campylobacter [Batchelor, R.A., Pearson, B.M., Friis, L.M., Guerry, P., Wells, J.M. 2004. Nucleotide sequences and comparison of two large conjugative plasmids from different Campylobacter species. Microbiology 150, 3507-3517]. It is thus likely that these and other conjugative plasmids are highly prevalent and broadly distributed across several continents. Microarray technology is now enabling fast and extensive genomic comparisons to be made and allows us to investigate intra- and inter-genetic conservation and variability. This study details the development of a microarray specific for genes from Campylobacter plasmids pCC31, pTet and pVir and its application to the analysis of Campylobacter plasmid gene presence and preservation throughout environmental and clinical isolates. Application of the iterative algorithm GENCOM (freely available at ) is used as a rapid and effective way of comparing the content and conservation of plasmids in bacteria and provides details of the Campylobacter flexible gene pool and its contribution to genomic plasticity.
Collapse
Affiliation(s)
- L M Friis
- Institute of Food Research, Colney Lane, Norwich, Norfolk NR4 7UA, UK.
| | | | | | | | | |
Collapse
|
25
|
Friis LM, Pin C, Pearson BM, Wells JM. In vitro cell culture methods for investigating Campylobacter invasion mechanisms. J Microbiol Methods 2005; 61:145-60. [PMID: 15722140 DOI: 10.1016/j.mimet.2004.12.003] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2004] [Revised: 12/04/2004] [Accepted: 12/06/2004] [Indexed: 01/24/2023]
Abstract
Studying the mechanisms of Campylobacter pathogenesis is complicated by the lack of simple animal models that mimic the disease seen in humans. In vitro cell culture methods provide a useful alternative to investigate the interactions between Campylobacter and the host epithelium that occur during infection. In the genomics era there is an increasing use of in vitro cell culture techniques to interrogate the potential role of different genes in pathogenesis. The aim of this review was to discuss the suitability and limitations of the various experimental approaches that might be adopted. We review current knowledge concerning the influence of cell-specific as well as bacterial factors required for Campylobacter invasion such as flagella and secreted proteins. The involvement and effects of phase variation on the results of invasion studies in cell culture emphasise the need to verify observed strain variations. We present the use of a mathematical Invasion Success Model to analyse Campylobacter invasion and show that it can be used to derive three strain dependent characteristics Imax, k, and I0. Even by combining data from independent experiments the Invasion Success Model can be used to statistically compare Campylobacter strains for their invasion of epithelial cells. Recommendations are given for the adoption of standard assay parameters and analytical methods such as the Invasion Success Model in order to facilitate comparison of data generated in different laboratories.
Collapse
Affiliation(s)
- L M Friis
- Institute of Food Research, Colney Lane, Norwich, NR4 7UA, United Kingdom
| | | | | | | |
Collapse
|
26
|
Robinson K, Chamberlain LM, Lopez MC, Rush CM, Marcotte H, Le Page RWF, Wells JM. Mucosal and cellular immune responses elicited by recombinant Lactococcus lactis strains expressing tetanus toxin fragment C. Infect Immun 2004; 72:2753-61. [PMID: 15102785 PMCID: PMC387891 DOI: 10.1128/iai.72.5.2753-2761.2004] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2003] [Revised: 12/23/2003] [Accepted: 01/21/2004] [Indexed: 12/13/2022] Open
Abstract
The mucosal and cellular responses of mice were studied, following mucosal-route administration of recombinant Lactococcus lactis expressing tetanus toxin fragment C (TTFC), which is a known immunogen protective against tetanus. A TTFC-specific T-cell response with a mixed profile of T-helper (Th) subset-associated cytokines was elicited in the intestine, with a Th2 bias characteristic of a mucosal response. These results correlated with the humoral response, where equivalent titers of anti-TTFC immunoglobulin G1 (IgG1) and IgG2a in serum were accompanied by an elevated IgA-specific response at more than one mucosal site. The route of vaccination had an important role in determining the immune response phenotype, as evidenced by the fact that an IgG1-biased subclass profile was obtained when lactococci were administered parenterally. Stimulation of splenic or mesenteric lymph node cells with lactococci resulted in their proliferation and the secretion of gamma interferon via antigen-specific and innate immune mechanisms. The data therefore provide further evidence of the potential of recombinant lactococcal vaccines for inducing systemic and mucosal immune responses.
Collapse
Affiliation(s)
- K Robinson
- Department of Pathology, University of Cambridge, Cambridge CB2 1QP, United Kingdom.
| | | | | | | | | | | | | |
Collapse
|
27
|
Abstract
Whole genome DNA microarrays were constructed and used to investigate genomic diversity in 18 Campylobacter jejuni strains from diverse sources. New algorithms were developed that dynamically determine the boundary between the conserved and variable genes. Seven hypervariable plasticity regions (PR) were identified in the genome (PR1 to PR7) containing 136 genes (50%) of the variable gene pool. When comparisons were made with the sequenced strain NCTC11168, the number of absent or divergent genes ranged from 2.6% (40 genes) to 10.2% (163) and in total 16.3% (269) of the genes were variable. PR1 contains genes important in the utilisation of alternative electron acceptors for respiration and may confer a selective advantage to strains in restricted oxygen environments. PR2, 3 and 7 contain many outer membrane and periplasmic proteins and hypothetical proteins of unknown function that might be linked to phenotypic variation and adaptation to different ecological niches. PR4, 5 and 6 contain genes involved in the production and modification of antigenic surface structures.
Collapse
Affiliation(s)
- B M Pearson
- BBSRC Institute of Food Research, Norwich Research Park, Colney, Norwich NR4 7UA, UK
| | | | | | | | | | | |
Collapse
|
28
|
Wells JM. Potential applications of differential permeability membranes in the control of gas composition in closed circuit atmospheres. Life Support Biosph Sci 2002; 5:271-7. [PMID: 11876193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
Long hyperbaric exposures of humans, at pressures in excess of 2.5 atmospheres, require that the oxygen concentration of the breathing gas be maintained at levels less than atmospheric air, in order to prevent pulmonary oxygen toxicity. Carbon dioxide produced by humans must be removed from the breathing gas of closed environments. Differential permeability gas separation devices can be used to reduce the concentrations of carbon dioxide and oxygen in recirculating nitrogen/oxygen atmospheres. The application of these devices can eliminate the requirement for nitrogen to dilute oxygen, and reduce, or eliminate, the requirement for carbon dioxide absorbents. The use of differential permeability gas separation devices for the production of nitrogen/oxygen breathing gas mixtures for divers, using air as a source gas, can produce mixtures with unacceptably high levels of carbon dioxide.
Collapse
Affiliation(s)
- J M Wells
- Undersea Research Foundation, Box 696, North, VA, 23128, USA.
| |
Collapse
|
29
|
Affiliation(s)
- J M Wells
- Department of Chemistry, Purdue University, West Lafayette, IN 47907-1393, USA
| | | | | |
Collapse
|
30
|
Reid GE, Wu J, Chrisman PA, Wells JM, McLuckey SA. Charge-state-dependent sequence analysis of protonated ubiquitin ions via ion trap tandem mass spectrometry. Anal Chem 2001; 73:3274-81. [PMID: 11476225 DOI: 10.1021/ac0101095] [Citation(s) in RCA: 119] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
One of the major factors governing the "top-down" sequence analysis of intact multiply protonated proteins by tandem mass spectrometry is the effect of the precursor ion charge state on the formation of product ions. To more fully understand this effect, electrospray ionization coupled to a quadrupole ion trap mass spectrometer, collision-induced dissociation, and gas-phase ion/ion reactions have been employed to examine the fragmentation of the [M + 12H]12+ to [M + H]+ ions of bovine ubiquitin. At low charge states (+1 to +6), loss of NH3 or H2O from the protonated precursor and directed cleavage at aspartic acid residues was observed. At intermediate charge states, (+7, +8, and +9), extensive nonspecific fragmentation of the protein backbone was observed, with 50% sequence coverage obtained from the [M + 8H]8+ ion alone. At high charge states, (+10, +11, +12), the single dominant channel that was observed was the preferential fragmentation of a single proline residue. These data can be readily explained in terms of the current model for intramolecular proton mobilization, that is, the "mobile proton model", the mechanisms for amide bond dissociation developed for protonated peptides, as well as the structures of the multiply charged ions of ubiquitin in the gas phase, examined by ion mobility and hydrogen/deuterium exchange measurements.
Collapse
Affiliation(s)
- G E Reid
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907-1393, USA
| | | | | | | | | |
Collapse
|
31
|
Abstract
Electrochemical reduction of the iron bound in the heme group of cytochrome c is shown to occur in the nano-electrospray capillary if the protein is sprayed from neutral water using a steel wire as the electrical contact. Quadrupole ion trap collisional activation is used to study the dissociation reactions of cytochrome c as a function of the oxidation state of the iron. Oxidized (Fe(III)) cytochrome c dissociates via sequence-specific amide bond cleavage, while the reduced (Fe(II)) form of the protein dissociates almost exclusively by loss of protonated heme. Apo-cytochrome c, from which the heme has been removed either via gas-phase dissociation of the reduced holo-protein or via solution chemistry, dissociates via amide bond cleavage in similar fashion to the oxidized holo-protein.
Collapse
Affiliation(s)
- J M Wells
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907-1393, USA
| | | | | | | | | |
Collapse
|
32
|
Conn KJ, Ullman MD, Eisenhauer PB, Fine RE, Wells JM. Decreased expression of the NADH:ubiquinone oxidoreductase (complex I) subunit 4 in 1-methyl-4-phenylpyridinium -treated human neuroblastoma SH-SY5Y cells. Neurosci Lett 2001; 306:145-8. [PMID: 11406316 DOI: 10.1016/s0304-3940(01)01888-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Oxidative stress and mitochondrial dysfunction have been implicated in Parkinson's disease (PD) pathology. NADH:ubiquinone oxidoreductase (complex I) (EC 1.6.99.3) enzyme activity is aberrant in both PD and 1-methyl-4-phenylpyridinium (MPP(+)) models of PD. Reverse transcription polymerase chain reaction of RNA isolated from MPP(+)-treated human neuroblastoma SH-SY5Y cells identified changes in steady-state mRNA levels of the mitochondrial transcript for subunit 4 of complex I (ND4). Expression of ND4 decreased to nearly 50% after 72 h of MPP(+) (1 mM) exposure. The expression of other mitochondrial transcripts did not change significantly under the same conditions. Pre-incubation of cells with the free-radical spin-trap, N-tert-butyl-alpha-(2-sulfophenyl)-nitrone prior to MPP(+) exposure, prevented decreases in cell viability and ND4 expression. This suggests that functional defects in complex I enzyme activity in PD and MPP(+) toxicity may result from changes in steady-state mRNA levels and that free radicals may be important in this process.
Collapse
Affiliation(s)
- K J Conn
- Department of Veterans Affairs, VA Medical Center, 200 Springs Road, Bedford, MA 01730, USA.
| | | | | | | | | |
Collapse
|
33
|
Abstract
Aplasia cutis congenita describes localized defects of skin that may have many causes. A 6-month-old male presented with bilateral atrophic patches on his cheeks distributed along a line from the preauricular area to the angle of the mouth. They had been present since birth. He had no other abnormalities detectable on examination and no family history of similar lesions. A distinct collar of long pale hairs surrounded the lesions, especially the largest one. Histology showed changes consistent with aplasia cutis congenita or focal facial dermal dysplasia. We propose our patient's lesions may be the result of failure of ectodermal fusion over embryological closure lines. This may be a distinct subgroup of atrophic facial lesions.
Collapse
Affiliation(s)
- J M Wells
- Department of Dermatology, Royal Brisbane Hospital, Brisbane, Queensland, Australia.
| | | |
Collapse
|
34
|
Abstract
There have been many new and exciting developments in mass spectrometer systems in recent years. Many of these developments are being driven by challenges presented by molecular biology. The activity is fueled by resources being devoted to drug development, for example, and other medically and biologically related activities. Progress in these applications will be accelerated by improved sensitivity, specificity, and speed. In mass spectrometry, this translates to greater mass resolving power, mass accuracy, mass-to-charge range, efficiency, and speed. It is safe to say that the demands resulting from current analytical needs are likely to be met to varying degrees but probably not by a single analyzer technology or hybrid instrument. On-line and/or off-line separations and manipulations combined with mass spectrometry will also play increasingly important roles. For any analyzer, or combination of analyzers, to become widely used it must have an important application for which its figures of merit are best suited, relative to competing approaches. The relative cost of competing technologies is also an important factor. The mass filter has seen so much use in the past 30 years because its characteristics best fit a wide range of applications. As an example, biological applications, which are currently driving many instrument development activities in mass spectrometry, demand more information, of higher quality, from less material, faster, and at lower cost. Which technologies will dominate biological applications in the coming years is open to speculation. However, in considering the relative merits of today's dominant mass analyzers, areas of opportunity for improvement are apparent. Furthermore, new and more demanding measurement needs are constantly being recognized that will continue to exercise the creativity of the mass spectrometry community.
Collapse
Affiliation(s)
- S A McLuckey
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907-1393, USA.
| | | |
Collapse
|
35
|
Chrisman PA, Newton KA, Reid GE, Wells JM, McLuckey SA. Loss of charged versus neutral heme from gaseous holomyoglobin ions. Rapid Commun Mass Spectrom 2001; 15:2334-2340. [PMID: 11746900 DOI: 10.1002/rcm.512] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The dissociation of holomyoglobin ions ranging in charge state from +10 to +2 has been studied using collisional activation in a quadrupole ion trap. Collisional activation times and amplitudes were varied to investigate the effects of these variables on dissociation of the heme group from the holoprotein. The onset of neutral heme loss occurs at a lower activation amplitude than loss of charged heme. For solutions of ferri-myoglobin, charged heme loss was prominent for +10 to +4 holomyoglobin ions, while neutral heme loss product was found to be dominant for charge states +3 and +2. For any given charge state, activation of holomyoglobin ions from a solution containing primarily ferro-myoglobin yielded significantly more abundant neutral heme loss products than was observed for activation of ions from solutions containing primarily ferri-myoglobin. The relative concentrations of the two oxidation states were shown to be affected by redox chemistry within the nano-electrospray emitter used in this work. Results from a double activation experiment revealed that the precursor ions of a given charge state contained a mixture of two populations, with ferro-myoglobin giving rise to neutral heme loss upon dissociation and ferri-myoglobin yielding charged heme. No evidence for electron transfer upon collisional activation of ferri-myoglobin ions was observed. Furthermore, little or no evidence for electron transfer associated with ion/ion reactions with anions derived from perfluoro-1,3-dimethylcyclohexane was observed. Definitive results could not be drawn for the lowest precursor ion charge states (+3 and +2) due to low dissociation efficiencies.
Collapse
Affiliation(s)
- P A Chrisman
- 1393 Brown Laboratory, Department of Chemistry, Purdue University, West Lafayette, IN 47907, USA
| | | | | | | | | |
Collapse
|
36
|
Abstract
A 14-year-old boy presented with widespread cutaneous and mucosal lesions clinically consistent with erythema multiforme. He gave a history of previous episodes of a similar eruption. Histological examination of a representative lesion showed changes consistent with erythema multiforme. It also, however, contained large numbers of eosinophils, forming a dermal interstitial infiltrate and epidermal microabscesses. The full blood examination showed a persistent eosinophilia. The appearances initially confused two experienced dermatopathologists.
Collapse
Affiliation(s)
- J M Wells
- Royal Brisbane Hospital, Queensland, Australia.
| | | | | |
Collapse
|
37
|
Eisenhauer PB, Johnson RJ, Wells JM, Davies TA, Fine RE. Toxicity of various amyloid beta peptide species in cultured human blood-brain barrier endothelial cells: increased toxicity of dutch-type mutant. J Neurosci Res 2000; 60:804-10. [PMID: 10861793 DOI: 10.1002/1097-4547(20000615)60:6<804::aid-jnr13>3.0.co;2-1] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The amyloid beta peptide (A beta) is the major component of the neuritic and cerebrovascular amyloid plaques that are one of the characteristic features of Alzheimer's disease (AD). This peptide has been shown to be toxic to several relevant cell types, including neurons, cerebrovascular smooth muscle cells, and endothelial cells. We have studied the toxic effects of both soluble and aggregated species of A beta(1-40) and the mutation A beta(1-40)Glu-->Gln(22), which is the major species deposited in the cerebrovascular blood vessels of victims of hereditary cerebral hemorrhage with amyloidosis, Dutch type. We find that aggregates of both peptides, as well as of A beta(1-42) and A beta(25-35), are toxic to cultured human cerebrovascular endothelial cells (hBEC) obtained from the brain of a victim of AD (at doses lower than those that are toxic to CNS neurons or leptomeningeal smooth muscle cells). Soluble A beta(1-40) Gln(22) is equally toxic to hBEC, whereas wild-type A beta(1-40) is toxic only at higher doses. This toxicity is seen at the lowest dose of A beta(1-40) Gln (22) used, 20 nM. The soluble A beta(1-40)Gln(22) aggregates on the surface of the cells, in contrast to A beta(1-40), and its toxicity can be blocked both by an inhibitor of free radical formation and by Congo red, which inhibits amyloid fibril formation. We discuss the possibility that the enhanced toxicity of A beta(1-40)Gln(22) is mediated by a A beta receptor on the endothelial cells.
Collapse
|
38
|
Gilbert C, Robinson K, Le Page RW, Wells JM. Heterologous expression of an immunogenic pneumococcal type 3 capsular polysaccharide in Lactococcus lactis. Infect Immun 2000; 68:3251-60. [PMID: 10816470 PMCID: PMC97573 DOI: 10.1128/iai.68.6.3251-3260.2000] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In order to develop a new system for the analysis of capsular biosynthetic pathways we have explored the possibility of expressing type 3 capsular polysaccharide (CPS) from the pathogen Streptococcus pneumoniae in Lactococcus lactis, an unencapsulated lactic acid bacterium being developed as a vaccine delivery vehicle for mucosal immunization. Only three of the four type 3 CPS biosynthesis genes were found to be necessary for the abundant formation (120 mg liter(-1)) of an extracellular type 3 CPS in L. lactis, implying a role for the type 3-specific synthase in the extracellular transport of the CPS or implying the existence of an alternative export system in L. lactis. The authenticity of the expressed heterologous polysaccharide was established by chemical and immunological analyses. Proton and carbon nuclear magnetic resonance spectroscopy of CPSs purified from L. lactis and S. pneumoniae showed that the two CPS structures were identical. When mice were immunized intraperitoneally with 3.5 x 10(6) CFU of live recombinant lactococci expressing a total of approximately 0.5 microgram of type 3 CPS, the immune responses elicited appeared identical to those observed in mice inoculated with 0.5 microgram of type 3 CPS purified from S. pneumoniae. These findings show that L. lactis is a useful host in which to study the role and function of genes involved in the production of bacterial capsules. Additionally, L. lactis shows potential as a host for the safe production of capsule antigens and as a vaccine delivery vehicle for polysaccharide antigens.
Collapse
MESH Headings
- Animals
- Antibodies, Bacterial/blood
- Antigens, Bacterial/biosynthesis
- Antigens, Bacterial/chemistry
- Antigens, Bacterial/genetics
- Bacterial Vaccines/immunology
- Cloning, Molecular
- Gene Expression
- Injections, Intraperitoneal
- Lactococcus lactis/genetics
- Lactococcus lactis/immunology
- Mice
- Nuclear Magnetic Resonance, Biomolecular
- Polysaccharides, Bacterial/biosynthesis
- Polysaccharides, Bacterial/chemistry
- Polysaccharides, Bacterial/genetics
- Streptococcus pneumoniae/enzymology
- Streptococcus pneumoniae/genetics
- Streptococcus pneumoniae/immunology
- Vaccination
- Vaccines, Synthetic/immunology
Collapse
Affiliation(s)
- C Gilbert
- Cortecs Centre for Vaccine Discovery, Department of Pathology, University of Cambridge, Cambridge CB2 1QP, United Kingdom.
| | | | | | | |
Collapse
|
39
|
Caudales R, Wells JM, Butterfield JE. Cellular fatty acid composition of cyanobacteria assigned to subsection II, order Pleurocapsales. Int J Syst Evol Microbiol 2000; 50 Pt 3:1029-1034. [PMID: 10843042 DOI: 10.1099/00207713-50-3-1029] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The cellular fatty acid composition of five of the six genera of unicellular cyanobacteria in subsection II, Pleurocapsales (Dermocarpa, Xenococcus, Dermocarpella, Myxosarcina and the Pleurocapsa assemblage) contained high proportions of saturated straight-chain fatty acids (26-41% of the total) and unsaturated straight chains (40-67%). Isomers of 16:1 were the main monounsaturated acid component (11-59%). Polyunsaturated acids were present at trace levels (0-1% or less) in Xenococcus and Myxosarcina, at concentrations of less than 7% in Dermocarpa, Dermocarpella, Pleurocapsa and CCMP 1489, and at high concentrations (35% or more) in Chroococcidiopsis. Chroococcidiopsis was also different in terms of the percentage of 16:1 isomers (10-12%) compared to other genera (30-59%), and in terms of total 16-carbon and 18-carbon fatty acids. In general, the composition and heterogeneity of fatty acids in the order Pleurocapsales was similar to that reported for the unicellular cyanobacteria of subsection I, order Chroococcales.
Collapse
|
40
|
Abstract
Endoderm that forms the respiratory and digestive tracts is a sheet of approximately 500–1000 cells around the distal cup of an E7.5 mouse embryo. Within 2 days, endoderm folds into a primitive gut tube from which numerous organs will bud. To characterize the signals involved in the developmental specification of this early endoderm, we have employed an in vitro assay using germ layer explants and show that adjacent germ layers provide soluble, temporally specific signals that induce organ-specific gene expression in endoderm. Furthermore, we show that FGF4 expressed in primitive streak-mesoderm can induce the differentiation of endoderm in a concentration-dependent manner. We conclude that the differentiation of gastrulation-stage endoderm is directed by adjacent mesoderm and ectoderm, one of the earliest reported patterning events in formation of the vertebrate gut tube.
Collapse
Affiliation(s)
- J M Wells
- Department of Molecular and Cellular Biology, Howard Hughes Medical Institute, Harvard University, Cambridge, Massachusetts 02138, USA.
| | | |
Collapse
|
41
|
Abstract
Electroporation was applied to enhance gene transfer into subcutaneous MC2 murine breast tumors. Cultured MC2 cells were also transfected by electroporation or by cationic liposomes in the presence of serum using pSV-luc plasmids. Electroporation parameters and liposome formulation were optimized to achieve the highest relative levels of transfection. An electric field threshold for successful electrotransfection in cultured cells appeared around 800-900 V/cm. The liposomes used contained the cationic lipid dioleoyl-3-trimethylammonium propane (DOTAP). Multilamellar vesicles (MLV) had a 10-fold advantage over small unilamellar vesicles (SUV) in cell culture transfection. For in vivo gene delivery, the plasmids were injected either alone, or in complex with MLV or SUV DOTAP liposomes. A series of six electric pulses 1 ms long were applied across tumors, using caliper electrodes on the skin surface. Electric field strengths ranged from 400-2300 V/cm. Luciferase expression was approximately two orders of magnitude higher than controls in tumors treated with pulses > or =800 V/cm. Differences between enhanced relative levels of transfection using uncomplexed plasmid and lipoplexes were not statistically significant. Distribution of DNA into tumor tissues was monitored by fluorescence in situ PCR. The highest numbers of fluorescent cells were found in tumors electroporated following the injection of plasmid. The significant transfection improvement shows that in vivo electroporation is a powerful tool for local gene delivery to tumors.
Collapse
Affiliation(s)
- J M Wells
- Molecular and Cellular Biophysics Department, Roswell Park Cancer Institute, Buffalo, NY 14263-0001, USA
| | | | | | | | | |
Collapse
|
42
|
Abstract
Endoderm, one of the three principal germ layers, contributes to all organs of the alimentary tract. For simplicity, this review divides formation of endodermal organs into four fundamental steps: (a) formation of endoderm during gastrulation, (b) morphogenesis of a gut tube from a sheet of cells, (c) budding of organ domains from the tube, and (d) differentiation of organ-specific cell types within the growing buds. We discuss possible mechanisms that regulate how undifferentiated endoderm becomes specified into a myriad of cell types that populate the respiratory and gastrointestinal tracts.
Collapse
Affiliation(s)
- J M Wells
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
| | | |
Collapse
|
43
|
Abstract
The ability of homogenates from Alzheimer and control brains to inhibit formation of thiobarbituric acid reactive products (TBAR) induced by free radicals was compared. The assay for TBAR was modified by adding 1% sodium dodecyl sulfate (SDS) to prevent chromogen adsorption by biological matrices, and by extending the incubation time. The inhibitory activities required smaller equivalents of Alzheimer brain homogenates than control homogenates. Similar inhibitory activities were seen in homogenates from amygdala, temporal cortex and cerebellum. The inhibitory activities were similar in brain homogenates from individuals with different apolipoprotein E status. These results indicate that Alzheimer brain tissue has either increased content of free radical scavengers or is more sensitive to free radical attack than control brains.
Collapse
Affiliation(s)
- L Volicer
- E.N. Rogers Memorial Veterans Hospital, Geriatric Research Education Clinical Center, Bedford, MA 01730, USA.
| | | | | | | |
Collapse
|
44
|
Abstract
Dual-detector differential non-destructive Fourier transform detection in a quadrupole ion trap is shown to improve signal intensity and reduce noise compared with spectra recorded using a single detector. A larger area detector in each end-cap electrode is machined to fit its hyperbolic shape and so minimize field imperfections on the z-axis. Argon, acetophenone and bromobenzene spectra were recorded to allow a comparison between single- and dual-detector (differential) modes of detection and to demonstrate the improvement achieved with differential detection. Copyright 1999 John Wiley & Sons, Ltd.
Collapse
Affiliation(s)
- ER Badman
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907-1393, USA
| | | | | | | | | |
Collapse
|
45
|
Abstract
Enriched wash from healthy and decayed portions of 341 fruits and vegetables collected in the marketplace and affected by fungal rots were tested for suspected Salmonella appearing as black, hydrogen sulfide-positive colonies on Salmonella-Shigella agar incubated at 37°C. Suspected Salmonella occurred in 20.2% of healthy and in 26.4% of decayed portions, two-thirds of which were caused by Alternaria and Botrytis. In a similar analysis of 121 samples with mechanical injuries, in which two-thirds were gouges, cuts, and bruises, there were no significant differences in Salmonella incidence between injured and uninjured portions. Of 332 suspected Salmonella randomly isolated from healthy and decayed or injured portions, 17 (5.1%) were confirmed as Salmonella by physiological and serological testing. When tomato, potato, and onion tissues were inoculated with Salmonella typhimurium, populations of that bacterium increased by one to two logs over a 48-h incubation at room temperature. Coinoculation of tissues with S. typhimurium and Botrytis or Rhizopus, but not Alternaria or Geotrichum, caused a statistically significant increase in populations of Salmonella compared with the controls.
Collapse
Affiliation(s)
- J M Wells
- USDA, Agricultural Research Service, Eastern Regional Research Center, 600 E. Mermaid Lane, Wyndmoor, PA 19038
| | - J E Butterfield
- USDA, Agricultural Research Service, Eastern Regional Research Center, 600 E. Mermaid Lane, Wyndmoor, PA 19038
| |
Collapse
|
46
|
Wells JM. Future directions in the analysis of gene expression in Alzheimer disease. Alzheimer Dis Assoc Disord 1999; 13 Suppl 1:S78-81. [PMID: 10369524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
This review briefly explores future directions for gene expression research in Alzheimer disease (AD). Two complementary techniques, differential display and gene expression arrays, allow researchers to identify differentially expressed genes. These techniques promote a systematic examination of gene expression. In conjunction with a technique that allows the isolation of mRNA from individual cells, differential display and gene expression array technology can be used to examine AD-induced changes in gene expression patterns in individual cells. This area of research should elucidate information that will provide a greater understanding of the pathological processes in AD and aid in the development of therapeutic agents.
Collapse
Affiliation(s)
- J M Wells
- Geriatric Research Education and Clinical Center, Edith Nourse Rogers Memorial Veterans Hospital, Bedford, Massachusetts 01730, USA
| |
Collapse
|
47
|
Tetaud E, Hanau S, Wells JM, Le Page RW, Adams MJ, Arkison S, Barrett MP. 6-Phosphogluconate dehydrogenase from Lactococcus lactis: a role for arginine residues in binding substrate and coenzyme. Biochem J 1999; 338 ( Pt 1):55-60. [PMID: 9931298 PMCID: PMC1220024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
A gene encoding 6-phosphogluconate dehydrogenase (6-PGDH, EC 1.1.1. 44) was identified from the homofermentative lactic acid bacterium Lactococcus lactis, by complementation of Escherichia coli mutants. The cloned gene was then expressed to high levels in E. coli and the protein purified for kinetic analysis. The enzyme had a Km for 6-phosphogluconate of 15.4+/-1.4 microM and for NADP of 1.9+/-0.2 microM at pH 7.5. Sequence comparison of the L. lactis 6-PGDH with the corresponding enzyme derived from the pathogenic protozoan Trypanosoma brucei and sheep liver revealed the substrate-binding residues to be identical in all three species, although the three coenzyme-binding pockets differed slightly. A totally conserved arginine residue (Arg-447), believed to bind the 6-phosphate of substrate, was mutated to lysine, aspartate, alanine or tryptophan. In each case enzyme activity was lost, confirming an essential role for this residue on activity. A second arginine (Arg-34), believed to be critical in binding the 2'-phosphate of cofactor NADP+, was mutated to a tyrosine residue, as found in one atypical isoform of the enzyme in Bacillus subtilis. This alteration led to decrease in affinity for NADP+ of nearly three orders of magnitude. A second 6-PGDH gene has been identified from the genome of B. subtilis. This second isoform contains an arginine (Arg-34) in this position, suggesting that B. subtilis has two 6-PGDHs with different coenzyme specificities.
Collapse
Affiliation(s)
- E Tetaud
- Laboratoire de Biologie Moléculaire et Immunologie de Parasites Protozoaires, UPRESA-5016 CNRS, Université Bordeaux II, France
| | | | | | | | | | | | | |
Collapse
|
48
|
Wells JM, Harris MJ, Boddy L. Encounter with New Resources Causes Polarized Growth of the Cord-Forming Basidiomycete Phanerochaete velutina on Soil. Microb Ecol 1998; 36:372-382. [PMID: 9852516 DOI: 10.1007/s002489900123] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Abstract The development and physiology of cord-forming saprotrophic basidiomycetes, which form extensive and persistent mycelial networks in woodland ecosystems, can be conveniently studied on non-sterile soil in laboratory microcosms mimicking field conditions. Morphological responses of Phanerochaete velutina mycelial systems to resource encounters, and decay partitioning following encounters, varied according to whether simulated woody litter was unsterile or autoclaved and on whether encounter took place at the mycelial foraging front or behind the margin (simulating litter fall onto established systems in the field). Results show that encounter of discrete resources by P. velutina is rapidly communicated to the entire mycelial system; that resource capture takes high priority at the expense of continued system extension and decay-derived carbon reallocation; and that polarized growth toward newly encountered resources, previously considered to occur infrequently with this species, may be readily detected using image analysis techniques. Potential advantages of polarized development of P. velutina are discussed.
Collapse
Affiliation(s)
- JM Wells
- School of Pure and Applied Biology, University of Wales, Cardiff, PO Box 915, Cardiff CF1 3TL, UK
| | | | | |
Collapse
|
49
|
Abstract
OBJECTIVE There is reason to question whether hyperemia after pressure occlusion is caused solely by local ischemia. This study quantitatively compared the response to the two forms of occlusion on the finger. DESIGN Blood flow was measured by laser Doppler continuously before, during, and for 40 minutes after a 2-minute occlusion of flow at the finger dorsum and at the plantar surface of the finger tip (finger pulp), which has a much higher arteriolar density than the dorsum. Occlusion to the same low level was carried out either with a cuff at the base of the finger or by direct pressure of the laser Doppler probe head. Comparison experiments were performed with the probe head heated to 44 degrees C to elicit maximal local vasodilation. SETTING Outpatient clinic. PARTICIPANTS Eleven healthy volunteers. MAIN OUTCOME MEASURES Magnitude and duration of skin blood flow after occlusion. RESULTS Cuff occlusion at the base of the finger produced a typical, short-lived hyperemic response at both finger dorsum and finger pulp. The peak level at finger dorsum was 17.6 +/- 1.4mL/min/100g, approximately a twofold increase over the baseline flow level. The duration of the hyperemic response was 3.6 +/- 0.8 minutes. The baseline flow at the finger pulp was three times greater than at the finger dorsum, and peak flow after occlusion was also three times higher (44.3 +/- 2.6 mL/min/100g). The duration of hyperemia at finger pulp was 4.2 +/- 0.9 minutes. After pressure occlusion at the finger dorsum the hyperemic peak was higher (26.7 +/- 4.2 mL/min/100g; p < .05) and the duration of hyperemia was four times longer (16.9 +/- 2.3 minutes; p < .01) than after cuff occlusion. At the finger pulp, the pressure-induced hyperemic peak was also greater than the peak after cuff occlusion (56.3 +/- 1.7mL/min/100g; p < .05), with a longer duration than after cuff occlusion (11.1 +/- 1.1min; p < .01). Thermal stimulation significantly reduced the differences between cuff- and pressure-induced occlusion. There was a slow increase in flow over the 40-minute monitoring period. The maximal flow reached was approximately 100mL/min/100g at both finger dorsum and finger pulp. At both sites, however, the maximal flow level was attained more rapidly than the control condition without prior occlusion. CONCLUSIONS These results confirmed that the pressure-induced hyperemic response is greater and of longer duration than that produced by flow ischemia alone. Thermal stimulation essentially abolishes the differences, suggesting that there is a common mechanism of vasodilatation. The mechanistic differences between pressure-induced and ischemic hyperemia remain to be determined.
Collapse
Affiliation(s)
- M S Rendell
- The Creighton Diabetes Center, Omaha, NE 68131, USA
| | | |
Collapse
|
50
|
Holmes AR, Gilbert C, Wells JM, Jenkinson HF. Binding properties of Streptococcus gordonii SspA and SspB (antigen I/II family) polypeptides expressed on the cell surface of Lactococcus lactis MG1363. Infect Immun 1998; 66:4633-9. [PMID: 9746559 PMCID: PMC108570 DOI: 10.1128/iai.66.10.4633-4639.1998] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The oral bacterium Streptococcus gordonii expresses two cell wall-associated polypeptides, designated SspA (1,542 amino acid residues) and SspB (1,462 amino acid residues), that have 70% sequence identity. These polypeptides are members of the antigen I/II family of oral streptococcal adhesins and mediate the binding of streptococci to salivary glycoproteins, collagen, and other oral microorganisms such as Actinomyces naeslundii. To determine if SspA and SspB have differential binding properties, the coding sequences of the sspA and sspB genes were cloned into expression plasmid vector pTREX1-usp45LS to generate pTREX1-sspA and pTREX1-sspB, respectively, and the Ssp polypeptides were displayed on the cell surface of Lactococcus lactis MG1363. Lactococcal cells expressing similar levels of surface SspA or SspB polypeptide were then compared for their abilities to adhere to a range of antigen I/II polypeptide substrates. More than twice as many L. lactis cells expressing SspA bound to immobilized salivary agglutinin glycoprotein (SAG) as did L. lactis cells expressing SspB. In contrast, lactococci expressing SspB adhered twice as well as lactococci producing SspA to collagen type I and to Candida albicans. The binding of A. naeslundii to lactococci was only weakly enhanced by surface expression of Ssp polypeptides. L. lactis(pTREX1-sspB) cells bound in greater numbers to SAG than did Enterococcus faecalis JH2-2 cells expressing SspB from pAM401EB-5. The results suggest that SspA and SspB have markedly different binding affinities for their oral substrates and thus may function to promote site diversity in colonization by S. gordonii.
Collapse
Affiliation(s)
- A R Holmes
- Department of Oral Sciences and Orthodontics, University of Otago, Dunedin, New Zealand
| | | | | | | |
Collapse
|