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Jaumdally S, Tomasicchio M, Pooran A, Esmail A, Kotze A, Meier S, Wilson L, Oelofse S, van der Merwe C, Roomaney A, Davids M, Suliman T, Joseph R, Perumal T, Scott A, Shaw M, Preiser W, Williamson C, Goga A, Mayne E, Gray G, Moore P, Sigal A, Limberis J, Metcalfe J, Dheda K. Frequency, kinetics and determinants of viable SARS-CoV-2 in bioaerosols from ambulatory COVID-19 patients infected with the Beta, Delta or Omicron variants. Nat Commun 2024; 15:2003. [PMID: 38443359 PMCID: PMC10914788 DOI: 10.1038/s41467-024-45400-1] [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: 10/04/2023] [Accepted: 01/22/2024] [Indexed: 03/07/2024] Open
Abstract
Airborne transmission of SARS-CoV-2 aerosol remains contentious. Importantly, whether cough or breath-generated bioaerosols can harbor viable and replicating virus remains largely unclarified. We performed size-fractionated aerosol sampling (Andersen cascade impactor) and evaluated viral culturability in human cell lines (infectiousness), viral genetics, and host immunity in ambulatory participants with COVID-19. Sixty-one percent (27/44) and 50% (22/44) of participants emitted variant-specific culture-positive aerosols <10μm and <5μm, respectively, for up to 9 days after symptom onset. Aerosol culturability is significantly associated with lower neutralizing antibody titers, and suppression of transcriptomic pathways related to innate immunity and the humoral response. A nasopharyngeal Ct <17 rules-in ~40% of aerosol culture-positives and identifies those who are probably highly infectious. A parsimonious three transcript blood-based biosignature is highly predictive of infectious aerosol generation (PPV > 95%). There is considerable heterogeneity in potential infectiousness i.e., only 29% of participants were probably highly infectious (produced culture-positive aerosols <5μm at ~6 days after symptom onset). These data, which comprehensively confirm variant-specific culturable SARS-CoV-2 in aerosol, inform the targeting of transmission-related interventions and public health containment strategies emphasizing improved ventilation.
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Affiliation(s)
- S Jaumdally
- Division of Pulmonology, Department of Medicine, Centre for Lung Infection and Immunity, University of Cape Town Lung Institute, Cape Town, South Africa
- Centre for the Study of Antimicrobial Resistance, South African Medical Research Council, Cape Town, South Africa
| | - M Tomasicchio
- Division of Pulmonology, Department of Medicine, Centre for Lung Infection and Immunity, University of Cape Town Lung Institute, Cape Town, South Africa
- Centre for the Study of Antimicrobial Resistance, South African Medical Research Council, Cape Town, South Africa
| | - A Pooran
- Division of Pulmonology, Department of Medicine, Centre for Lung Infection and Immunity, University of Cape Town Lung Institute, Cape Town, South Africa
- Centre for the Study of Antimicrobial Resistance, South African Medical Research Council, Cape Town, South Africa
| | - A Esmail
- Division of Pulmonology, Department of Medicine, Centre for Lung Infection and Immunity, University of Cape Town Lung Institute, Cape Town, South Africa
- Centre for the Study of Antimicrobial Resistance, South African Medical Research Council, Cape Town, South Africa
| | - A Kotze
- Division of Pulmonology, Department of Medicine, Centre for Lung Infection and Immunity, University of Cape Town Lung Institute, Cape Town, South Africa
- Centre for the Study of Antimicrobial Resistance, South African Medical Research Council, Cape Town, South Africa
| | - S Meier
- Division of Pulmonology, Department of Medicine, Centre for Lung Infection and Immunity, University of Cape Town Lung Institute, Cape Town, South Africa
- Centre for the Study of Antimicrobial Resistance, South African Medical Research Council, Cape Town, South Africa
| | - L Wilson
- Division of Pulmonology, Department of Medicine, Centre for Lung Infection and Immunity, University of Cape Town Lung Institute, Cape Town, South Africa
- Centre for the Study of Antimicrobial Resistance, South African Medical Research Council, Cape Town, South Africa
| | - S Oelofse
- Division of Pulmonology, Department of Medicine, Centre for Lung Infection and Immunity, University of Cape Town Lung Institute, Cape Town, South Africa
- Centre for the Study of Antimicrobial Resistance, South African Medical Research Council, Cape Town, South Africa
| | - C van der Merwe
- Division of Pulmonology, Department of Medicine, Centre for Lung Infection and Immunity, University of Cape Town Lung Institute, Cape Town, South Africa
- Centre for the Study of Antimicrobial Resistance, South African Medical Research Council, Cape Town, South Africa
| | - A Roomaney
- Division of Pulmonology, Department of Medicine, Centre for Lung Infection and Immunity, University of Cape Town Lung Institute, Cape Town, South Africa
- Centre for the Study of Antimicrobial Resistance, South African Medical Research Council, Cape Town, South Africa
| | - M Davids
- Division of Pulmonology, Department of Medicine, Centre for Lung Infection and Immunity, University of Cape Town Lung Institute, Cape Town, South Africa
- Centre for the Study of Antimicrobial Resistance, South African Medical Research Council, Cape Town, South Africa
| | - T Suliman
- Department of Medical Biosciences, University of the Western Cape, Cape Town, South Africa
| | - R Joseph
- Division of Medical Virology, Wellcome Centre for Infectious Diseases in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - T Perumal
- Division of Pulmonology, Department of Medicine, Centre for Lung Infection and Immunity, University of Cape Town Lung Institute, Cape Town, South Africa
- Centre for the Study of Antimicrobial Resistance, South African Medical Research Council, Cape Town, South Africa
| | - A Scott
- Division of Pulmonology, Department of Medicine, Centre for Lung Infection and Immunity, University of Cape Town Lung Institute, Cape Town, South Africa
- Centre for the Study of Antimicrobial Resistance, South African Medical Research Council, Cape Town, South Africa
| | - M Shaw
- Department of Medical Biosciences, University of the Western Cape, Cape Town, South Africa
| | - W Preiser
- Division of Medical Virology, Faculty of Medicine and Health Sciences, University of Stellenbosch Tygerberg Campus; Medical Virology, National Health Laboratory Service Tygerberg, Parow, Cape Town, South Africa
| | - C Williamson
- Division of Medical Virology, Wellcome Centre for Infectious Diseases in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
- Centre for the AIDS Programme of Research in South Africa (CAPRISA), Durban, South Africa
- National Health Laboratory Service (NHLS), Cape Town, South Africa
| | - A Goga
- HIV and Other Infectious Diseases Research Unit, South African Medical Research Council, Pretoria, South Africa
- Department of Paediatrics and Child Health, University of Pretoria, Pretoria, South Africa
| | - E Mayne
- Department of Immunology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- National Health Laboratory Services, Johannesburg, South Africa
- Division of Immunology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - G Gray
- South African Medical Research Council, Cape Town, South Africa
| | - P Moore
- Centre for the AIDS Programme of Research in South Africa (CAPRISA), Durban, South Africa
- National Institute for Communicable Diseases of the National Health Laboratory Service, Johannesburg, South Africa
- SA MRC Antibody Immunity Research Unit, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - A Sigal
- Africa Health Research Institute, Durban, South Africa
- School of Laboratory Medicine and Medical Sciences, University of KwaZulu-Natal, Durban, South Africa
- Max Planck Institute for Infection Biology, Berlin, Germany
| | - J Limberis
- Division of Pulmonary and Critical Care Medicine, Zuckerberg San Francisco General Hospital and Trauma Centre, University of California, San Francisco, San Francisco, CA, USA
| | - J Metcalfe
- Division of Pulmonary and Critical Care Medicine, Zuckerberg San Francisco General Hospital and Trauma Centre, University of California, San Francisco, San Francisco, CA, USA
| | - K Dheda
- Division of Pulmonology, Department of Medicine, Centre for Lung Infection and Immunity, University of Cape Town Lung Institute, Cape Town, South Africa.
- Centre for the Study of Antimicrobial Resistance, South African Medical Research Council, Cape Town, South Africa.
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK.
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Murphy D, Hendrikx LJ, Williamson C, Baumann J. Longitudinal survey of UK veterans with pre-existing mental health difficulties: mental health during the COVID-19 pandemic. BMJ Mil Health 2023; 169:529-534. [PMID: 35078940 PMCID: PMC8804302 DOI: 10.1136/bmjmilitary-2021-002046] [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] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 01/08/2022] [Indexed: 11/28/2022]
Abstract
INTRODUCTION At the start of the COVID-19 pandemic, individuals with pre-existing mental health difficulties were thought to be vulnerable to mental health deterioration due to the emerging threat and the actions taken to control infection rates. Yet, there remained a paucity of research investigating changes in veteran well-being, a population facing higher rates of mental health difficulties compared with the general public. This longitudinal study aimed to investigate the mental health and well-being of UK veterans with pre-existing mental health difficulties at two time points during the COVID-19 pandemic. METHODS UK treatment-seeking veterans (N=121) completed an online survey administered towards the end of the first UK lockdown in June 2020 and 1 year later. Data were gathered on sociodemographic characteristics as well as psychometric measures of post-traumatic stress disorder (PTSD), common mental disorders (CMDs), anger difficulties and alcohol misuse. RESULTS The proportion of veterans meeting criteria of PTSD, anger and alcohol misuse remained similar across the two time points, while significantly fewer veterans met criteria for CMDs 1 year later. A notable proportion of the sample reported challenges in attending mental and physical health appointments, which was positively associated with not working and negatively associated with more COVID-19-related stressors. CONCLUSIONS These findings suggest that, to date, veterans with pre-existing mental health difficulties appear to demonstrate resilience as the COVID-19 pandemic progressed. However, as the pandemic continued, veterans faced significantly more COVID-19-related stressors, less social support, as well as difficulties attending health appointments.
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Affiliation(s)
- Dominic Murphy
- Department of Research, Combat Stress, Leatherhead, UK
- King's Centre for Military Health Research, King's College London, London, UK
| | - L J Hendrikx
- Department of Research, Combat Stress, Leatherhead, UK
| | - C Williamson
- Department of Research, Combat Stress, Leatherhead, UK
- King's Centre for Military Health Research, King's College London, London, UK
| | - J Baumann
- Department of Research, Combat Stress, Leatherhead, UK
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Perini L, Gostinčar C, Likar M, Frisvad JC, Kostanjšek R, Nicholes M, Williamson C, Anesio AM, Zalar P, Gunde-Cimerman N. Interactions of Fungi and Algae from the Greenland Ice Sheet. Microb Ecol 2022:10.1007/s00248-022-02033-5. [PMID: 35608637 DOI: 10.1007/s00248-022-02033-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 05/03/2022] [Indexed: 06/15/2023]
Abstract
Heavily pigmented glacier ice algae Ancylonema nordenskiöldii and Ancylonema alaskanum (Zygnematophyceae, Streptophyta) reduce the bare ice albedo of the Greenland Ice Sheet, amplifying melt from the largest cryospheric contributor to eustatic sea-level rise. Little information is available about glacier ice algae interactions with other microbial communities within the surface ice environment, including fungi, which may be important for sustaining algal bloom development. To address this substantial knowledge gap and investigate the nature of algal-fungal interactions, an ex situ co-cultivation experiment with two species of fungi, recently isolated from the surface of the Greenland Ice Sheet (here proposed new species Penicillium anthracinoglaciei Perini, Frisvad and Zalar, Mycobank (MB 835602), and Articulospora sp.), and the mixed microbial community dominated by glacier ice algae was performed. The utilization of the dark pigment purpurogallin carboxylic acid-6-O-β-D-glucopyranoside (C18H18O12) by the two fungi was also evaluated in a separate experiment. P. anthracinoglaciei was capable of utilizing and converting the pigment to purpurogallin carboxylic acid, possibly using the sugar moiety as a nutrient source. Furthermore, after 3 weeks of incubation in the presence of P. anthracinoglaciei, a significantly slower decline in the maximum quantum efficiency (Fv/Fm, inverse proxy of algal stress) in glacier ice algae, compared to other treatments, was evident, suggesting a positive relationship between these species. Articulospora sp. did uptake the glycosylated purpurogallin, but did not seem to be involved in its conversion to aglycone derivative. At the end of the incubation experiments and, in conjunction with increased algal mortality, we detected a substantially increasing presence of the zoosporic fungi Chytridiomycota suggesting an important role for them as decomposers or parasites of glacier ice algae.
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Affiliation(s)
- L Perini
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000, Ljubljana, Slovenia.
- Department of Environmental Science, Aarhus University, 4000, Roskilde, Denmark.
| | - C Gostinčar
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000, Ljubljana, Slovenia
- Lars Bolund Institute of Regenerative Medicine, BGI-Qingdao, Qingdao, 266555, China
| | - M Likar
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000, Ljubljana, Slovenia
| | - J C Frisvad
- Department of Biotechnology and Biomedicine, Fungal Chemodiversity, Technical University of Denmark, Søltofts Plads, Building 221, 2800, Kgs. Lyngby, Denmark
| | - R Kostanjšek
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000, Ljubljana, Slovenia
| | - M Nicholes
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, BS8 1SS, UK
| | - C Williamson
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol, BS8 1SS, UK
| | - A M Anesio
- Department of Environmental Science, Aarhus University, 4000, Roskilde, Denmark
| | - P Zalar
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000, Ljubljana, Slovenia
| | - N Gunde-Cimerman
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000, Ljubljana, Slovenia
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Murphy D, Williamson C, Baumann J, Busuttil W, Fear NT. Exploring the impact of COVID-19 and restrictions to daily living as a result of social distancing within veterans with pre-existing mental health difficulties. BMJ Mil Health 2022; 168:29-33. [PMID: 33243764 PMCID: PMC7692021 DOI: 10.1136/bmjmilitary-2020-001622] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 10/22/2020] [Accepted: 10/27/2020] [Indexed: 11/05/2022]
Abstract
INTRODUCTION Data are emerging showing the adverse consequences on mental health of the general public due to the COVID-19 pandemic. Little is known about the needs of veterans with pre-existing mental health difficulties during the COVID-19 pandemic. METHODS Data were collected through a cross-sectional online survey from a randomly selected sample (n=1092) of military veterans who have sought help for mental health difficulties from a veteran-specific UK-based charity. The response rate was 25.2% (n=275). Participants were asked to complete a range of standardised mental health outcomes (post-traumatic stress disorder (PTSD): Post-traumatic Stress Disorder Checklist, common mental health difficulties (CMDs): 12-Item General Health Questionnaire, difficulties with anger: 5-Item Dimensions of Anger Reactions-Revised and alcohol misuse: Alcohol Use Disorders Identification Test) and endorse a list of potential stressors related to changes to daily life resulting from COVID-19. Regression analyses were fitted to explore predictors of mental health severity. RESULTS It was observed that symptoms of common mental disorder and PTSD (69.3% and 65.0%, respectively) were the most commonly reported to have been exacerbated by the pandemic. Lack of social support and reporting increasing numbers of stressors related to COVID-19 were consistently associated with increasing severity of a range of mental health difficulties. CONCLUSIONS Our findings suggest veterans who had pre-existing mental health difficulties prior to the outbreak of COVID-19 may be at increased risk of experiencing CMDs as a result of the pandemic. Intervening to improve levels of social support and offering practical guidance to better manage any additional stressors relating to the pandemic may provide strategies to help reduce the burden of mental health symptoms.
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Affiliation(s)
- Dominic Murphy
- The Research Department, Combat Stress, Leatherhead, UK
- King's Centre for Military Health Research (KCMHR), King's College London, Strand Campus, London, UK
| | - C Williamson
- The Research Department, Combat Stress, Leatherhead, UK
| | - J Baumann
- The Research Department, Combat Stress, Leatherhead, UK
| | - W Busuttil
- The Research Department, Combat Stress, Leatherhead, UK
| | - N T Fear
- King's Centre for Military Health, King's College London, London, UK
- Academic Centre for Defence Mental Health, Ministry of Defence, London, UK
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Chivers SC, Vasavan T, Nandi M, Hayes-Gill BR, Jayawardane IA, Simpson JM, Williamson C, Fifer WP, Lucchini M. Measurement of the cardiac time intervals of the fetal ECG utilising a computerised algorithm: A retrospective observational study. JRSM Cardiovasc Dis 2022; 11:20480040221096209. [PMID: 35574238 PMCID: PMC9102181 DOI: 10.1177/20480040221096209] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Revised: 04/04/2022] [Accepted: 04/05/2022] [Indexed: 11/16/2022] Open
Abstract
Objective Establish whether the reliable measurement of cardiac time intervals of the fetal ECG can be automated and to address whether this approach could be used to investigate large datasets. Design Retrospective observational study. Setting Teaching hospitals in London UK, Nottingham UK and New York USA. Participants Singleton pregnancies with no known fetal abnormality. Methods Archived fetal ECG's performed using the MonicaAN24 monitor. A single ECG (PQRST) complex was generated from 5000 signal-averaged beats and electrical cardiac time intervals measured in an automated way and manually. Main Outcome measure Validation of a newly developed algorithm to measure the cardiac time intervals of the fetal ECG. Results 188/236 (79.7%) subjects with fECGs of suitable signal:noise ratio were included for analysis comparing manual with automated measurement. PR interval was measured in 173/188 (92%), QRS complex in 170/188 (90%) and QT interval in 123/188 (65.4%). PR interval was 107.6 (12.07) ms [mean(SD)] manual vs 109.11 (14.7) ms algorithm. QRS duration was 54.72(6.35) ms manual vs 58.34(5.73) ms algorithm. QT-interval was 268.93 (21.59) ms manual vs 261.63 (36.16) ms algorithm. QTc was 407.5(32.71) ms manual vs 396.4 (54.78) ms algorithm. The QRS-duration increased with gestational age in both manual and algorithm measurements. Conclusion Accurate measurement of fetal ECG cardiac time intervals can be automated with potential application to interpretation of larger datasets.
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Affiliation(s)
- SC Chivers
- Department of Women and Children’s Health, King’s College London, London, UK
- Department of Fetal cardiology, Evelina London Children’s Hospital, London, UK
| | - T Vasavan
- Department of Women and Children’s Health, King’s College London, London, UK
| | - M Nandi
- School of Cancer and Pharmaceutical Sciences, King’s College London, London, UK
| | - BR Hayes-Gill
- Faculty of Engineering, University of Nottingham, Nottingham, UK
| | - IA Jayawardane
- Faculty of Engineering, University of Nottingham, Nottingham, UK
| | - JM Simpson
- Department of Fetal cardiology, Evelina London Children’s Hospital, London, UK
| | - C Williamson
- Department of Women and Children’s Health, King’s College London, London, UK
| | - WP Fifer
- Department of Pediatrics, Columbia University Medical Center, Morgan Stanley Children’s Hospital, New York, USA
- Department of Psychiatry, Columbia University, New York, USA
| | - M Lucchini
- Department of Pediatrics, Columbia University Medical Center, Morgan Stanley Children’s Hospital, New York, USA
- Department of Psychiatry, Columbia University, New York, USA
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Ovadia C, Nana M, Williamson C. Maternal medicine: calling for improved research quality. BJOG 2021; 129:378. [PMID: 34651410 DOI: 10.1111/1471-0528.16965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Accepted: 10/07/2021] [Indexed: 11/29/2022]
Affiliation(s)
- C Ovadia
- Department of Women and Children's Health, King's College London, London, UK
| | - M Nana
- Department of Women and Children's Health, King's College London, London, UK
| | - C Williamson
- Department of Women and Children's Health, King's College London, London, UK
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Williamson C, Brennan C. 717 The Introduction of a Discharge Letter Proforma For Hip Fracture Patients Improves Compliance with VTE Prophylaxis Prescription on Discharge: A Closed Loop Audit. Br J Surg 2021. [DOI: 10.1093/bjs/znab134.478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
Introduction
Venous thromboembolism (VTE) is a significant cause of morbidity and mortality in inpatients; with those undergoing lower limb surgery at particularly high risk. NICE recommends that Low Molecular Weight Heparin (LMWH) or Fondaparinux should be used for VTE prophylaxis for one month following hip fracture. Our local policy is to prescribe Dalteparin for 30 days following surgery.
Method
A closed loop audit of VTE prophylaxis on discharge for 193 patients with hip fractures was performed. The first audit cycle established whether VTE prophylaxis was being prescribed in line with departmental policy. Following this, a template discharge letter was introduced which included a prompt for appropriate prescription of VTE prophylaxis.
Results
Initially, data for 93 consecutive patients was collected. It was found that 13% had not received VTE prophylaxis in line with guidelines. Of these, six patients had no documented contraindication or alternative prophylaxis prescribed. Results were disseminated locally.
After introduction of the template discharge letter, data for 100 consecutive patients was collected. Re-audit showed a marked improvement in adherence to local policy with 95% of patients now receiving appropriate VTE prophylaxis on discharge.
Conclusions
Introduction of a template discharge letter prompts the documentation of contraindications to prophylaxis and improves compliance with local policy.
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Affiliation(s)
- C Williamson
- Royal Infirmary Edinburgh, Edinburgh, United Kingdom
| | - C Brennan
- Royal Infirmary Edinburgh, Edinburgh, United Kingdom
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Mitchell AL, Ovadia C, Syngelaki A, Souretis K, Martineau M, Girling J, Vasavan T, Fan HM, Seed PT, Chambers J, Walters J, Nicolaides K, Williamson C. Re-evaluating diagnostic thresholds for intrahepatic cholestasis of pregnancy: case-control and cohort study. BJOG 2021; 128:1635-1644. [PMID: 33586324 DOI: 10.1111/1471-0528.16669] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/12/2021] [Indexed: 12/27/2022]
Abstract
OBJECTIVE To determine the optimal total serum bile acid (TSBA) threshold and sampling time for accurate intrahepatic cholestasis of pregnancy (ICP) diagnosis. DESIGN Case-control, retrospective cohort studies. SETTING Antenatal clinics, clinical research facilities. POPULATION Women with ICP or uncomplicated pregnancies. METHODS Serial TSBA measurements were performed pre-/postprandially in 42 women with ICP or uncomplicated pregnancy. Third-trimester non-fasting TSBA reference ranges were calculated from 561 women of black, south Asian and white ethnicity. Rates of adverse perinatal outcomes for women with ICP but peak non-fasting TSBA below the upper reference range limit were compared with those in healthy populations. MAIN OUTCOME MEASURES Sensitivity and specificity of common TSBA thresholds for ICP diagnosis, using fasting and postprandial TSBA. Calculation of normal reference ranges of non-fasting TSBA. RESULTS Concentrations of TSBA increased markedly postprandially in all groups, with overlap between healthy pregnancy and mild ICP (TSBA <40 μmol/l). The specificity of ICP diagnosis was higher when fasting, but corresponded to <30% sensitivity for diagnosis of mild disease. Using TSBA ≥40 μmol/l to define severe ICP, fasting measurements identified 9% (1/11), whereas non-fasting measurements detected over 91% with severe ICP. The highest upper limit of the non-fasting TSBA reference range was 18.3 µmol/l (95% confidence interval: 15.0-35.6 μmol/l). A re-evaluation of published ICP meta-analysis data demonstrated no increase in spontaneous preterm birth or stillbirth in women with TSBA <19 µmol/l. CONCLUSIONS Postprandial TSBA levels are required to identify high-risk ICP pregnancies (TSBA ≥40 μmol/l). The postprandial rise in TSBA in normal pregnancy indicates that a non-fasting threshold of ≥19 µmol/l would improve diagnostic accuracy. TWEETABLE ABSTRACT Non-fasting bile acids improve the diagnostic accuracy of intrahepatic cholestasis of pregnancy diagnosis.
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Affiliation(s)
- A L Mitchell
- Department of Women and Children's Health, King's College London, Guy's Campus, London, UK
| | - C Ovadia
- Department of Women and Children's Health, King's College London, Guy's Campus, London, UK
| | - A Syngelaki
- Harris Birthright Research Centre for Fetal Medicine, Fetal Medicine Research Institute, King's College Hospital, London, UK
| | - K Souretis
- Harris Birthright Research Centre for Fetal Medicine, Fetal Medicine Research Institute, King's College Hospital, London, UK
| | - M Martineau
- Department of Metabolism, Digestion and Reproduction, Imperial College London, Hammersmith Campus, London, UK
| | - J Girling
- Obstetrics and Gynaecology Department, West Middlesex University Hospital, Middlesex, UK
| | - T Vasavan
- Department of Women and Children's Health, King's College London, Guy's Campus, London, UK
| | - H M Fan
- Department of Women and Children's Health, King's College London, Guy's Campus, London, UK
| | - P T Seed
- Department of Women and Children's Health, King's College London, St Thomas' Campus, London, UK
| | - J Chambers
- Women's Health Research Centre, Imperial College London, London, UK
| | - Jrf Walters
- Department of Metabolism, Digestion and Reproduction, Imperial College London, Hammersmith Campus, London, UK
| | - K Nicolaides
- Harris Birthright Research Centre for Fetal Medicine, Fetal Medicine Research Institute, King's College Hospital, London, UK
| | - C Williamson
- Department of Women and Children's Health, King's College London, Guy's Campus, London, UK
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Fleminger J, Seed PT, Smith A, Juszczak E, Dixon PH, Chambers J, Dorling J, Williamson C, Thornton JG, Chappell LC. Ursodeoxycholic acid in intrahepatic cholestasis of pregnancy: a secondary analysis of the PITCHES trial. BJOG 2020; 128:1066-1075. [PMID: 33063439 PMCID: PMC8246759 DOI: 10.1111/1471-0528.16567] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/08/2020] [Indexed: 12/13/2022]
Abstract
OBJECTIVE To evaluate whether a particular group of women with intrahepatic cholestasis of pregnancy (ICP), based on their presenting characteristics, would benefit from treatment with ursodeoxycholic acid (UDCA). DESIGN Secondary analysis of the PITCHES trial (ISRCTN91918806). SETTING United Kingdom. POPULATION OR SAMPLE 527 women with ICP. METHODS Subgroup analyses were performed to determine whether baseline bile acid concentrations or baseline itch scores moderated a woman's response to treatment with UDCA. MAIN OUTCOME MEASURES Bile acid concentration and itch score. RESULTS In women with baseline bile acid concentrations less than 40 μmol/l, treatment with UDCA resulted in increased post-randomisation bile acid concentrations (geometric mean ratio 1.19, 95% CI 1.00-1.41, P = 0.048). A test of interaction showed no significance (P = 0.647). A small, clinically insignificant difference was seen in itch response in women with a high baseline itch score (-6.0 mm, 95% CI -11.80 to -0.21, P = 0.042), with a test of interaction not showing significance (P = 0.640). Further subgroup analyses showed no significance. Across all women there was a weak relationship between bile acid concentrations and itch severity. CONCLUSIONS There was no subgroup of women with ICP in whom a beneficial effect of treatment with UDCA on bile acid concentration or itch score could be identified. This confirms that its routine use in women with this condition for improvement of bile acid concentration or itch score should be reconsidered. TWEETABLE ABSTRACT PITCHES: No group of women with ICP has been found in whom UDCA reduces bile acid concentrations or pruritus.
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Affiliation(s)
- J Fleminger
- Department of Women and Children's Health, School of Life Course Sciences, King's College London, London, UK
| | - P T Seed
- Department of Women and Children's Health, School of Life Course Sciences, King's College London, London, UK
| | - A Smith
- National Perinatal Epidemiology Unit Clinical Trials Unit, Nuffield Department of Population Health, University of Oxford, Oxford, UK
| | - E Juszczak
- National Perinatal Epidemiology Unit Clinical Trials Unit, Nuffield Department of Population Health, University of Oxford, Oxford, UK
| | - P H Dixon
- Department of Women and Children's Health, School of Life Course Sciences, King's College London, London, UK
| | | | - J Dorling
- Division of Neonatal-Perinatal Medicine, IWK Health Centre, Halifax, NS, Canada
| | - C Williamson
- Department of Women and Children's Health, School of Life Course Sciences, King's College London, London, UK
| | - J G Thornton
- Division of Child Health, Obstetrics and Gynaecology, University of Nottingham, Nottingham, UK
| | - L C Chappell
- Department of Women and Children's Health, School of Life Course Sciences, King's College London, London, UK
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10
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Cauldwell M, Mackie FL, Steer PJ, Henehghan MA, Baalman JH, Brennand J, Johnston T, Dockree S, Hedley C, Jarvis S, Khan S, McAuliffe FM, Mackillop L, Penna L, Smith B, Trivedi P, Verma S, Westbrook R, Winifield S, Williamson C. Pregnancy outcomes in women with primary biliary cholangitis and primary sclerosing cholangitis: a retrospective cohort study. BJOG 2020; 127:876-884. [DOI: 10.1111/1471-0528.16119] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/20/2020] [Indexed: 12/17/2022]
Affiliation(s)
- M Cauldwell
- Academic Department of Obstetrics and Gynaecology Chelsea and Westminster Hospital London UK
| | - FL Mackie
- Academic Department of Obstetrics and Gynaecology Birmingham Women’s and Children’s NHS Foundation Trust Birmingham UK
| | - PJ Steer
- Academic Department of Obstetrics and Gynaecology Chelsea and Westminster Hospital London UK
| | | | - JH Baalman
- UCD Perinatal Research Centre School of Medicine University College Dublin National Maternity Hospital Dublin Ireland
| | - J Brennand
- Department of Obstetrics Queen Elizabeth Hospital Glasgow Glasgow UK
| | - T Johnston
- Academic Department of Obstetrics and Gynaecology Birmingham Women’s and Children’s NHS Foundation Trust Birmingham UK
| | - S Dockree
- Women’s Centre Oxford University Hospitals NHS Foundation Trust Oxford UK
| | - C Hedley
- Department of Obstetrics King’s College Hospital London UK
| | - S Jarvis
- Department of Obstetrics Queen Charlotte’s and Chelsea Hospital London UK
| | - S Khan
- Liver Unit Queen Elizabeth Hospital Birmingham UK
| | - FM McAuliffe
- UCD Perinatal Research Centre School of Medicine University College Dublin National Maternity Hospital Dublin Ireland
| | - L Mackillop
- Women’s Centre Oxford University Hospitals NHS Foundation Trust Oxford UK
| | - L Penna
- Department of Obstetrics King’s College Hospital London UK
| | - B Smith
- Department of Hepatology Hammersmith Hospital London UK
| | - P Trivedi
- Liver Unit Queen Elizabeth Hospital Birmingham UK
| | - S Verma
- Department of Clinical and Experimental Medicine Brighton and Sussex Medical School Brighton UK
- Department of Gastroenterology and Hepatology Brighton and Sussex University Hospitals Brighton UK
| | - R Westbrook
- Department of Hepatology Royal Free Hospital London UK
| | - S Winifield
- Department of Obstetrics Leeds Teaching Hospitals Leeds UK
| | - C Williamson
- Department of Women and Children’s Health King’s College London London UK
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11
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Aquilante CL, Kao DP, Trinkley KE, Lin CT, Crooks KR, Hearst EC, Hess SJ, Kudron EL, Lee YM, Liko I, Lowery J, Mathias RA, Monte AA, Rafaels N, Rioth MJ, Roberts ER, Taylor MR, Williamson C, Barnes KC. Clinical implementation of pharmacogenomics via a health system-wide research biobank: the University of Colorado experience. Pharmacogenomics 2020; 21:375-386. [PMID: 32077359 PMCID: PMC7226704 DOI: 10.2217/pgs-2020-0007] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
In recent years, the genomics community has witnessed the growth of large research biobanks, which collect DNA samples for research purposes. Depending on how and where the samples are genotyped, biobanks also offer the potential opportunity to return actionable genomic results to the clinical setting. We developed a preemptive clinical pharmacogenomic implementation initiative via a health system-wide research biobank at the University of Colorado. Here, we describe how preemptive return of clinical pharmacogenomic results via a research biobank is feasible, particularly when coupled with strong institutional support to maximize the impact and efficiency of biobank resources, a multidisciplinary implementation team, automated clinical decision support tools, and proactive strategies to engage stakeholders early in the clinical decision support tool development process.
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Affiliation(s)
- Christina L Aquilante
- Colorado Center for Personalized Medicine, University of Colorado School of Medicine, Aurora, CO 80045, USA.,Department of Pharmaceutical Sciences, University of Colorado Skaggs School of Pharmacy & Pharmaceutical Sciences, Aurora, CO 80045, USA
| | - David P Kao
- Colorado Center for Personalized Medicine, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Katy E Trinkley
- Colorado Center for Personalized Medicine, University of Colorado School of Medicine, Aurora, CO 80045, USA.,Department of Clinical Pharmacy, University of Colorado Skaggs School of Pharmacy & Pharmaceutical Sciences, Aurora, CO 80045, USA
| | - Chen-Tan Lin
- Colorado Center for Personalized Medicine, University of Colorado School of Medicine, Aurora, CO 80045, USA.,University of Colorado Health, Aurora, CO 80045, USA
| | - Kristy R Crooks
- Colorado Center for Personalized Medicine, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | | | - Steven J Hess
- University of Colorado Health, Aurora, CO 80045, USA
| | - Elizabeth L Kudron
- Colorado Center for Personalized Medicine, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Yee Ming Lee
- Colorado Center for Personalized Medicine, University of Colorado School of Medicine, Aurora, CO 80045, USA.,Department of Clinical Pharmacy, University of Colorado Skaggs School of Pharmacy & Pharmaceutical Sciences, Aurora, CO 80045, USA
| | - Ina Liko
- Colorado Center for Personalized Medicine, University of Colorado School of Medicine, Aurora, CO 80045, USA.,Department of Pharmaceutical Sciences, University of Colorado Skaggs School of Pharmacy & Pharmaceutical Sciences, Aurora, CO 80045, USA
| | - Jan Lowery
- Colorado Center for Personalized Medicine, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Rasika A Mathias
- Colorado Center for Personalized Medicine, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Andrew A Monte
- Colorado Center for Personalized Medicine, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Nicholas Rafaels
- Colorado Center for Personalized Medicine, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Matthew J Rioth
- Colorado Center for Personalized Medicine, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Emily R Roberts
- Colorado Center for Personalized Medicine, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Matthew Rg Taylor
- Colorado Center for Personalized Medicine, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | | | - Kathleen C Barnes
- Colorado Center for Personalized Medicine, University of Colorado School of Medicine, Aurora, CO 80045, USA
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12
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Templeton DJ, Williamson C, Jin F, Hillman RJ, Roberts JM, Law C, Fairley CK, Garland SM, Grulich AE, Poynten IM. Prevalence and associations of larger burden of intra-anal high-grade squamous intraepithelial lesions at baseline in an Australian cohort of gay and bisexual men: The Study of the Prevention of Anal Cancer. Cancer Epidemiol 2020; 64:101661. [PMID: 31918181 DOI: 10.1016/j.canep.2019.101661] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2019] [Revised: 12/12/2019] [Accepted: 12/14/2019] [Indexed: 10/25/2022]
Abstract
OBJECTIVES To investigate factors associated with larger burden of intra-anal high-grade squamous intraepithelial lesions (HSIL) in a natural history study of HSIL. METHODS 617 gay and bisexual men (GBM) attended a baseline visit. High-resolution anoscopy-directed biopsy was performed of suspected HSIL. GBM with biopsy-confirmed HSIL (bHSIL) affecting a single-octant were compared with those who had bHSIL affecting a larger area. RESULTS Of 196 men with bHSIL at baseline, 73 (37.2 %) had larger bHSIL burden. Larger burden was independently associated with anal HPV16 detection (aOR 2.06, 95 % CI 1.09-3.89, p = 0.026) and infection with a greater number of high-risk HPV types (aOR per type increase 1.25, 95 % CI 1.05-1.49, p-trend = 0.010). CONCLUSION The observation that men with a larger burden of HSIL also had more risk factors for anal cancer suggests this group may warrant closer observation to ensure earlier detection, and thus improved prognosis, of individuals whose HSIL may progress to anal cancer.
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Affiliation(s)
- D J Templeton
- The Kirby Institute, Wallace Wurth Building, UNSW Sydney, Randwick, New South Wales 2031, Australia; Department of Sexual Health Medicine, Sydney Local Heath District, 16 Marsden Street, Camperdown, Sydney, New South Wales 2050, Australia; Sydney Medical School, The University of Sydney, Sydney, New South Wales 2006, Australia.
| | - C Williamson
- Department of Sexual Health Medicine, Sydney Local Heath District, 16 Marsden Street, Camperdown, Sydney, New South Wales 2050, Australia; Sydney Medical School, The University of Sydney, Sydney, New South Wales 2006, Australia; The University of Aberdeen, School of Medicine and Dentristy, Polwarth Building, Foresterhill, Aberdeen AB25 2ZD, UK.
| | - F Jin
- The Kirby Institute, Wallace Wurth Building, UNSW Sydney, Randwick, New South Wales 2031, Australia.
| | - R J Hillman
- St Vincent's Hospital, 390 Victoria Street, Darlinghurst, Sydney, New South Wales 2010, Australia.
| | - J M Roberts
- Douglass Hanly Moir Pathology, 14 Giffnock Avenue, Macquarie Park, Sydney, New South Wales 2113, Australia.
| | - C Law
- St Vincent's Hospital, 390 Victoria Street, Darlinghurst, Sydney, New South Wales 2010, Australia.
| | - C K Fairley
- Melbourne Sexual Health Centre, 580 Swanston Street, Carlton, Victoria 3053, Australia.
| | - S M Garland
- Department of Microbiology and Infectious Diseases, Royal Women's Hospital, 20 Flemington Road, Parkville, Victoria 3052, Australia; Department of Microbiology, Royal Children's Hospital, 50 Flemington Road, Parkville, Victoria 3052, Australia; Infection Immunity, Murdoch Children's Research Institute, Flemington Road, Parkville, Victoria 3052, Australia; Department of Obstetrics and Gynaecology, University of Melbourne, Grattan Street, Parkville, New South Wales 3052, Australia.
| | - A E Grulich
- The Kirby Institute, Wallace Wurth Building, UNSW Sydney, Randwick, New South Wales 2031, Australia.
| | - I M Poynten
- The Kirby Institute, Wallace Wurth Building, UNSW Sydney, Randwick, New South Wales 2031, Australia.
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13
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Shipe M, Maiga A, Deppen S, Welty V, Blume J, Aldrich M, Montgomery C, Dickerson A, Crockett J, Vaszar L, Williamson C, Regis S, Mckee B, Isbell J, Rickman O, Pinkerman R, Lambright E, Nesbitt J, Massion P, Grogan E. EP1.11-24 The TREAT Model 2.0: Predicting Lung Cancer in Patients Seeking Care in High-Risk Clinics. J Thorac Oncol 2019. [DOI: 10.1016/j.jtho.2019.08.2245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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14
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Manna LB, Ovadia C, Lövgren-Sandblom A, Chambers J, Begum S, Seed P, Walker I, Chappell LC, Marschall HU, Williamson C. Enzymatic quantification of total serum bile acids as a monitoring strategy for women with intrahepatic cholestasis of pregnancy receiving ursodeoxycholic acid treatment: a cohort study. BJOG 2019; 126:1633-1640. [PMID: 31483939 PMCID: PMC6899621 DOI: 10.1111/1471-0528.15926] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/09/2019] [Indexed: 12/18/2022]
Abstract
OBJECTIVE To evaluate enzymatic total serum bile acid quantification as a monitoring strategy for women with intrahepatic cholestasis of pregnancy (ICP) treated with ursodeoxycholic acid (UDCA). DESIGN Cohort. SETTING One UK university hospital. POPULATION 29 ICP cases treated with UDCA. METHODS Serial samples were collected prospectively throughout gestation. Total serum bile acids were measured enzymatically and individual bile acids by high-performance liquid chromatography-tandem mass spectrometry. Data were log-transformed and analysed with random effects generalised least square regression. MAIN OUTCOME MEASURES The relationship between enzymatic total bile acid measurements and individual bile acid concentrations after UDCA treatment. RESULTS In untreated women, cholic acid was the principal bile acid (51%) and UDCA concentrations were <0.5%, whereas UDCA constituted 60% (IQR 43-69) of serum bile acids following treatment and cholic acid fell to <20%. Changes in the total bile acid measurement reflected similar alterations in the concentrations of the pathologically elevated bile acids, e.g. a two-fold increase in enzymatic total bile acids is accompanied by approximately a two-fold increase in cholic acid and chenodeoxycholic acid at most UDCA doses (P < 0.001). Most of the effects of UDCA on cholic acid occur in the first week of treatment (60% relative reduction, P = 0.025, 95% CI 0.2-0.9, from 10 micromol/l (4.7-17.6) to 3.5 micromol/l (1.4-7.5). CONCLUSION Ursodeoxycholic acid becomes the main component of the bile acid measurement after treatment. Enzymatic total bile acid assays are good predictors of both cholic acid and chenodeoxycholic acid, the primary bile acids that are raised prior to treatment. TWEETABLE ABSTRACT Ursodeoxycholic acid constitutes approximately 60% of the bile acid measurement and reduces pathological cholic acid in treated women.
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Affiliation(s)
- L B Manna
- Division of Women and Children's Health, King's College London, London, UK
| | - C Ovadia
- Division of Women and Children's Health, King's College London, London, UK
| | - A Lövgren-Sandblom
- Department of Laboratory Medicine, Karolinska Institute, Stockholm, Sweden
| | - J Chambers
- Division of Women and Children's Health, King's College London, London, UK.,Women's Health Research Centre, Imperial College Healthcare NHS Trust, London, UK
| | - S Begum
- Division of Women and Children's Health, King's College London, London, UK
| | - P Seed
- Division of Women and Children's Health, King's College London, London, UK
| | - I Walker
- Clinical Biochemistry, Frimley Health NHS trust, Wexham Park Hospital, Slough, UK
| | - L C Chappell
- Division of Women and Children's Health, King's College London, London, UK
| | - H-U Marschall
- Department of Molecular and Clinical Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - C Williamson
- Division of Women and Children's Health, King's College London, London, UK
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15
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Perna C, Williamson C, Khaksar S. EP-1540 A bowel pathway for patients undergoing radiotherapy for prostate cancer. Radiother Oncol 2019. [DOI: 10.1016/s0167-8140(19)31960-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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16
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Perkins R, Williamson C, Lavaud J, Mouget JL, Campbell DA. Time-dependent upregulation of electron transport with concomitant induction of regulated excitation dissipation in Haslea diatoms. Photosynth Res 2018; 137:377-388. [PMID: 29663190 PMCID: PMC6182385 DOI: 10.1007/s11120-018-0508-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 04/11/2018] [Indexed: 06/01/2023]
Abstract
Photoacclimation by strains of Haslea "blue" diatom species H. ostrearia and H. silbo sp. nov. ined. was investigated with rapid light curves and induction-recovery curves using fast repetition rate fluorescence. Cultures were grown to exponential phase under 50 µmol m-2 s-1 photosynthetic available radiation (PAR) and then exposed to non-sequential rapid light curves where, once electron transport rate (ETR) had reached saturation, light intensity was decreased and then further increased prior to returning to near growth light intensity. The non-sequential rapid light curve revealed that ETR was not proportional to the instantaneously applied light intensity, due to rapid photoacclimation. Changes in the effective absorption cross sections for open PSII reaction centres (σPSII') or reaction centre connectivity (ρ) did not account for the observed increases in ETR under extended high light. σPSII' in fact decreased as a function of a time-dependent induction of regulated excitation dissipation Y(NPQ), once cells were at or above a PAR coinciding with saturation of ETR. Instead, the observed increases in ETR under extended high light were explained by an increase in the rate of PSII reopening, i.e. QA- oxidation. This acceleration of electron transport was strictly light dependent and relaxed within seconds after a return to low light or darkness. The time-dependent nature of ETR upregulation and regulated NPQ induction was verified using induction-recovery curves. Our findings show a time-dependent induction of excitation dissipation, in parallel with very rapid photoacclimation of electron transport, which combine to make ETR independent of short-term changes in PAR. This supports a selective advantage for these diatoms when exposed to fluctuating light in their environment.
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Affiliation(s)
- R Perkins
- School of Earth and Ocean Sciences, Cardiff University, Park Place, Cardiff, Wales, CF10 3AT, UK.
| | - C Williamson
- School of Earth and Ocean Sciences, Cardiff University, Park Place, Cardiff, Wales, CF10 3AT, UK
- Schools of Biological and Geographical Sciences, University of Bristol, 12 Berkeley Square, Bristol, BS8 1SS, UK
| | - J Lavaud
- UMI 3376 Takuvik, CNRS/Université Laval, Département de Biologie-Pavillon Alexandre Vachon, Québec, QC, G1V 0A6, Canada
| | - J-L Mouget
- Mer-Molécules-Santé (MMS), FR CNRS 3473 IUML, Le Mans Université, Av. O. Messiaen, 72085, Le Mans Cedex 9, France
| | - D A Campbell
- Department of Biology, Mount Allison University, Sackville, NB, E4L3M7, Canada
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17
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Quartermaine G, Lambert K, Rees K, Seed PT, Dhanjal MK, Knight M, McCance DR, Williamson C. Hormone-secreting adrenal tumours cause severe hypertension and high rates of poor pregnancy outcome; a UK Obstetric Surveillance System study with case control comparisons. BJOG 2017; 125:719-727. [DOI: 10.1111/1471-0528.14918] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/17/2017] [Indexed: 11/29/2022]
Affiliation(s)
- G Quartermaine
- Division of Women's Health; King's College London; London UK
| | - K Lambert
- Royal Hampshire County Hospital (RHCH); Winchester UK
| | - K Rees
- Division of Women's Health; King's College London; London UK
| | - PT Seed
- Division of Women's Health; King's College London; London UK
| | - MK Dhanjal
- Directorate of Maternity; Queen Charlotte's and Chelsea Hospital; Imperial College Healthcare NHS Trust; London UK
| | - M Knight
- National Perinatal Epidemiology Unit; Nuffield Department of Population Health; University of Oxford; Oxford UK
| | - DR McCance
- Regional Centre for Endocrinology and Diabetes; Royal Victoria Hospital; Belfast UK
| | - C Williamson
- Division of Women's Health; King's College London; London UK
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18
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Sands J, Reiger-Christ K, Sullivan T, Williamson C, Burks E. P2.13-018 Clinical Outcomes Stage I/0 Adenocarcinoma Lung Diagnosed by Low Dose CT (LDCT) Screening vs Incidentally Discovered. J Thorac Oncol 2017. [DOI: 10.1016/j.jtho.2017.09.1365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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19
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Mabvakure B, Scheepers C, Nonyane M, Lambson B, Madzorera S, Kitchin D, Bhiman J, Wibmer K, Abdool Karim S, Williamson C, Morris L, Moore PL. A38 Diversity analyses of HIV-1 envelope glycoproteins in HIV-infected individuals with and without broadly neutralizing antibodies. Virus Evol 2017; 3:vew036.037. [PMID: 28845277 PMCID: PMC5565991 DOI: 10.1093/ve/vew036.037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- B Mabvakure
- National Health Laboratory Service, Center for HIV and STIs, National Institute for Communicable Diseases, Johannesburg
| | - C Scheepers
- National Health Laboratory Service, Center for HIV and STIs, National Institute for Communicable Diseases, Johannesburg
| | - M Nonyane
- National Health Laboratory Service, Center for HIV and STIs, National Institute for Communicable Diseases, Johannesburg
| | - B Lambson
- National Health Laboratory Service, Center for HIV and STIs, National Institute for Communicable Diseases, Johannesburg
| | - S Madzorera
- National Health Laboratory Service, Center for HIV and STIs, National Institute for Communicable Diseases, Johannesburg
| | - D Kitchin
- National Health Laboratory Service, Center for HIV and STIs, National Institute for Communicable Diseases, Johannesburg
| | - J Bhiman
- National Health Laboratory Service, Center for HIV and STIs, National Institute for Communicable Diseases, Johannesburg
| | - K Wibmer
- National Health Laboratory Service, Center for HIV and STIs, National Institute for Communicable Diseases, Johannesburg
| | - S Abdool Karim
- Centre for the AIDS Programme of Research in South Africa (CAPRISA), Kwa-Zulu Natal
| | - C Williamson
- Centre for the AIDS Programme of Research in South Africa (CAPRISA), Kwa-Zulu Natal
| | - L Morris
- National Health Laboratory Service, Center for HIV and STIs, National Institute for Communicable Diseases, Johannesburg
| | - P L Moore
- National Health Laboratory Service, Center for HIV and STIs, National Institute for Communicable Diseases, Johannesburg
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20
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Dunne EM, Gordon H, Kurten A, Almeida J, Duplissy J, Williamson C, Ortega IK, Pringle KJ, Adamov A, Baltensperger U, Barmet P, Benduhn F, Bianchi F, Breitenlechner M, Clarke A, Curtius J, Dommen J, Donahue NM, Ehrhart S, Flagan RC, Franchin A, Guida R, Hakala J, Hansel A, Heinritzi M, Jokinen T, Kangasluoma J, Kirkby J, Kulmala M, Kupc A, Lawler MJ, Lehtipalo K, Makhmutov V, Mann G, Mathot S, Merikanto J, Miettinen P, Nenes A, Onnela A, Rap A, Reddington CLS, Riccobono F, Richards NAD, Rissanen MP, Rondo L, Sarnela N, Schobesberger S, Sengupta K, Simon M, Sipila M, Smith JN, Stozkhov Y, Tome A, Trostl J, Wagner PE, Wimmer D, Winkler PM, Worsnop DR, Carslaw KS. Global atmospheric particle formation from CERN CLOUD measurements. Science 2016; 354:1119-1124. [DOI: 10.1126/science.aaf2649] [Citation(s) in RCA: 213] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Accepted: 10/12/2016] [Indexed: 11/03/2022]
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21
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Jayasena C, Abbara A, Comninos A, Narayanaswamy S, Gonzalez Maffe J, Izzi-Engbeaya C, Oldham J, Lee T, Sarang Z, Malik Z, Dhanjal M, Williamson C, Regan L, Bloom S, Dhillo W. Novel circulating placental markers prokineticin-1, soluble fms-like tyrosine kinase-1, soluble endoglin and placental growth factor and association with late miscarriage. Hum Reprod 2016; 31:2681-2688. [DOI: 10.1093/humrep/dew225] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 08/02/2016] [Accepted: 08/11/2016] [Indexed: 11/14/2022] Open
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22
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Moosa Y, Garrett N, Gray C, Naranbhai V, Williamson C, Abdool-Karim S. 6 HIV virological controllers in an African cohort. J Virus Erad 2016. [DOI: 10.1016/s2055-6640(20)30951-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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23
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Hardy E, Williamson C, Sewell G. An evaluation of six infusion devices for the continuous infusion of cytotoxic drugs in ambulatory patients. J Oncol Pharm Pract 2016. [DOI: 10.1177/107815529500100102] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Introduction. The clinical, economic, and user attributes of six ambulatory infusion devices were evaluated for their inclusion into the Home Oncol ogy Program, Exeter (HOPE). Methods. Devices evaluated included; Graseby MS-26 syringe driver, Graseby 9100, Pharmacia CADD-1, Parker-Strato 2100 micropump (now un available), Baxter Multiday Infusor, and Infu-med 300. Criteria evaluated included accuracy, preci sion, in-use observations, capital cost, consumable cost, estimated monthly cost, degree of patient intervention, and patient comfort. A quality of life evaluation was undertaken in a more detailed assessment on the Graseby MS-26 and Infu-Med 300 device used routinely in the HOPE pro gramme. Results. On the basis of these studies, the Parker-Strato 2100 pump was the preferred device although this has subsequently been withdrawn from the market. However, the newly developed Graseby 9000 series device was found to possess many of the qualities of the Parker-Strato pump and has been selected for further trials in this institu tion.
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Affiliation(s)
- E.M. Hardy
- Medicines Research Unit, Department of Pharmacy, Royal Devon & Exeter Hospital, Exeter, United Kingdom
| | - C. Williamson
- Medicines Research Unit, Department of Pharmacy, Royal Devon & Exeter Hospital, Exeter, United Kingdom
| | - G.J. Sewell
- Medicines Research Unit, Department of Pharmacy, Royal Devon & Exeter Hospital, Exeter, United Kingdom
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Bianchi F, Tröstl J, Junninen H, Frege C, Henne S, Hoyle CR, Molteni U, Herrmann E, Adamov A, Bukowiecki N, Chen X, Duplissy J, Gysel M, Hutterli M, Kangasluoma J, Kontkanen J, Kürten A, Manninen HE, Münch S, Peräkylä O, Petäjä T, Rondo L, Williamson C, Weingartner E, Curtius J, Worsnop DR, Kulmala M, Dommen J, Baltensperger U. New particle formation in the free troposphere: A question of chemistry and timing. Science 2016; 352:1109-12. [PMID: 27226488 DOI: 10.1126/science.aad5456] [Citation(s) in RCA: 141] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2015] [Accepted: 03/29/2016] [Indexed: 11/02/2022]
Abstract
New particle formation (NPF) is the source of over half of the atmosphere's cloud condensation nuclei, thus influencing cloud properties and Earth's energy balance. Unlike in the planetary boundary layer, few observations of NPF in the free troposphere exist. We provide observational evidence that at high altitudes, NPF occurs mainly through condensation of highly oxygenated molecules (HOMs), in addition to taking place through sulfuric acid-ammonia nucleation. Neutral nucleation is more than 10 times faster than ion-induced nucleation, and growth rates are size-dependent. NPF is restricted to a time window of 1 to 2 days after contact of the air masses with the planetary boundary layer; this is related to the time needed for oxidation of organic compounds to form HOMs. These findings require improved NPF parameterization in atmospheric models.
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Affiliation(s)
- F Bianchi
- Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, 5232 Villigen, Switzerland. Institute for Atmospheric and Climate Science, ETH Zurich, 8092 Zurich, Switzerland. Department of Physics, University of Helsinki, 00014 Helsinki, Finland.
| | - J Tröstl
- Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, 5232 Villigen, Switzerland
| | - H Junninen
- Department of Physics, University of Helsinki, 00014 Helsinki, Finland
| | - C Frege
- Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, 5232 Villigen, Switzerland
| | - S Henne
- Empa, Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland
| | - C R Hoyle
- Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, 5232 Villigen, Switzerland. WSL (Swiss Federal Institute for Forest, Snow and Landscape Research) Institute for Snow and Avalanche Research SLF, 7260 Davos, Switzerland
| | - U Molteni
- Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, 5232 Villigen, Switzerland
| | - E Herrmann
- Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, 5232 Villigen, Switzerland
| | - A Adamov
- Department of Physics, University of Helsinki, 00014 Helsinki, Finland
| | - N Bukowiecki
- Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, 5232 Villigen, Switzerland
| | - X Chen
- Department of Physics, University of Helsinki, 00014 Helsinki, Finland
| | - J Duplissy
- Department of Physics, University of Helsinki, 00014 Helsinki, Finland. Helsinki Institute of Physics, University of Helsinki, 00014 Helsinki, Finland
| | - M Gysel
- Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, 5232 Villigen, Switzerland
| | | | - J Kangasluoma
- Department of Physics, University of Helsinki, 00014 Helsinki, Finland
| | - J Kontkanen
- Department of Physics, University of Helsinki, 00014 Helsinki, Finland
| | - A Kürten
- Institute for Atmospheric and Environmental Sciences, Goethe University Frankfurt, 60438 Frankfurt am Main, Germany
| | - H E Manninen
- Department of Physics, University of Helsinki, 00014 Helsinki, Finland
| | - S Münch
- Institute for Atmospheric and Environmental Sciences, Goethe University Frankfurt, 60438 Frankfurt am Main, Germany
| | - O Peräkylä
- Department of Physics, University of Helsinki, 00014 Helsinki, Finland
| | - T Petäjä
- Department of Physics, University of Helsinki, 00014 Helsinki, Finland
| | - L Rondo
- Institute for Atmospheric and Environmental Sciences, Goethe University Frankfurt, 60438 Frankfurt am Main, Germany
| | - C Williamson
- Institute for Atmospheric and Environmental Sciences, Goethe University Frankfurt, 60438 Frankfurt am Main, Germany
| | - E Weingartner
- Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, 5232 Villigen, Switzerland
| | - J Curtius
- Institute for Atmospheric and Environmental Sciences, Goethe University Frankfurt, 60438 Frankfurt am Main, Germany
| | - D R Worsnop
- Department of Physics, University of Helsinki, 00014 Helsinki, Finland. Aerodyne Research, Billerica, MA 01821, USA
| | - M Kulmala
- Department of Physics, University of Helsinki, 00014 Helsinki, Finland
| | - J Dommen
- Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, 5232 Villigen, Switzerland
| | - U Baltensperger
- Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, 5232 Villigen, Switzerland.
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Rondo L, Ehrhart S, Kürten A, Adamov A, Bianchi F, Breitenlechner M, Duplissy J, Franchin A, Dommen J, Donahue NM, Dunne EM, Flagan RC, Hakala J, Hansel A, Keskinen H, Kim J, Jokinen T, Lehtipalo K, Leiminger M, Praplan A, Riccobono F, Rissanen MP, Sarnela N, Schobesberger S, Simon M, Sipilä M, Smith JN, Tomé A, Tröstl J, Tsagkogeorgas G, Vaattovaara P, Winkler PM, Williamson C, Wimmer D, Baltensperger U, Kirkby J, Kulmala M, Petäjä T, Worsnop DR, Curtius J. Effect of dimethylamine on the gas phase sulfuric acid concentration measured by Chemical Ionization Mass Spectrometry. J Geophys Res Atmos 2016; 121:3036-3049. [PMID: 27610289 PMCID: PMC4996328 DOI: 10.1002/2015jd023868] [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] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 10/15/2015] [Accepted: 11/09/2015] [Indexed: 06/06/2023]
Abstract
Sulfuric acid is widely recognized as a very important substance driving atmospheric aerosol nucleation. Based on quantum chemical calculations it has been suggested that the quantitative detection of gas phase sulfuric acid (H2SO4) by use of Chemical Ionization Mass Spectrometry (CIMS) could be biased in the presence of gas phase amines such as dimethylamine (DMA). An experiment (CLOUD7 campaign) was set up at the CLOUD (Cosmics Leaving OUtdoor Droplets) chamber to investigate the quantitative detection of H2SO4 in the presence of dimethylamine by CIMS at atmospherically relevant concentrations. For the first time in the CLOUD experiment, the monomer sulfuric acid concentration was measured by a CIMS and by two CI-APi-TOF (Chemical Ionization-Atmospheric Pressure interface-Time Of Flight) mass spectrometers. In addition, neutral sulfuric acid clusters were measured with the CI-APi-TOFs. The CLOUD7 measurements show that in the presence of dimethylamine (<5 to 70 pptv) the sulfuric acid monomer measured by the CIMS represents only a fraction of the total H2SO4, contained in the monomer and the clusters that is available for particle growth. Although it was found that the addition of dimethylamine dramatically changes the H2SO4 cluster distribution compared to binary (H2SO4-H2O) conditions, the CIMS detection efficiency does not seem to depend substantially on whether an individual H2SO4 monomer is clustered with a DMA molecule. The experimental observations are supported by numerical simulations based on A Self-contained Atmospheric chemistry coDe coupled with a molecular process model (Sulfuric Acid Water NUCleation) operated in the kinetic limit.
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Williamson C, Pandey A. P-031 a retrospective evaluation of the potential for emergency aneurysm repair to reduce the incidence of rebleeding. J Neurointerv Surg 2015. [DOI: 10.1136/neurintsurg-2015-011917.70] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Bebb G, Elegbede A, Petersen L, Williamson C, Lees-Miller S. Identifying ATMic non-small cell lung cancer cell lines: Implications for designing clinical trials. Ann Oncol 2015. [DOI: 10.1093/annonc/mdv095.7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Jayasena CN, Abbara A, Izzi-Engbeaya C, Comninos AN, Harvey RA, Gonzalez Maffe J, Sarang Z, Ganiyu-Dada Z, Padilha AI, Dhanjal M, Williamson C, Regan L, Ghatei MA, Bloom SR, Dhillo WS. Reduced levels of plasma kisspeptin during the antenatal booking visit are associated with increased risk of miscarriage. J Clin Endocrinol Metab 2014; 99:E2652-60. [PMID: 25127195 PMCID: PMC4255122 DOI: 10.1210/jc.2014-1953] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Kisspeptin is a recently identified hormone encoded by the KISS1 gene, playing a critical role in human reproduction. Plasma kisspeptin levels rise dramatically during normal pregnancy due to placental synthesis, which implicates it as a potential tool for assessing risks of pregnancy complications. No previous prospective study has investigated the association between plasma kisspeptin and risk of miscarriage. OBJECTIVE The objective of the study was to determine whether a single plasma kisspeptin or serum human chorionic gonadotropin (hCG) measurement in asymptomatic women attending their booking antenatal visit is associated with miscarriage. DESIGN This was a prospective cohort study. SETTING The study was conducted at a tertiary obstetric center. PARTICIPANTS A total of 993 asymptomatic pregnant women with a gestation of 6 weeks or longer attending routine antenatal booking visit were recruited between January 2010 and December 2012. MAIN OUTCOME MEASURES Plasma kisspeptin and serum hCG were measured during the antenatal booking visit. Pregnancy outcome was recorded prospectively. RESULTS Plasma kisspeptin correlated with gestation (r(2) = 0.57; P < .0001). Gestational age-corrected (multiples of median) plasma kisspeptin was 60.4% lower (P < .001), and multiples of median-hCG was 36.1% lower (P < .001) in women later diagnosed with miscarriage compared with women without miscarriage. Increased plasma kisspeptin was associated with reduced miscarriage risk, even after adjusting for age, body mass index, gestational age, smoking, and blood pressure [odds ratio 0.13 (95% confidence interval 0.08-0.22), P = .0001]. Kisspeptin had a higher diagnostic performance for miscarriage than hCG (receiver-operator characteristic-area under the curve 0.899 ± 0.025 plasma kisspeptin; 0.775 ± 0.040, serum hCG, P < .01 vs plasma kisspeptin). CONCLUSION Our data suggest for the first time that a single plasma kisspeptin measurement taken during the antenatal booking visit provides a potential novel marker for identifying asymptomatic pregnant women at a gestation of 6 weeks or greater at increased risk of miscarriage.
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Affiliation(s)
- C N Jayasena
- Section of Investigative Medicine (C.N.J., A.A., A.I.-E., A.N.C., Z.S., Z.G.-D., M.A.G., S.R.B., W.S.D.) and Imperial Clinical Trials Unit (H.G.M.), Imperial College London, London W12 ONN, United Kingdom; Medical Oncology Laboratory (R.A.H., A.I.P.), Charing Cross Hospital Campus, Imperial College National Health Service Healthcare Trust, London W6 8RF, United Kingdom; Department of Obstetrics and Gynaecology (M.D.), Queen Charlotte's Hospital, Imperial College National Health Service Healthcare Trust, London W12 0HS, United Kingdom; Department Obstetrics and Gynaecology (C.W.), King's College London, London SE5 9PJ, United Kingdom; and Department of Obstetrics and Gynaecology (L.R.), St Mary's Hospital, Imperial College National Health Service Healthcare Trust, London W2 1NY, United Kingdom
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Martineau M, Papacleovoulou G, Abu-Hayyeh S, Dixon P, Ji H, Powrie R, Larson L, Chien E, Williamson C. Cholestatic pregnancy is associated with reduced placental 11βHSD2 expression. Placenta 2014; 35:37-43. [DOI: 10.1016/j.placenta.2013.10.019] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2013] [Revised: 10/22/2013] [Accepted: 10/23/2013] [Indexed: 12/27/2022]
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Keitel V, Spomer L, Marin J, Williamson C, Geenes V, Kubitz R, Häussinger D, Macias R. Effect of maternal cholestasis on TGR5 expression in human and rat placenta at term. Placenta 2013; 34:810-6. [DOI: 10.1016/j.placenta.2013.06.302] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Revised: 05/31/2013] [Accepted: 06/18/2013] [Indexed: 01/26/2023]
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Gurung V, Chappell L, Seed P, Chambers J, Williamson C, Thornton J. O293 PITCH: URSODEOXYCHOLIC ACID VERSUS PLACEBO, AND EARLY DELIVERY VERSUS EXPECTANT MANAGEMENT IN THE MANAGEMENT OF INTRAHEPATIC CHOLESTASIS OF PREGNANCY: TWO RANDOMISED CONTROLLED TRIALS. Int J Gynaecol Obstet 2012. [DOI: 10.1016/s0020-7292(12)60723-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Nofemela A, Bandawe G, Thebus R, Marais J, Maboko L, Hoelscher M, Williamson C, Woodman Z. Characterization of envelope function of transmitted viruses circulating in Mbeya, Tanzania, and its impact on disease progression. Retrovirology 2012. [PMCID: PMC3441964 DOI: 10.1186/1742-4690-9-s2-p144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Zembe L, Tongo M, Ebong E, Ngobe EM, Williamson C, Burgers W. The recognition of HIV-1 consensus group M Gag and Nef peptide reagents in mono- and multi-clade epidemics: implications for HIV vaccine design. Retrovirology 2012. [PMCID: PMC3441941 DOI: 10.1186/1742-4690-9-s2-p253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Chege GK, Burgers W, Muller T, Shephard EG, Williamson C, Williamson A. A single dose of SAAVI MVA-C reboosts rhesus macaques after more than 3 years post DNA-MVA prime-boost vaccination. Retrovirology 2012. [PMCID: PMC3441556 DOI: 10.1186/1742-4690-9-s2-p32] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
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Geenes VL, Lim YH, Bowman N, Tailor H, Dixon PH, Chambers J, Brown L, Wyatt-Ashmead J, Bhakoo K, Williamson C. A placental phenotype for intrahepatic cholestasis of pregnancy. Placenta 2011; 32:1026-32. [PMID: 22015023 DOI: 10.1016/j.placenta.2011.09.006] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2011] [Revised: 08/23/2011] [Accepted: 09/06/2011] [Indexed: 12/23/2022]
Abstract
Intrahepatic cholestasis of pregnancy (ICP) is a pregnancy specific liver disease associated with significant risk of fetal complications. It is hypothesised that the risk of adverse fetal outcomes relates to the toxic effects of bile acids, the levels of which are increased in both maternal and fetal serum. Human and rodent studies have shown that transplacental transfer of bile acids is impaired in ICP. Furthermore, the morphology of placentas from the rodent model of ICP is markedly abnormal, and is associated with increased expression of apoptotic markers and oxidative stress. Using placental tissue from ICP cases and normal pregnancies and cultured placental explant fragments we investigated the histological and molecular effects of cholestasis. We also examined the influence of ursodeoxycholic acid (UDCA) administration on these parameters. Here we report that ICP is associated with several morphological abnormalities of the placenta, including an increase in the number of syncytial knots, and that these can be reproduced in an in vitro (explant) model exposed to the bile acids taurocholic acid and taurochenodoexycholic acid. Furthermore, we demonstrate that ursodeoxycholic acid, a drug commonly used in the management of ICP, has a protective effect on placental tissue both in vivo and in vitro.
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Affiliation(s)
- V L Geenes
- Institute of Reproductive and Developmental Biology, Imperial College London, Du Cane Road, London W12 0NN, UK
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Gleeson DF, Williamson C, Grasby SE, Pappalardo RT, Spear JR, Templeton AS. Low temperature S(0) biomineralization at a supraglacial spring system in the Canadian High Arctic. Geobiology 2011; 9:360-375. [PMID: 21592302 DOI: 10.1111/j.1472-4669.2011.00283.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Elemental sulfur (S(0) ) is deposited each summer onto surface ice at Borup Fiord pass on Ellesmere Island, Canada, when high concentrations of aqueous H(2) S are discharged from a supraglacial spring system. 16S rRNA gene clone libraries generated from sulfur deposits were dominated by β-Proteobacteria, particularly Ralstonia sp. Sulfur-cycling micro-organisms such as Thiomicrospira sp., and ε-Proteobacteria such as Sulfuricurvales and Sulfurovumales spp. were also abundant. Concurrent cultivation experiments isolated psychrophilic, sulfide-oxidizing consortia, which produce S(0) in opposing gradients of Na(2) S and oxygen. 16S rRNA gene analyses of sulfur precipitated in gradient tubes show stable sulfur-biomineralizing consortia dominated by Marinobacter sp. in association with Shewanella, Loktanella, Rubrobacter, Flavobacterium, and Sphingomonas spp. Organisms closely related to cultivars appear in environmental 16S rRNA clone libraries; none currently known to oxidize sulfide. Once consortia were simplified to Marinobacter and Flavobacteria spp. through dilution-to-extinction and agar removal, sulfur biomineralization continued. Shewanella, Loktanella, Sphingomonas, and Devosia spp. were also isolated on heterotrophic media, but none produced S(0) alone when reintroduced to Na(2) S gradient tubes. Tubes inoculated with a Marinobacter and Shewanella spp. co-culture did show sulfur biomineralization, suggesting that Marinobacter may be the key sulfide oxidizer in laboratory experiments. Light, florescence and scanning electron microscopy of mineral aggregates produced in Marinobacter experiments revealed abundant cells, with filaments and sheaths variably mineralized with extracellular submicron sulfur grains; similar biomineralization was not observed in abiotic controls. Detailed characterization of mineral products associated with low temperature microbial sulfur-cycling may provide biosignatures relevant to future exploration of Europa and Mars.
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Affiliation(s)
- D F Gleeson
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA.
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Mosha F, Urassa W, Aboud S, Lyamuya E, Sandstrom E, Bredell H, Williamson C. Prevalence of genotypic resistance to antiretroviral drugs in treatment-naive youths infected with diverse HIV type 1 subtypes and recombinant forms in Dar es Salaam, Tanzania. AIDS Res Hum Retroviruses 2011; 27:377-82. [PMID: 20954839 DOI: 10.1089/aid.2010.0113] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
As human immunodeficiency virus (HIV) diversity may have an impact on both vaccine efficacy and drug resistance, it is important to have knowledge of circulating genetic variants. With widespread use of antiretroviral (ARV) drugs in Africa, one of the major potential challenges is the risk of emergence of ARV drug-resistant HIV strains. This study aimed to determine the circulating HIV subtypes and recombinant forms, as well as the prevalence of ARV drug resistance mutations, among 75 treatment-naive HIV-infected youths in Dar es Salaam, Tanzania. Gag (n = 48), partial pol (n = 44), and partial env (n = 35) sequencing was performed; all three regions were sequenced in 26 samples. Evidence of infection with recombinant viruses was found in 12 (46%) participants; AC recombinants were the most commonly detected and they were identified in six (23%) participants. Of individuals infected with nonrecombinant strains, subtype A was most commonly detected in seven (27%) participants, followed by subtype C detected in six (23%) participants and subtype D detected in one (4%) participant. Among the pol sequences from 44 individuals, three (7%) had resistance to nucleoside reverse transcriptase (RT) inhibitors and four (9%) had nonnucleoside RT inhibitor resistance mutations. Of these, three (7%) individuals were infected with viruses with cross-resistance mutations to both classes of RT inhibitors. These resistant mutations were all associated with drugs currently used in first-line therapy and in the prevention of vertical transmission. This high prevalence of resistance mutations is of considerable concern in apparently drug-naive populations as it may result in treatment failure and the spread of ARV-resistant strains.
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Affiliation(s)
- F. Mosha
- Field Epidemiology and Laboratory Training Programme, Ministry of Health and Social Welfare, Dar es Salaam, Tanzania
| | - W. Urassa
- Department of Microbiology and Immunology, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | - S. Aboud
- Department of Microbiology and Immunology, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | - E. Lyamuya
- Department of Microbiology and Immunology, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | - E. Sandstrom
- Department of Clinical Science and Education, Sodersjukhuset and Karolinska Institutet, Stockholm, Sweden
| | - H. Bredell
- Institute of Infectious Disease and Molecular Medicine, Division of Medical Virology, University of Cape Town, Cape Town, South Africa
| | - C. Williamson
- Institute of Infectious Disease and Molecular Medicine, Division of Medical Virology, University of Cape Town, Cape Town, South Africa
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Breitmeryer BG, Brown JM, Leighty KA, Williamson C. Configuration and distance interact to determine object- or space-based attetnional deployment. J Vis 2010. [DOI: 10.1167/2.7.14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Kenyon AP, Tribe RM, Nelson-Piercy C, Girling JC, Williamson C, Seed PT, Vaughan-Jones S, Shennan AH. Pruritus in pregnancy: a study of anatomical distribution and prevalence in relation to the development of obstetric cholestasis. Obstet Med 2010; 3:25-9. [PMID: 27582836 DOI: 10.1258/om.2010.090055] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/26/2010] [Indexed: 12/27/2022] Open
Abstract
The main objective of this study was to determine the prevalence and anatomical distribution of pruritus in 6532 pregnant women from a UK antenatal population. Pregnant women attending and completing antenatal care at two general hospitals over a 12-month period were recruited and contacted on three occasions by post. Medical advice and a questionnaire detailing the nature and severity of their pruritus were included. Pruritus in pregnancy, as reported by questionnaire, affected approximately 23% of pregnancies (n = 1521/6532 women) and 1.6% (n = 25) of these women developed obstetric cholestasis (OC). Overall, 0.66% of the antenatal population (43/6532) had a clinical diagnosis of OC (95% CI: 0.48-0.89%). Itching unrelated to OC was most commonly reported to be worst on the abdomen (31%, 616/2014). Women with OC reported pruritus to be most severe on the palms and soles in 16% (4/25) and 'all over' in 24% (6/25) compared with 5% (54/1120) (P < 0.05) and 4% (42/1120, P < 0.0001) of those without OC. In conclusion, pruritus affected approximately one in four women and OC one in 135 women during the study period. Women whose pruritus is 'all over' or most severe on the 'palms or soles' may be at greater risk of the disease.
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Affiliation(s)
- A P Kenyon
- Maternal and Fetal Research Unit, Division of Reproduction and Endocrinology, King's College
| | - R M Tribe
- Maternal and Fetal Research Unit, Division of Reproduction and Endocrinology, King's College
| | - C Nelson-Piercy
- Maternal and Fetal Research Unit, Division of Reproduction and Endocrinology, King's College
| | | | | | - P T Seed
- Maternal and Fetal Research Unit, Division of Reproduction and Endocrinology, King's College
| | - S Vaughan-Jones
- Department of Dermatology, St Peter's Hospital Chertsey , Surrey , UK
| | - A H Shennan
- Maternal and Fetal Research Unit, Division of Reproduction and Endocrinology, King's College
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Moore P, Gray E, Madiga M, Ranchobe N, Lambson B, Abrahams MR, Bandawe G, Sheward D, Thebus R, Mlisana K, Karim SA, Williamson C, Morris L. Understanding Anti-HIV Antibody Targets. Int J Infect Dis 2010. [DOI: 10.1016/j.ijid.2010.02.1529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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Williamson C, Yüregir H. Obesity - a reality check? Towards a deeper understanding. NUTR BULL 2009. [DOI: 10.1111/j.1467-3010.2009.01789.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Treurnicht FK, Seoighe C, Martin DP, Wood N, Abrahams MR, Rosa DDA, Bredell H, Woodman Z, Hide W, Mlisana K, Karim SA, Gray CM, Williamson C. Adaptive changes in HIV-1 subtype C proteins during early infection are driven by changes in HLA-associated immune pressure. Virology 2009; 396:213-25. [PMID: 19913270 DOI: 10.1016/j.virol.2009.10.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2009] [Revised: 07/21/2009] [Accepted: 10/04/2009] [Indexed: 01/12/2023]
Abstract
It is unresolved whether recently transmitted human immunodeficiency viruses (HIV) have genetic features that specifically favour their transmissibility. To identify potential "transmission signatures", we compared 20 full-length HIV-1 subtype C genomes from primary infections, with 66 sampled from ethnically and geographically matched individuals with chronic infections. Controlling for recombination and phylogenetic relatedness, we identified 39 sites at which amino acid frequency spectra differed significantly between groups. These sites were predominantly located within Env, Pol and Gag (14/39, 9/39 and 6/39 respectively) and were significantly clustered (33/39) within known immunoreactive peptides. Within 6 months of infection, we detected reversion-to-consensus mutations at 14 sites and potential CTL escape mutations at seven. Here we provide evidence that frequent reversion mutations probably allows the virus to recover replicative fitness which, together with immune escape driven by the HLA alleles of the new hosts, differentiate sequences from chronic infections from those sampled shortly after transmission.
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Affiliation(s)
- F K Treurnicht
- Institute of Infectious Diseases and Molecular Medicine (IIDMM), Division of Medical Virology, University of Cape Town, South Africa
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Moore PL, Ranchobe N, Lambson B, Gray E, Mlisana K, Karim SA, Williamson C, Gnanakaran S, Morris L. P09-04. Charge changes in the alpha2-helix in the C3 region of the HIV-1 subtype C envelope mediate neutralization escape. Retrovirology 2009. [PMCID: PMC2767601 DOI: 10.1186/1742-4690-6-s3-p117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Gray E, Moore P, Ranchobe N, Abrahams M, Madiga M, Mlisana K, Abdool-Karim S, Williamson C, Morris L. P04-06. Evolution of an anti-MPER gp41 antibody response that mediates broad HIV-1 cross-neutralization. Retrovirology 2009. [PMCID: PMC2767848 DOI: 10.1186/1742-4690-6-s3-p34] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
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Sanchez A, Shewchuk R, Parish S, Cheatham C, Williamson C, Abdolrasulnia M. Predictors of OB/GYN intentions to initiate a discussion about women's sexual health with premenopausal patients. Fertil Steril 2009. [DOI: 10.1016/j.fertnstert.2009.07.1200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Affiliation(s)
- A Chrisoulidou
- Institute of Reproductive and Developmental Biology, Queen Charlotte's and Chelsea Hospital, London, UK
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Diac M, Kenyon A, Nelson-Piercy C, Girling J, Cheng F, Tribe RM, Goodman J, Shennan A, Williamson C. Dexamethasone in the treatment of obstetric cholestasis: A case series. J OBSTET GYNAECOL 2009; 26:110-4. [PMID: 16483964 DOI: 10.1080/01443610500443246] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [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: 10/23/2022]
Abstract
Twelve women with obstetric cholestasis were given dexamethasone after failure to respond to ursodeoxycholic acid. Clinical improvement was achieved in eight cases, without complete resolution of symptoms. Biochemical response was achieved in seven cases. All but two cases had good correlation between clinical and biochemical response. Women of Asian and South American origin were more likely to respond to dexamethasone than Caucasians. There were no reported maternal or fetal side-effects. However, the subsequent consequences of dexamethasone treatment for the mother and fetus have not been thoroughly evaluated. Therefore, even in Asian and South American women, larger studies of dexamethasone are required before this treatment can be recommended as a universally safe and effective treatment for obstetric cholestasis.
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Affiliation(s)
- M Diac
- Institute of Reproductive and Developmental Biology, Imperial College London, Hammersmith Campus, Du Cane Road, London W12 0NN, UK
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Banerjee A, Wynne K, Tan T, Hatfield EC, Martin NM, Williamson C, Meeran K. High dose cabergoline therapy for a resistant macroprolactinoma during pregnancy. Clin Endocrinol (Oxf) 2009; 70:812-3. [PMID: 18803677 DOI: 10.1111/j.1365-2265.2008.03425.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Dixon PH, van Mil SWC, Chambers J, Strautnieks S, Thompson RJ, Lammert F, Kubitz R, Keitel V, Glantz A, Mattsson LA, Marschall HU, Molokhia M, Moore GE, Linton KJ, Williamson C. Contribution of variant alleles of ABCB11 to susceptibility to intrahepatic cholestasis of pregnancy. Gut 2009; 58:537-44. [PMID: 18987030 DOI: 10.1136/gut.2008.159541] [Citation(s) in RCA: 142] [Impact Index Per Article: 9.5] [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] [Indexed: 12/12/2022]
Abstract
BACKGROUND Intrahepatic cholestasis of pregnancy (ICP) has a complex aetiology with a significant genetic component. ABCB11 encodes the bile salt export pump (BSEP); mutations cause a spectrum of cholestatic disease, and are implicated in the aetiology of ICP. METHODS ABCB11 variation in ICP was investigated by screening for five mutant alleles (E297G, D482G, N591S, D676Y and G855R) and the V444A polymorphism (c.1331T>C, rs2287622) in two ICP cohorts (n = 333 UK, n = 158 continental Europe), and controls (n = 261) for V444A. PCR primers were used to amplify and sequence patient and control DNA. The molecular basis for the observed phenotypes was investigated in silico by analysing the equivalent residues in the structure of the homologous bacterial transporter Sav1866. RESULTS E297G was observed four times and D482G once. N591S was present in two patients; D676Y and G855R were not observed. The V444A polymorphism was associated with ICP (allelic analysis for C vs T: OR 1.7 (95% CI 1.4 to 2.1, p<0.001)). In addition, CC homozygotes were more likely to have ICP than TT homozygotes: OR 2.8 (95% CI 1.7 to 4.4 p<0.0001). Structural analyses suggest that E297G and D482G destabilize the protein fold of BSEP. The molecular basis of V444A and N591S was not apparent from the Sav1866 structure. CONCLUSIONS Heterozygosity for the common ABCB11 mutations accounts for 1% of European ICP cases; these two mutants probably reduce the folding efficiency of BSEP. N591S is a recurrent mutation; however, the mechanism may be independent of protein stability or function. The V444A polymorphism is a significant risk factor for ICP in this population.
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Affiliation(s)
- P H Dixon
- Maternal and Fetal Disease Group, Institute of Reproductive and Developmental Biology, Imperial College London, London, UK
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Owen BM, Van Mil SWC, Boudjelal M, McLay I, Cairns W, Elias E, White R, Williamson C, Dixon PH. Sequencing and functional assessment of hPXR (NR1I2) variants in intrahepatic cholestasis of pregnancy. Xenobiotica 2008; 38:1289-97. [PMID: 18800312 DOI: 10.1080/00498250802426114] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
1. The purpose of this study was to evaluate the role of coding variation in hPXR (NR1I2) in intrahepatic cholestasis of pregnancy (ICP) and to functionally asses the response of PXR variants to ligands of interest in ICP. 2. The coding region of hPXR was sequenced in a cohort of 121 Caucasian ICP patients and exon 2 was sequenced in an additional 226 cases. Reporter assays were used to evaluate the function of all known hPXR variants in response to the secondary bile acid lithocholic acid and therapeutic agents rifampicin, ursodeoxycholic acid and dexamethasone. 3. Two coding single nucleotide polymorphisms (C79T and G106A) were detected in the ICP cohort at frequencies consistent with healthy populations. These do not alter hPXR function in response to ligands of interest to ICP. Analysis of all known coding hPXR variants demonstrates that while subtle changes in experimental design mask or may unveil the functional effects of genetic variation, these are not maintained in a standard functional assay. 4. Coding genetic variation in hPXR does not contribute to the aetiology of ICP in Caucasian populations.
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Affiliation(s)
- B M Owen
- Maternal and Fetal Disease Group, Institute of Reproductive and Developmental Biology, Imperial College London, London, UK
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