Publications by authors named "Anna Harvey"

31 Publications

COVIDReady2 study protocol: cross-sectional survey of medical student volunteering and education during the COVID-19 pandemic in the United Kingdom.

BMC Med Educ 2021 Apr 14;21(1):211. Epub 2021 Apr 14.

Nuffield Department of Primary Care Health Sciences, Medical Sciences Division, University of Oxford, Oxford, UK.

Background: The coronavirus disease 2019 pandemic has led to global disruption of healthcare. Many students volunteered to provide clinical support. Volunteering to work in a clinical capacity was a unique medical education opportunity; however, it is unknown whether this was a positive learning experience or which volunteering roles were of most benefit to students.

Methods: The COVIDReady2 study is a national cross-sectional study of all medical students at medical schools in the United Kingdom. The primary outcome is to explore the experiences of medical students who volunteered during the pandemic in comparison to those who did not. We will compare responses to determine the educational benefit and issues they faced. In addition to quantitative analysis, thematic analysis will be used to identify themes in qualitative responses.

Discussion: There is a growing body of evidence to suggest that service roles have potential to enhance medical education; yet, there is a shortage of studies able to offer practical advice for how these roles may be incorporated in future medical education. We anticipate that this study will help to identify volunteer structures that have been beneficial for students, so that similar infrastructures can be used in the future, and help inform medical education in a non-pandemic setting.

Trial Registration: Not Applicable.
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http://dx.doi.org/10.1186/s12909-021-02629-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8045566PMC
April 2021

Siȃn Kerwin is an adult nurse.

BMJ 2020 10 21;371:m2064. Epub 2020 Oct 21.

London.

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http://dx.doi.org/10.1136/bmj.m2064DOI Listing
October 2020

Jeannine Watkins is a physician associate.

BMJ 2020 10 16;371:m3858. Epub 2020 Oct 16.

London.

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http://dx.doi.org/10.1136/bmj.m3858DOI Listing
October 2020

Claire Murphy is a mental health nurse.

BMJ 2020 10 14;371:m2068. Epub 2020 Oct 14.

London.

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http://dx.doi.org/10.1136/bmj.m2068DOI Listing
October 2020

Robert Cast is an anatomical pathology technologist.

Authors:
Pat Lok Anna Harvey

BMJ 2020 10 7;371:m3854. Epub 2020 Oct 7.

London.

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http://dx.doi.org/10.1136/bmj.m3854DOI Listing
October 2020

Meet the new editorial scholar: Nikki Nabavi.

Authors:
Anna Harvey

BMJ 2020 09 22;370:m3660. Epub 2020 Sep 22.

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http://dx.doi.org/10.1136/bmj.m3660DOI Listing
September 2020

Hannah Grace is an art therapist.

BMJ 2020 09 7;370:m2318. Epub 2020 Sep 7.

University of Manchester, UK.

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http://dx.doi.org/10.1136/bmj.m2318DOI Listing
September 2020

Tracy Earley is a consultant nurse in nutrition.

BMJ 2020 09 7;370:m2323. Epub 2020 Sep 7.

University of Manchester.

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http://dx.doi.org/10.1136/bmj.m2323DOI Listing
September 2020

Adapting to the unexpected.

Authors:
Anna Harvey

BMJ 2020 08 26;370:m2944. Epub 2020 Aug 26.

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http://dx.doi.org/10.1136/bmj.m2944DOI Listing
August 2020

Covering covid-19: stories from 's news desk.

Authors:
Anna Harvey

BMJ 2020 08 21;370:m2577. Epub 2020 Aug 21.

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http://dx.doi.org/10.1136/bmj.m2577DOI Listing
August 2020

Covid-19: the medical students responding to the pandemic.

BMJ 2020 06 15;369:m2160. Epub 2020 Jun 15.

London, UK.

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http://dx.doi.org/10.1136/bmj.m2160DOI Listing
June 2020

Ten years of Geeky Medics.

Authors:
Anna Harvey

BMJ 2020 May 11;369:m1218. Epub 2020 May 11.

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http://dx.doi.org/10.1136/bmj.m1218DOI Listing
May 2020

Covid-19: medical schools given powers to graduate final year students early to help NHS.

Authors:
Anna Harvey

BMJ 2020 03 26;368:m1227. Epub 2020 Mar 26.

The BMJ.

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http://dx.doi.org/10.1136/bmj.m1227DOI Listing
March 2020

Covid-19: medical students should not work outside their competency, says BMA.

Authors:
Anna Harvey

BMJ 2020 Mar 24;368:m1197. Epub 2020 Mar 24.

The BMJ.

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http://dx.doi.org/10.1136/bmj.m1197DOI Listing
March 2020

Medical memes.

Authors:
Anna Harvey

BMJ 2020 03 13;368:m531. Epub 2020 Mar 13.

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http://dx.doi.org/10.1136/bmj.m531DOI Listing
March 2020

The narrative coherence of witness transcripts in children on the autism spectrum.

Res Dev Disabil 2020 Jan 19;96:103518. Epub 2019 Nov 19.

University of Winchester, Winchester, SO22 4NR, UK. Electronic address:

Background And Aims: Autistic children often recall fewer details about witnessed events than typically developing children (of comparable age and ability), although the information they recall is generally no less accurate. Previous research has not examined the narrative coherence of such accounts, despite higher quality narratives potentially being perceived more favourably by criminal justice professionals and juries. This study compared the narrative coherence of witness transcripts produced by autistic and typically developing (TD) children (ages 6-11 years, IQs 70+).

Methods And Procedures: Secondary analysis was carried out on interview transcripts from a subset of 104 participants (autism = 52, TD = 52) who had taken part in a larger study of eyewitness skills in autistic and TD children. Groups were matched on chronological age, IQ and receptive language ability. Coding frameworks were adopted from existing narrative research, featuring elements of 'story grammar'.

Outcomes And Results: Whilst fewer event details were reported by autistic children, there were no group differences in narrative coherence (number and diversity of 'story grammar' elements used), narrative length or semantic diversity.

Conclusions And Implications: These findings suggest that the narrative coherence of autistic children's witness accounts is equivalent to TD peers of comparable age and ability.
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http://dx.doi.org/10.1016/j.ridd.2019.103518DOI Listing
January 2020

Lyme disease: chronic illness is rare, say experts.

Authors:
Anna Harvey

BMJ 2019 Oct 10;367:l5975. Epub 2019 Oct 10.

The BMJ.

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http://dx.doi.org/10.1136/bmj.l5975DOI Listing
October 2019

Medical school places must double by 2029, says Royal College of Psychiatrists.

Authors:
Anna Harvey

BMJ 2019 Oct 2;367:l5826. Epub 2019 Oct 2.

The BMJ.

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http://dx.doi.org/10.1136/bmj.l5826DOI Listing
October 2019

Identification of a gene regulatory network associated with prion replication.

EMBO J 2014 Jul 19;33(14):1527-47. Epub 2014 May 19.

MRC Prion Unit and Department of Neurodegenerative Disease, UCL Institute of Neurology Queen Square, London, UK

Prions consist of aggregates of abnormal conformers of the cellular prion protein (PrP(C)). They propagate by recruiting host-encoded PrP(C) although the critical interacting proteins and the reasons for the differences in susceptibility of distinct cell lines and populations are unknown. We derived a lineage of cell lines with markedly differing susceptibilities, unexplained by PrP(C) expression differences, to identify such factors. Transcriptome analysis of prion-resistant revertants, isolated from highly susceptible cells, revealed a gene expression signature associated with susceptibility and modulated by differentiation. Several of these genes encode proteins with a role in extracellular matrix (ECM) remodelling, a compartment in which disease-related PrP is deposited. Silencing nine of these genes significantly increased susceptibility. Silencing of Papss2 led to undersulphated heparan sulphate and increased PrP(C) deposition at the ECM, concomitantly with increased prion propagation. Moreover, inhibition of fibronectin 1 binding to integrin α8 by RGD peptide inhibited metalloproteinases (MMP)-2/9 whilst increasing prion propagation. In summary, we have identified a gene regulatory network associated with prion propagation at the ECM and governed by the cellular differentiation state.
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http://dx.doi.org/10.15252/embj.201387150DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4198050PMC
July 2014

DINO (Diet In Nutrients Out) - an integrated dietary assessment system.

Public Health Nutr 2015 Feb 27;18(2):234-41. Epub 2014 Mar 27.

MRC Human Nutrition Research,Elsie Widdowson Laboratory,120 Fulbourn Road,Cambridge CB1 9NL,UK.

Objective: The current paper describes Diet In Nutrients Out (DINO), an integrated dietary assessment system incorporating dietary data entry and nutritional analysis within one platform for use in dietary assessment in small-scale intervention studies to national surveys.

Design: DINO contains >6000 food items, mostly aggregated composites of branded foods, across thirty-one main food groups divided into 151 subsidiary groups for detailed reporting requirements, with fifty-three core nutrient fields.

Setting: MRC Human Nutrition Research (HNR), Cambridge, UK and MRC Keneba, Gambia.

Subjects: DINO is used across dietary assessment projects at HNR and MRC Keneba.

Results: DINO contains macro- and micronutrients as well as additional variables of current research and policy interest, such as caffeine, whole grains, vitamin K and added sugars. Disaggregated data are available for fruit, vegetables, meat, fish and cheese in composite foods, enabling greater accuracy when reporting food consumption or assessing adherence to dietary recommendations. Portion sizes are categorised in metric and imperial weights, with standardised portion sizes for each age group. Regular reviews are undertaken for portion sizes and food composition to ensure contemporary relevance. A training programme and a checking schedule are adhered to for quality assurance purposes, covering users and data. Eating context questions are integrated to record where and with whom the respondent is eating, allowing examination between these factors and the foods consumed.

Conclusions: An up-to-date quality-assured system for dietary assessment is crucial for nutritional surveillance and research, but needs to have the flexibility to be tailored to address specific research questions.
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http://dx.doi.org/10.1017/S1368980014000342DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4862572PMC
February 2015

Identification and characterisation of eroA and ervA, encoding two putative thiol oxidases from Aspergillus niger.

Gene 2010 Aug 8;461(1-2):32-41. Epub 2010 May 8.

School of Biology, University of Nottingham, Nottingham, NG7 2RD, UK.

The oxidative folding of proteins in the secretory pathway involves the formation and isomerisation of disulphide bonds and is catalysed by foldases in the lumen of the endoplasmic reticulum (ER). The transfer of reducing equivalents, from disulphide bond formation, to oxygen involves the participation of thiol oxidases. Here, we describe the identification and functional characterisation of the eroA and ervA genes from Aspergillus niger, encoding functional orthologues of S. cerevisiae ERO1 and ERV2, respectively. The eroA gene encodes a product of 600 amino acids, EroA, and the ervA gene encodes a product of 215 amino acids, ErvA, both of which share common motifs and features with their S. cerevisiae orthologues. In contrast to Ero1p in S. cerevisiae, A. niger EroA appears to be retained in the ER lumen by a C-terminal retention motif. Real-time PCR analysis indicated that eroA is transcriptionally up-regulated in response to ER stress, whereas ervA is slightly down-regulated in response to DTT stress yet up-regulated in response to expression of a heterologous protein. Gene disruption studies indicated that, unlike ervA, eroA is essential for viability. When expressed in the thermosensitive S. cerevisiae ero1-1 strain, both eroA and ervA were able to complement the temperature and DTT sensitive phenotype, although a truncated eroA, missing the putative HEEL ER-retention signal was unable to complement as well as the full-length eroA gene.
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http://dx.doi.org/10.1016/j.gene.2010.04.011DOI Listing
August 2010

Epigenetic mechanisms silence a disintegrin and metalloprotease 33 expression in bronchial epithelial cells.

J Allergy Clin Immunol 2008 Jun 21;121(6):1393-9, 1399.e1-14. Epub 2008 Apr 21.

Brooke Laboratories, Division of Infection, Inflammation and Repair, School of Medicine, University of Southampton, Southampton, United Kingdom.

Background: A disintegrin and metalloprotease 33 (ADAM33) polymorphism is strongly associated with asthma and bronchial hyperresponsiveness. Although considered to be a mesenchymal cell-specific gene, recent reports have suggested epithelial expression of ADAM33 in patients with severe asthma.

Objectives: Because dysregulated expression of ADAM33 can contribute to disease pathogenesis, we characterized the mechanism or mechanisms that control its transcription and investigated ADAM33 expression in bronchial biopsy specimens and brushings from healthy and asthmatic subjects.

Methods: The ADAM33 promoter and CpG island methylation were analyzed by using bioinformatics, luciferase reporters, and bisulfite sequencing of genomic DNA. Epithelial-mesenchymal transition was induced by using TGF-beta1. ADAM33 mRNA was scrutinized in bronchial biopsy specimens and brushings by using reverse transcriptase-quantitative polymerase chain reaction, melt-curve analysis, and direct sequencing.

Results: The predicted ADAM33 promoter (-550 to +87) had promoter transcriptional activity. Bisulfite sequencing showed that the predicted promoter CpG island (-362 to +80) was hypermethylated in epithelial cells but hypomethylated in ADAM33-expressing fibroblasts. Treatment of epithelial cells with 5-aza-deoxycytidine caused demethylation of the CpG island and induced ADAM33 expression. In contrast, phenotypic transformation of epithelial cells through a TGF-beta-induced epithelial-mesenchymal transition was insufficient to induce ADAM33 expression. ADAM33 mRNA was confirmed in bronchial biopsy specimens, but no validated signal was detected in bronchial brushings from healthy or asthmatic subjects.

Conclusion: The ADAM33 gene contains a regulatory CpG island within its promoter, the methylation status of which tightly controls its expression in a cell type-specific manner. ADAM33 repression is a stable feature of airway epithelial cells, irrespective of disease.
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http://dx.doi.org/10.1016/j.jaci.2008.02.031DOI Listing
June 2008

The soluble form of a disintegrin and metalloprotease 33 promotes angiogenesis: implications for airway remodeling in asthma.

J Allergy Clin Immunol 2008 Jun 14;121(6):1400-6, 1406.e1-4. Epub 2008 Apr 14.

Division of Infection, Inflammation, and Repair, School of Medicine, Southampton General Hospital, University of Southampton, Southampton, United Kingdom.

Background: A disintegrin and metalloprotease (ADAM)-33 is a susceptibility gene for asthma and chronic obstructive pulmonary disease whose function remains unknown.

Objective: Because asthmatic bronchoalveolar lavage fluid contains high levels of soluble ADAM33 (sADAM33), which includes the catalytic domain, we postulated that its release from cell membranes might play functional roles in airway remodeling by promoting angiogenesis.

Methods: The proangiogenic activity of the highly purified catalytic domain of ADAM33 or a catalytically inactive mutant was studied in vitro (Matrigel assay), ex vivo (human embryonic/fetal lung explants) and in vivo (chorioallantoic membrane assay). The regulation of sADAM33 release from cells overexpressing full-length ADAM33 and its biological activity were characterized.

Results: We show that the purified catalytic domain of ADAM33, but not its inactive mutant, causes rapid induction of endothelial cell differentiation in vitro, and neovascularization ex vivo and in vivo. We also show that TGF-beta(2) enhances sADAM33 release from cells overexpressing full-length ADAM33 and that this truncated form is biologically active.

Conclusion: The discovery that sADAM33 promotes angiogenesis defines it as a tissue remodeling gene with potential to affect airflow obstruction and lung function independently of inflammation. As TGF-beta(2) enhances sADAM33 release, environmental factors that cause epithelial damage may synergize with ADAM33 in asthma pathogenesis, resulting in a disease-related gain of function. This highlights the potential for interplay between genetic and environmental factors in this complex disease.
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http://dx.doi.org/10.1016/j.jaci.2008.03.003DOI Listing
June 2008

Child-specific and family-wide risk factors using the retrospective Childhood Experience of Care & Abuse (CECA) instrument: a life-course study of adult chronic depression - 3.

J Affect Disord 2007 Nov 8;103(1-3):225-36. Epub 2007 Aug 8.

Department of Social Psychiatry Group, King's College London, St Thomas' Hospital Campus, Lambeth Palace Road, London, SE1 7EH, UK.

Background: An earlier paper [Brown, G.W., Craig, T.K.J., Harris, T.O., Handley, R.V., Harvey, A.L., 2007a-this issue. Development of a retrospective interview measure of parental maltreatment using the Childhood Experience of Care & Abuse (CECA) instrument - a life-course study of adult chronic depression - 1. J. Affect. Disord. doi:10.1016/j.jad.2007.05.022] documented an association between parental maltreatment and risk of adult chronic depression. This paper explores the contribution of other child-specific factors (e.g. conduct problems) and family-wide factors (e.g. parental discord).

Methods: Data are derived from an enquiry of 198 women largely comprising of adult sister pairs. Data was collected by semi-structured interviews covering a wide range of parental behaviour and childhood behaviour.

Results: Parental maltreatment emerged as channelling the effect of family-wide factors on risk of adult chronic depression, but with a child's conduct problems and shame-withdrawal partly mediating this link. A child's depression before 17, although correlated with parental maltreatment, did not appear to play a significant role in adult depression. This core model is supplemented by analyses exploring the mechanisms involved. A mother's rejection/physical abuse and her depression via her lax control, for example, account for the link of parental maltreatment with conduct problems. Also 'rebelliousness' of a child relates to the chances of her low affection moving to rejection. "Rebelliousness" also appears to play a role in why the paired sisters so often had a different experience of maltreatment.

Limitations: The data is collected retrospectively - but see [Brown, G.W., Craig, T.K.J., Harris, T.O., Handley, R.V., Harvey, A.L., 2007b-this issue. Validity of retrospective measures of early maltreatment and depressive episodes using the Childhood Experience of Care and Abuse (CECA) instrument - A life-course study of adult chronic depression - 2. J. Affect. Disord. doi:10.1016/j.jad.2007.06.003].

Conclusions: Child-specific factors play a major role in the origins of adult chronic depressive episodes. This, however, is fully consistent with an equally significant contribution from family-wide factors. The crucial point is that the link of the latter with such depression appears to be indirect and mediated very largely by parental maltreatment.
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http://dx.doi.org/10.1016/j.jad.2007.06.007DOI Listing
November 2007

Validity of retrospective measures of early maltreatment and depressive episodes using the Childhood Experience of Care and Abuse (CECA) instrument -- A life-course study of adult chronic depression - 2.

J Affect Disord 2007 Nov 25;103(1-3):217-24. Epub 2007 Jul 25.

Department of Social Psychiatry Group, King's College London, St Thomas' Hospital Campus, Lambeth Palace Road, London, SE1 7EH, UK.

Background: A previous paper, using data collected retrospectively from sister pairs, reported substantial associations of adult depressive episodes lasting at least 12 months with childhood maltreatment [Brown, G.W., Craig, T.K.J., Harris, T.O. Handley, R.V. & Harvey, A.L. 2007a-this issue. Development of a retrospective interview measure of parental maltreatment using the Childhood Experience of Care & Abuse (CECA) instrument - a life-course study of adult chronic depression - 1. J. Affect. Disord. doi:10.1016/j.jad.2007.05.022]. Risk was far less when depressive episodes of any duration were considered. This paper considers how much scientific weight can be placed on these findings in the light of doubt often expressed about retrospective collection of childhood and adult data.

Methods: The retrospectively gathered material was obtained from adult sister pairs within 5 years of age, comprising a high-risk series (n = 118) where the first sister was selected as likely to have experienced childhood abuse or neglect, and a comparison series (n = 80) where she was selected at random. Current age ranged between early 20s and 50s. Data was collected by semi-structured interviews, using investigator-based ratings covering a wide range of parental behaviour and childhood behaviour.

Results: A series of analyses failed to reveal evidence of significant bias in the collection of material about adult depression or parental maltreatment. There was, however, some evidence of under reporting.

Limitations: Conclusions from such analyses can only be judged in terms of degree of plausibility.

Conclusions: Nothing emerged to suggest the presence of significant bias in the aetiological findings of our earlier paper. There is evidence of some underreporting of both early adverse experience and adult depressive episodes, but this is unlikely to threaten the conclusions drawn about the link of parental maltreatment with adult chronic depressive episodes.
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http://dx.doi.org/10.1016/j.jad.2007.06.003DOI Listing
November 2007

Development of a retrospective interview measure of parental maltreatment using the Childhood Experience of Care and Abuse (CECA) instrument -- A life-course study of adult chronic depression - 1.

J Affect Disord 2007 Nov 24;103(1-3):205-15. Epub 2007 Jul 24.

Department of Social Psychiatry Group, King's College London, St Thomas' Hospital Campus, Lambeth Palace Road, London, SE1 7EH, UK.

Background: Childhood maltreatment among women is related to risk of adult depression and particularly an episode taking a chronic course. This paper explores the aspects of parental behaviour involved.

Methods: An expanded version of CECA (Childhood Experiences of Care and Abuse), a retrospective interview-based instrument covering neglect as well as various forms of abuse is used to develop a new index of parental maltreatment. Data are derived from an enquiry of sister pairs between early 20s and 50s, comprising a high-risk series (n=118) where the first sister was selected as likely to have experienced childhood abuse or neglect, and a comparison series (n=80) where she was selected at random.

Results: Adverse maternal behaviour emerges as of critical importance for the link with adult chronic depression. Maternal lack of affection ('neglect') and maternal rejection ('emotional abuse') form the core of an index of parental maltreatment, and it is concluded that persistent rejection, particularly from a mother, appears to be the core experience of importance. The findings of behavioural genetics that the experience of siblings of parents in ordinary families often differs have been found to hold for the more extreme behaviour involved in maltreatment. Difference between siblings in risk of later chronic depression is entirely related to such experience.

Limitations: The study is based on retrospective questioning of adult women. Our next paper considers the possible threats to validity involved [Brown, G.W., Craig, T.K.J., Harris, T.O., Handley, R.V., Harvey, A.L., 2007a. Validity of retrospective measures of early maltreatment and depressive episodes using CECA (Childhood Experience of Care and Abuse) - a life-course study of adult chronic depression - 2. J. Affect. Disord. doi:10.1016/j.jad.2007.06.003].

Conclusions: Parental maltreatment emerges as a critical determinant of later chronic depressive episodes among adult women.
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http://dx.doi.org/10.1016/j.jad.2007.05.022DOI Listing
November 2007

Sorption of chlorhexidine on cellulose: mechanism of binding and molecular recognition.

J Phys Chem B 2007 Aug 29;111(30):8775-84. Epub 2007 Jun 29.

Green Chemistry Group, Centre for Technical Textiles, University of Leeds, Leeds, LS2 9JT, United Kingdom.

Chlorhexidine (CH) is an effective antimicrobial agent. There has been very little work published concerning the interactions of CH with, and its adsorption mechanism on, cellulose. In this paper, such physical chemistry parameters are examined and related to computational chemistry studies. Adsorption isotherms were constructed following application of CH to cellulose. These were typical of a Langmuir adsorption isotherm, but at higher concentrations displayed good correlation also with a Freundlich isotherm. Sorption was attributed to a combination of electrostatic (major contribution) and hydrogen bonding forces, which endorsed computational chemistry proposals: electrostatic interactions between CH and carboxylic acid groups in the cellulose dominate with a contribution to binding through hydrogen bonding of the biguanide residues and the p-chlorophenol moieties (Yoshida H-bonding) with the cellulose hydroxyl groups. At high CH concentrations, there is evidence of monolayer and bilayer aggregation. Differences in sorption between CH and another antimicrobial agent previously studied, poly(hexamethylenebiguanide) (PHMB), are attributed to higher molecular weight of PHMB and higher charge density of biguanide residues in CH (due to the relative electron withdrawing effect of the p-chlorophenol moiety).
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http://dx.doi.org/10.1021/jp070856rDOI Listing
August 2007

Sorption of poly(hexamethylenebiguanide) on cellulose: mechanism of binding and molecular recognition.

Langmuir 2006 Jun;22(13):5636-44

Green Chemistry Group, Centre for Technical Textiles, University of Leeds, Leeds, LS2 9JT, UK.

Antimicrobial agents such as poly(hexamethylene biguanide) (PHMB) find application in medical, apparel, and household textile sectors; although it is understood that certain concentrations need to be applied to achieve suitable performance, there has been very little work published concerning the interactions of the polymer and its adsorption mechanism on cellulose. In this paper, such physical chemistry parameters are examined and related to computational chemistry studies. Adsorption isotherms were constructed: at low concentrations, these were typical Langmuir isotherms; at higher concentrations, they were more indicative of Freundlich isotherms, attributed to a combination of electrostatic and hydrogen-bonding forces, which endorsed computational chemistry proposals. At lower concentrations, electrostatic interactions between PHMB and carboxylic acid groups in the cellulose dominate with a contribution to binding through hydrogen bonding; as the concentration of PHMB increases, hydrogen bonding with cellulose becomes increasingly dominant. At high PHMB concentrations, observations of increasing PHMB adsorption are attributed to monolayer aggregation and multilayer stacking of PHMB through electrostatic interactions with counterions and hydrogen bonding of biguanide groups.
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http://dx.doi.org/10.1021/la053002bDOI Listing
June 2006