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Das S, Pandey AK, Morris DE, Anderson R, Lim V, Wie CC, Yap IKS, Alattraqchi AG, Simin H, Abdullah R, Yeo CC, Clarke SC, Cleary DW. Respiratory carriage of hypervirulent Klebsiella pneumoniae by indigenous populations of Malaysia. BMC Genomics 2024; 25:381. [PMID: 38632538 PMCID: PMC11025145 DOI: 10.1186/s12864-024-10276-4] [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: 10/03/2023] [Accepted: 04/01/2024] [Indexed: 04/19/2024] Open
Abstract
Klebsiella pneumoniae is a Gram-negative Enterobacteriaceae that is classified by the World Health Organisation (WHO) as a Priority One ESKAPE pathogen. South and Southeast Asian countries are regions where both healthcare associated infections (HAI) and community acquired infections (CAI) due to extended-spectrum β-lactamase (ESBL)-producing and carbapenem-resistant K. pneumoniae (CRKp) are of concern. As K. pneumoniae can also exist as a harmless commensal, the spread of resistance genotypes requires epidemiological vigilance. However there has been no significant study of carriage isolates from healthy individuals, particularly in Southeast Asia, and specially Malaysia. Here we describe the genomic analysis of respiratory isolates of K. pneumoniae obtained from Orang Ulu and Orang Asli communities in Malaysian Borneo and Peninsular Malaysia respectively. The majority of isolates were K. pneumoniae species complex (KpSC) 1 K. pneumoniae (n = 53, 89.8%). Four Klebsiella variicola subsp. variicola (KpSC3) and two Klebsiella quasipneumoniae subsp. similipneumoniae (KpSC4) were also found. It was discovered that 30.2% (n = 16) of the KpSC1 isolates were ST23, 11.3% (n = 6) were of ST65, 7.5% (n = 4) were ST13, and 13.2% (n = 7) were ST86. Only eight of the KpSC1 isolates encoded ESBL, but importantly not carbapenemase. Thirteen of the KpSC1 isolates carried yersiniabactin, colibactin and aerobactin, all of which harboured the rmpADC locus and are therefore characterised as hypervirulent. Co-carriage of multiple strains was minimal. In conclusion, most isolates were KpSC1, ST23, one of the most common sequence types and previously found in cases of K. pneumoniae infection. A proportion were hypervirulent (hvKp) however antibiotic resistance was low.
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Affiliation(s)
- Souradeep Das
- Faculty of Medicine, Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Anish K Pandey
- Faculty of Medicine, Institute for Life Sciences, University of Southampton, Southampton, UK
- NIHR Southampton Biomedical Research Centre, University Hospital Southampton Foundation NHS Trust, Southampton, UK
| | - Denise E Morris
- Faculty of Medicine, Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Rebecca Anderson
- Faculty of Medicine, Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Victor Lim
- School of Medicine, International Medical University, Kuala Lumpur, Malaysia
| | - Chong Chun Wie
- Institute for Research, Development and Innovation, International Medical University, Kuala Lumpur, Malaysia
- School of Pharmacy, Monash University Malaysia, Bandar Sunway, Selangor, Malaysia
| | - Ivan Kok Seng Yap
- School of Pharmacy, Monash University Malaysia, Bandar Sunway, Selangor, Malaysia
| | - Ahmed Ghazi Alattraqchi
- Centre for Research in Infectious Diseases and Biotechnology (CeRIDB), Faculty of Medicine, Universiti Sultan Zainal Abidin, Medical Campus, 20400, Kuala Terengganu, Terengganu, Malaysia
| | - Hafis Simin
- Faculty of Applied Social Sciences, Universiti Sultan Zainal Abidin, Gong Badak Campus, 21300, Kuala Nerus, Terengganu, Malaysia
| | - Ramle Abdullah
- Centre of Excellence in National Indigenous Pedagogy, Institute of Teacher Education Tengku, Ampuan Afzan Campus, Pahang, Malaysia
| | - Chew Chieng Yeo
- Centre for Research in Infectious Diseases and Biotechnology (CeRIDB), Faculty of Medicine, Universiti Sultan Zainal Abidin, Medical Campus, 20400, Kuala Terengganu, Terengganu, Malaysia
| | - Stuart C Clarke
- Faculty of Medicine, Institute for Life Sciences, University of Southampton, Southampton, UK
- NIHR Southampton Biomedical Research Centre, University Hospital Southampton Foundation NHS Trust, Southampton, UK
- Institute for Research, Development and Innovation, International Medical University, Kuala Lumpur, Malaysia
- Global Health Research Institute, University of Southampton, Southampton, UK
| | - David W Cleary
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, University of Birmingham, UK.
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Abstract
Moraxella catarrhalis is a common cause of respiratory tract infection, particularly otitis media in children, whilst it is also associated with the onset of exacerbation in chronic obstructive pulmonary disease in adults. Despite the need for an efficacious vaccine against M. catarrhalis, no candidates have progressed to clinical trial. This study, therefore, aimed to characterize the diversity of M. catarrhalis isolated from the upper respiratory tract of healthy children and adults, to gain a better understanding of the epidemiology of M. catarrhalis and the distribution of genes associated with virulence factors, to aid vaccine efforts. Isolates were sequenced and the presence of target genes reported. Contrary to prevailing data, this study found that lipooligosaccharide (LOS) B serotypes are not exclusively associated with 16S type 1. In addition, a particularly low prevalence of LOS B and high prevalence of LOS C serotypes was observed. M. catarrhalis isolates showed low prevalence of antimicrobial resistance and a high gene prevalence for a number of the target genes investigated: ompB2 (also known as copB), ompCD, ompE, ompG1a, ompG1b, mid (also known as hag), mcaP, m35, tbpA, lbpA, tbpB, lbpB, msp22, msp75 and msp78, afeA, pilA, pilQ, pilT, mod, oppA, sbp2, mcmA and mclS.
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Affiliation(s)
- Denise E Morris
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - Karen L Osman
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - David W Cleary
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, UK.,Global Health Research Institute, University of Southampton, Southampton SO17 1BJ, UK.,NIHR Southampton Biomedical Research Centre, University Hospital Southampton Foundation NHS Trust, Southampton SO16 6YD, UK
| | - Stuart C Clarke
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, UK.,Global Health Research Institute, University of Southampton, Southampton SO17 1BJ, UK.,NIHR Southampton Biomedical Research Centre, University Hospital Southampton Foundation NHS Trust, Southampton SO16 6YD, UK
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Cleary DW, Devine VT, Morris DE, Osman KL, Gladstone RA, Bentley SD, Faust SN, Clarke SC. Corrigendum: Pneumococcal vaccine impacts on the population genomics of non-typeable Haemophilus influenzae. Microb Genom 2021; 7:000559. [PMID: 33945458 PMCID: PMC8209729 DOI: 10.1099/mgen.0.000559] [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] [Received: 03/15/2021] [Indexed: 11/18/2022] Open
Affiliation(s)
- David W. Cleary
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
- NIHR Southampton Biomedical Research Centre, University Hospital Southampton Foundation NHS Trust, Southampton, UK
| | - Vanessa T. Devine
- Northern Ireland Centre for Stratified Medicine and Clinical Translational Research Innovation Centre, Londonderry, UK
| | - Denise E. Morris
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Karen L. Osman
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | | | | | - Saul N. Faust
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
- NIHR Southampton Clinical Research Facility, University Hospital Southampton Foundation NHS Trust, Southampton, UK
| | - Stuart C. Clarke
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
- NIHR Southampton Biomedical Research Centre, University Hospital Southampton Foundation NHS Trust, Southampton, UK
- Global Health Research Institute, University of Southampton, Southampton, UK
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Morris DE, McNeil H, Hocknell RE, Anderson R, Tuck AC, Tricarico S, Norazmi MN, Lim V, Siang TC, Lim PKC, Wie CC, Cleary DW, Yap IKS, Clarke SC. Carriage of upper respiratory tract pathogens in rural communities of Sarawak, Malaysian Borneo. Pneumonia (Nathan) 2021; 13:6. [PMID: 33894778 PMCID: PMC8070298 DOI: 10.1186/s41479-021-00084-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [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] [Received: 12/18/2020] [Accepted: 03/22/2021] [Indexed: 11/10/2022] Open
Abstract
Introduction Pneumonia is a leading cause of death in Malaysia. Whilst many studies have reported the aetiology of pneumonia in Western countries, the epidemiology of pneumonia in Malaysia remains poorly understood. As carriage is a prerequisite for disease, we sought to improve our understanding of the carriage and antimicrobial resistance (AMR) of respiratory tract pathogens in Malaysia. The rural communities of Sarawak are an understudied part of the Malaysian population and were the focus of this study, allowing us to gain a better understanding of bacterial epidemiology in this population. Methods A population-based survey of bacterial carriage was undertaken in participants of all ages from rural communities in Sarawak, Malaysia. Nasopharyngeal, nasal, mouth and oropharyngeal swabs were taken. Bacteria were isolated from each swab and identified by culture-based methods and antimicrobial susceptibility testing conducted by disk diffusion or E test. Results 140 participants were recruited from five rural communities. Klebsiella pneumoniae was most commonly isolated from participants (30.0%), followed by Staphylococcus aureus (20.7%), Streptococcus pneumoniae (10.7%), Haemophilus influenzae (9.3%), Moraxella catarrhalis (6.4%), Pseudomonas aeruginosa (6.4%) and Neisseria meningitidis (5.0%). Of the 21 S. pneumoniae isolated, 33.3 and 14.3% were serotypes included in the 13 valent PCV (PCV13) and 10 valent PCV (PCV10) respectively. 33.8% of all species were resistant to at least one antibiotic, however all bacterial species except S. pneumoniae were susceptible to at least one type of antibiotic. Conclusion To our knowledge, this is the first bacterial carriage study undertaken in East Malaysia. We provide valuable and timely data regarding the epidemiology and AMR of respiratory pathogens commonly associated with pneumonia. Further surveillance in Malaysia is necessary to monitor changes in the carriage prevalence of upper respiratory tract pathogens and the emergence of AMR, particularly as PCV is added to the National Immunisation Programme (NIP). Supplementary Information The online version contains supplementary material available at 10.1186/s41479-021-00084-9.
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Affiliation(s)
- Denise E Morris
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Hannah McNeil
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Rebecca E Hocknell
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Rebecca Anderson
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Andrew C Tuck
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Serena Tricarico
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Mohd Nor Norazmi
- School of Health Sciences, Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia
| | - Victor Lim
- School of Medicine, International Medical University, Kuala Lumpur, Malaysia
| | - Tan Cheng Siang
- Faculty of Medicine and Health Sciences, Universiti Malaysia Sarawak, Kota Samarahan, Sarawak, Malaysia
| | - Patricia Kim Chooi Lim
- School of Medicine, International Medical University, Kuala Lumpur, Malaysia.,Institute for Research, Development and Innovation, International Medical University, Kuala Lumpur, Malaysia
| | - Chong Chun Wie
- Institute for Research, Development and Innovation, International Medical University, Kuala Lumpur, Malaysia.,School of Pharmacy, Monash University Malaysia, Bandar Sunway, Selangor, Malaysia
| | - David W Cleary
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK.,NIHR Southampton Biomedical Research Centre, University Hospital Southampton Foundation NHS Trust, Southampton, UK
| | - Ivan Kok Seng Yap
- Institute for Research, Development and Innovation, International Medical University, Kuala Lumpur, Malaysia.,Sarawak Research and Development Council, Kuching, Sarawak, Malaysia
| | - Stuart C Clarke
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK. .,Institute for Research, Development and Innovation, International Medical University, Kuala Lumpur, Malaysia. .,NIHR Southampton Biomedical Research Centre, University Hospital Southampton Foundation NHS Trust, Southampton, UK. .,Global Health Research Institute, University of Southampton, Southampton, UK.
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5
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Cleary DW, Morris DE, Anderson RA, Jones J, Alattraqchi AG, A Rahman NI, Ismail S, Razali MS, Mohd Amin R, Abd Aziz A, Esa NK, Amiruddin S, Chew CH, Simin H, Abdullah R, Yeo CC, Clarke SC. The upper respiratory tract microbiome of indigenous Orang Asli in north-eastern Peninsular Malaysia. NPJ Biofilms Microbiomes 2021; 7:1. [PMID: 33402693 PMCID: PMC7785749 DOI: 10.1038/s41522-020-00173-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 11/24/2020] [Indexed: 12/19/2022] Open
Abstract
Much microbiome research has focused on populations that are predominantly of European descent, and from narrow demographics that do not capture the socio-economic and lifestyle differences which impact human health. Here we examined the airway microbiomes of the Orang Asli, the indigenous peoples of Malaysia. A total of 130 participants were recruited from two sites in the north-eastern state of Terengganu in Peninsular Malaysia. Using 16S rRNA sequencing, the nasal microbiome was significantly more diverse in those aged 5-17 years compared to 50+ years (p = 0.023) and clustered by age (PERMANOVA analysis of the Bray-Curtis distance, p = 0.001). Hierarchical clustering of Bray-Curtis dissimilarity scores revealed six microbiome clusters. The largest cluster (n = 28; 35.4%) had a marked abundance of Corynebacterium. In the oral microbiomes Streptococcus, Neisseria and Haemophilus were dominant. Using conventional microbiology, high levels of Staphylococcus aureus carriage were observed, particularly in the 18-65 age group (n = 17/36; 47.2% 95% CI: 30.9-63.5). The highest carriage of pneumococci was in the <5 and 5 to 17 year olds, with 57.1% (4/7) and 49.2% (30/61), respectively. Sixteen pneumococcal serotypes were identified, the most common being the nonvaccine-type 23A (14.6%) and the vaccine-type 6B (9.8%). The prevalence of pneumococcal serotypes covered by pneumococcal conjugate vaccines support introduction into a Malaysian national immunisation schedule. In addition, the dominance of Corynebacterium in the airway microbiomes is intriguing given their role as a potentially protective commensal with respect to acute infection and respiratory health.
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Affiliation(s)
- David W Cleary
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK.
- NIHR Southampton Biomedical Research Centre, University Hospital Southampton NHS Trust, Southampton, UK.
| | - Denise E Morris
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Rebecca A Anderson
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Jessica Jones
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Ahmed Ghazi Alattraqchi
- Faculty of Medicine, Universiti Sultan Zainal Abidin, Medical Campus, 20400, Kuala Terengganu, Terengganu, Malaysia
| | - Nor Iza A Rahman
- Faculty of Medicine, Universiti Sultan Zainal Abidin, Medical Campus, 20400, Kuala Terengganu, Terengganu, Malaysia
| | - Salwani Ismail
- Faculty of Medicine, Universiti Sultan Zainal Abidin, Medical Campus, 20400, Kuala Terengganu, Terengganu, Malaysia
| | - Mohd Sayuti Razali
- Faculty of Medicine, Universiti Sultan Zainal Abidin, Medical Campus, 20400, Kuala Terengganu, Terengganu, Malaysia
| | - Rahmah Mohd Amin
- Faculty of Medicine, Universiti Sultan Zainal Abidin, Medical Campus, 20400, Kuala Terengganu, Terengganu, Malaysia
| | - Aniza Abd Aziz
- Faculty of Medicine, Universiti Sultan Zainal Abidin, Medical Campus, 20400, Kuala Terengganu, Terengganu, Malaysia
| | - Nor Kamaruzaman Esa
- Faculty of Medicine, Universiti Sultan Zainal Abidin, Medical Campus, 20400, Kuala Terengganu, Terengganu, Malaysia
| | - Salman Amiruddin
- Faculty of Medicine, Universiti Sultan Zainal Abidin, Medical Campus, 20400, Kuala Terengganu, Terengganu, Malaysia
| | - Ching Hoong Chew
- Faculty of Health Sciences, Universiti Sultan Zainal Abidin, Gong Badak Campus, 21300, Kuala Nerus, Terengganu, Malaysia
| | - Hafis Simin
- Faculty of Applied Social Sciences, Universiti Sultan Zainal Abidin, Gong Badak Campus, 21300, Kuala Nerus, Terengganu, Malaysia
- Akademi Seni Budaya dan Warisan Kebangsaan, (ASWARA), Jalan Tun Ismail, Kuala Lumpur, Malaysia
| | - Ramle Abdullah
- Faculty of Applied Social Sciences, Universiti Sultan Zainal Abidin, Gong Badak Campus, 21300, Kuala Nerus, Terengganu, Malaysia
| | - Chew Chieng Yeo
- Faculty of Medicine, Universiti Sultan Zainal Abidin, Medical Campus, 20400, Kuala Terengganu, Terengganu, Malaysia
| | - Stuart C Clarke
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
- NIHR Southampton Biomedical Research Centre, University Hospital Southampton NHS Trust, Southampton, UK
- Global Health Research Institute, University of Southampton, Southampton, UK
- School of Postgraduate Studies, International Medical University, Kuala Lumpur, Malaysia
- Centre for Translational Research, IMU Institute for Research, Development and Innovation (IRDI), Kuala Lumpur, Malaysia
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Cleary DW, Devine VT, Morris DE, Osman KL, Gladstone RA, Bentley SD, Faust SN, Clarke SC. Pneumococcal vaccine impacts on the population genomics of non-typeable Haemophilus influenzae. Microb Genom 2018; 4. [PMID: 30080135 PMCID: PMC6202451 DOI: 10.1099/mgen.0.000209] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [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: 11/18/2022] Open
Abstract
The implementation of pneumococcal conjugate vaccines (PCVs) has led to a decline in vaccine-type disease. However, there is evidence that the epidemiology of non-typeable Haemophilus influenzae (NTHi) carriage and disease can be altered as a consequence of PCV introduction. We explored the epidemiological shifts in NTHi carriage using whole genome sequencing over a 5-year period that included PCV13 replacement of PCV7 in the UK’s National Immunization Programme in 2010. Between 2008/09 and 2012/13 (October to March), nasopharyngeal swabs were taken from children <5 years of age. Significantly increased carriage post-PCV13 was observed and lineage-specific associations with Streptococcus pneumoniae were seen before but not after PCV13 introduction. NTHi were characterized into 11 discrete, temporally stable lineages, congruent with current knowledge regarding the clonality of NTHi. The increased carriage could not be linked to the expansion of a particular clone and different co-carriage dynamics were seen before PCV13 implementation when NTHi co-carried with vaccine serotype pneumococci. In summary, PCV13 introduction has been shown to have an indirect effect on NTHi epidemiology and there exists both negative and positive, distinct associations between pneumococci and NTHi. This should be considered when evaluating the impacts of pneumococcal vaccine design and policy.
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Affiliation(s)
- David W Cleary
- 1Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK.,2NIHR Southampton Biomedical Research Centre, University Hospital Southampton Foundation NHS Trust, Southampton, UK
| | - Vanessa T Devine
- 3Northern Ireland Centre for Stratified Medicine and Clinical Translational Research Innovation Centre, Londonderry, UK
| | - Denise E Morris
- 1Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Karen L Osman
- 1Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | | | | | - Saul N Faust
- 1Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK.,5NIHR Southampton Clinical Research Facility, University Hospital Southampton Foundation NHS Trust, Southampton, UK
| | - Stuart C Clarke
- 2NIHR Southampton Biomedical Research Centre, University Hospital Southampton Foundation NHS Trust, Southampton, UK.,1Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK.,6Global Health Research Institute, University of Southampton, Southampton, UK
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7
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Coughtrie AL, Morris DE, Anderson R, Begum N, Cleary DW, Faust SN, Jefferies JM, Kraaijeveld AR, Moore MV, Mullee MA, Roderick PJ, Tuck A, Whittaker RN, Yuen HM, Doncaster CP, Clarke SC. Ecology and diversity in upper respiratory tract microbial population structures from a cross-sectional community swabbing study. J Med Microbiol 2018; 67:1096-1108. [PMID: 29927372 DOI: 10.1099/jmm.0.000773] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
PURPOSE Respiratory tract infections (RTIs) are responsible for over 2.8 million deaths per year worldwide with pathobiont carriage a required precursor to infection. We sought to determine carriage epidemiology for both bacterial and viral respiratory pathogens as part of a large population-based cross-sectional carriage study. METHODOLOGY Nose self-swab samples were collected in two separate time-points, May to August 2012 (late spring/summer) and February to April 2013 (winter/early spring). The presence of six bacterial species: S. pneumoniae, H. influenzae, M. catarrhalis, S. aureus, P. aeruginosa and N. meningitidis in addition to respiratory syncytial virus, influenza viruses A and B, rhinovirus/enterovirus, coronavirus, parainfluenza viruses 1-3 and adenovirus was determined using culture and PCR methods.Results/Key findings. Carriage was shown to vary with age, recent RTI and the presence of other species. Spatial structures of microbial communities were more disordered in the 0-4 age group and those with recent RTI. Species frequency distributions were flatter than random expectation in young individuals (X2=20.42, P=0.002), indicating spatial clumping of species consistent with facilitative relationships. Deviations from a neutral model of ecological niches were observed in summer samples and from older individuals but not in the winter or younger individuals (0-4 years), suggesting the presence of seasonal and age-dependent niche processes in respiratory community assembly. CONCLUSION The application of epidemiological methods and ecological theory to respiratory tract samples has yielded novel insights into the factors that drive microbial community composition.
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Affiliation(s)
- Abigail L Coughtrie
- 1Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Denise E Morris
- 1Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Rebecca Anderson
- 1Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Nelupha Begum
- 1Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | - David W Cleary
- 1Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK.,2NIHR Southampton Biomedical Research Centre, University Hospital Southampton Foundation NHS Trust, Southampton, UK
| | - Saul N Faust
- 1Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK.,3NIHR Southampton Clinical Research Facility, University Hospital Southampton Foundation NHS Trust, Southampton, UK.,4NIHR Southampton Respiratory Biomedical Research Unit, University Hospital Southampton Foundation NHS Trust, Southampton, UK
| | - Johanna M Jefferies
- 1Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK.,4NIHR Southampton Respiratory Biomedical Research Unit, University Hospital Southampton Foundation NHS Trust, Southampton, UK
| | - Alex R Kraaijeveld
- 5Centre for Biological Sciences, University of Southampton, Southampton, UK
| | - Michael V Moore
- 1Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Mark A Mullee
- 1Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK.,6NIHR Research Design Service South Central, University Hospital Southampton Foundation NHS Trust, Southampton, UK
| | - Paul J Roderick
- 1Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK.,7Global Health Research Institute, University of Southampton, Southampton, UK
| | - Andrew Tuck
- 1Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Robert N Whittaker
- 1Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Ho Ming Yuen
- 1Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | - C Patrick Doncaster
- 5Centre for Biological Sciences, University of Southampton, Southampton, UK
| | - Stuart C Clarke
- 7Global Health Research Institute, University of Southampton, Southampton, UK.,2NIHR Southampton Biomedical Research Centre, University Hospital Southampton Foundation NHS Trust, Southampton, UK.,1Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK.,4NIHR Southampton Respiratory Biomedical Research Unit, University Hospital Southampton Foundation NHS Trust, Southampton, UK
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Erickson KA, Kagan BD, Scott BL, Morris DE, Kiplinger JL. Revisiting the bis(dimethylamido) metallocene complexes of thorium and uranium: improved syntheses, structure, spectroscopy, and redox energetics of (C 5Me 5) 2An(NMe 2) 2 (An = Th, U). Dalton Trans 2018; 46:11208-11213. [PMID: 28795722 DOI: 10.1039/c7dt02373a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reaction of (C5Me5)2AnCl2 (An = Th, U) with 2.8 or 4 equivalents of LiNMe2, respectively, affords (C5Me5)2An(NMe2)2 in high yields. In addition to improved syntheses, the solid-state structures, voltammetric data, and UV-visible-NIR spectra for these classic actinide bis(dimethylamido) complexes are presented for the first time.
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Affiliation(s)
- K A Erickson
- Chemistry Division, Los Alamos National Laboratory, Mail Stop J514, Los Alamos, NM 87545, USA.
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Abstract
Lower and upper respiratory infections are the fourth highest cause of global mortality (Lozano et al., 2012). Epidemic and pandemic outbreaks of respiratory infection are a major medical concern, often causing considerable disease and a high death toll, typically over a relatively short period of time. Influenza is a major cause of epidemic and pandemic infection. Bacterial co/secondary infection further increases morbidity and mortality of influenza infection, with Streptococcus pneumoniae, Haemophilus influenzae, and Staphylococcus aureus reported as the most common causes. With increased antibiotic resistance and vaccine evasion it is important to monitor the epidemiology of pathogens in circulation to inform clinical treatment and development, particularly in the setting of an influenza epidemic/pandemic.
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Affiliation(s)
- Denise E. Morris
- Infectious Disease Epidemiology Group, Academic Unit of Clinical and Experimental Sciences, Faculty of Medicine, Institute for Life Sciences, University of Southampton, University Hospital Southampton Foundation NHS TrustSouthampton, United Kingdom
| | - David W. Cleary
- Infectious Disease Epidemiology Group, Academic Unit of Clinical and Experimental Sciences, Faculty of Medicine, Institute for Life Sciences, University of Southampton, University Hospital Southampton Foundation NHS TrustSouthampton, United Kingdom
| | - Stuart C. Clarke
- Infectious Disease Epidemiology Group, Academic Unit of Clinical and Experimental Sciences, Faculty of Medicine, Institute for Life Sciences, University of Southampton, University Hospital Southampton Foundation NHS TrustSouthampton, United Kingdom
- Global Health Research Institute, University of SouthamptonSouthampton, United Kingdom
- NIHR Southampton Respiratory Biomedical Research UnitSouthampton, United Kingdom
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10
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Devine VT, Cleary DW, Jefferies JMC, Anderson R, Morris DE, Tuck AC, Gladstone RA, O'Doherty G, Kuruparan P, Bentley SD, Faust SN, Clarke SC. The rise and fall of pneumococcal serotypes carried in the PCV era. Vaccine 2017; 35:1293-1298. [PMID: 28161425 DOI: 10.1016/j.vaccine.2017.01.035] [Citation(s) in RCA: 51] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Revised: 01/09/2017] [Accepted: 01/17/2017] [Indexed: 11/30/2022]
Abstract
Streptococcus pneumoniae is a major cause of meningitis, sepsis and pneumonia worldwide. Vaccination using pneumococcal conjugate vaccines (PCV) has therefore been part of the UK's childhood immunisation programme since 2006. Here we describe pneumococcal carriage rates in children under five years of age attending the paediatric department of a large UK hospital in response to vaccine implementation over seven winter seasons from 2006 to 2013. S. pneumoniae (n=696) were isolated from nasopharyngeal swabs (n=2267) collected during seven consecutive winters, October to March, 2006/7 to 2012/13. This includes the period immediately following the introduction of the seven-valent pneumococcal conjugate vaccine (PCV7) in 2006 in addition to pre- and post-PCV13 introduction in 2010. We show a decrease in PCV13 vaccine serotypes (VT) in the three years following PCV13 vaccine implementation (2010/11 to 2012/13). Serotype 6A represented the only observed VT following PCV13 implementation with all others (including PCV7 serotypes) absent from carriage. Overall pneumococcal carriage, attributable to non-VT (NVT), was consistent across all sampling years with a mean of 31·1%. The ten most frequently isolated NVTs were 6C, 11A, 15B, 23B, 15A, 21, 22F, 35F, 23A and 15C. Fluctuations in the prevalence of each were however noted. Comparing prevalence at 2006/07 with 2012/13 only 15A was shown to have increased significantly (p value of 0·003) during the course of PCV implementation. These data support the increasing evidence that the primary effect of PCVs is due to population immunity by reducing or eliminating the carriage of invasive VT serotypes. With IPD being increasingly attributed to non-vaccine serotypes, surveillance of carriage data continues to act as an early warning system for vaccine design and public health policy that require continual data of both carried pneumococcal serotypes and IPD attributed serotype data.
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Affiliation(s)
- Vanessa T Devine
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - David W Cleary
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - Johanna M C Jefferies
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, UK; Southampton NIHR Respiratory Biomedical Research Unit, University Hospital Southampton Foundation NHS Trust, Southampton SO16 6YD, UK
| | - Rebecca Anderson
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - Denise E Morris
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - Andrew C Tuck
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - Rebecca A Gladstone
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, UK; Pathogen Genomics, Wellcome Trust Sanger Institute, Hinxton CB10 1SA, UK
| | - Grace O'Doherty
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - Priyasharmila Kuruparan
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - Stephen D Bentley
- Pathogen Genomics, Wellcome Trust Sanger Institute, Hinxton CB10 1SA, UK
| | - Saul N Faust
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, UK; Southampton NIHR Respiratory Biomedical Research Unit, University Hospital Southampton Foundation NHS Trust, Southampton SO16 6YD, UK; NIHR Wellcome Trust Clinical Research Facility, University Hospital Southampton Foundation NHS Trust, Southampton SO16 6YD, UK
| | - Stuart C Clarke
- Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, UK; Southampton NIHR Respiratory Biomedical Research Unit, University Hospital Southampton Foundation NHS Trust, Southampton SO16 6YD, UK.
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11
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Abstract
Capillary refill time (CRT) is a simple means of cardiovascular assessment which is widely used in clinical care. Currently, CRT is measured through manual assessment of the time taken for skin tone to return to normal colour following blanching of the skin surface. There is evidence to suggest that manually assessed CRT is subject to bias from ambient light conditions, a lack of standardisation of both blanching time and manually applied pressure, subjectiveness of return to normal colour, and variability in the manual assessment of time. We present a novel automated system for CRT measurement, incorporating three components: a non-invasive adhesive sensor incorporating a pneumatic actuator, a diffuse multi-wavelength reflectance measurement device, and a temperature sensor; a battery operated datalogger unit containing a self contained pneumatic supply; and PC based data analysis software for the extraction of refill time, patient skin surface temperature, and sensor signal quality. Through standardisation of the test, it is hoped that some of the shortcomings of manual CRT can be overcome. In addition, an automated system will facilitate easier integration of CRT into electronic record keeping and clinical monitoring or scoring systems, as well as reducing demands on clinicians. Summary analysis of volunteer (n = 30) automated CRT datasets are presented, from 15 healthy adults and 15 healthy children (aged from 5 to 15 years), as their arms were cooled from ambient temperature to 5°C. A more detailed analysis of two typical datasets is also presented, demonstrating that the response of automated CRT to cooling matches that of previously published studies.
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Affiliation(s)
- L L Blaxter
- Electrical Systems & Optics Research Division, Faculty of Engineering, University of Nottingham, University Park, Nottingham NG7 2RD, UK
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12
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Abstract
Management of advanced-stage uterine serous carcinoma (USC) is uncertain, and postsurgical therapeutic options swing between radiation and chemotherapy. The aim of this study is to evaluate the utility of radiotherapy compared to platinum-based chemotherapy in women with advanced-stage USC. We retrospectively identified cases of USC at our institution. Survival distributions were calculated by the Kaplan-Meier method. Two-tailed t-tests were used to compare time to progression and time to death. We identified 24 women diagnosed with either stage III or IV USC. Time to progression for women receiving radiotherapy was 5.3 months as compared with 12.4 months for women receiving chemotherapy (P = 0.01). Mean time to death for the radiotherapy group was 8 months compared to 18 months in the chemotherapy group (P = 0.04). Kaplan-Meier survival curves were significantly different between the two groups (P = 0.01). While radiotherapy appears to control USC recurrences in the pelvis, the disease often recurs distantly. When compared to radiotherapy, platinum-based chemotherapy appears to increase disease-free survival and time to death in women with advanced-stage USC.
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Affiliation(s)
- P A Gehrig
- Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
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13
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Chisholm-Brause CJ, Berg JM, Little KM, Matzner RA, Morris DE. Uranyl sorption by smectites: spectroscopic assessment of thermodynamic modeling. J Colloid Interface Sci 2004; 277:366-82. [PMID: 15341848 DOI: 10.1016/j.jcis.2004.04.047] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2004] [Accepted: 04/23/2004] [Indexed: 10/26/2022]
Abstract
Batch sorption experiments and thermodynamic modeling of the interaction of UO2(2+) and its hydrolysis products with two smectitic clay minerals, the reference material SWy-1 [McKinley et al., Clays Clay Miner. 43 (1995) 586] and the soil isolate LK-1 [Turner et al., Geochim. Cosmochim. Acta 30 (1996) 3399], have established a conceptual framework for uranyl/smectite surface complexation based on general reactions between aqueous uranyl species and the reactive sites on the mineral surfaces. In this report, we have formulated and spectroscopically tested a set of hypotheses based on this conceptual framework using samples prepared under similar or identical conditions to evaluate the agreement between surface complexation/speciation as enumerated by spectroscopic characterization and that elaborated by the surface complexation model. Both steady-state and time-resolved optical emission spectral data are presented for uranyl on both smectite minerals as well as on the analogue phases SiO2 and Al(OH)3 spanning the pH range from approximately 4 to 8 and the background electrolyte concentrations from approximately 0.001 to 0.1 M. The spectral data enable the explicit identification of an outer-sphere exchange-site population of the hydrated cation [UO2(OH2)5(2+) ] in SWy-1. Spectral data also clearly establish the existence of inner-sphere surface complexes on the analogue phases and on the amphoteric clay crystallite edge sites [aluminol (>Al-OH) and silanol (>Si-OH)]. Based on the spectral characteristics of these uranyl edge-site populations, it is possible to readily infer for the SiO2, Al(OH)3, and SWy-1 samples the evolution in surface speciation with increasing pH to more hydrolyzed uranyl-surface complexes consistent with the conceptual model. The spectral domain characteristics of the edge-site populations on LK-1 with increasing pH suggest that there is no change in the hydrolysis of the uranyl-surface species. However, emission lifetime data are interpreted as indicating a shift in the surface speciation of the same uranyl-surface species from aluminol sites to silanol sites with pH increase. This observation is also consistent with the conceptual framework of the model. Data are also reported for Eu3+/smectite samples to provide additional insight into the exchange site populations. The emission spectra for Eu3+ in the basal-plane exchange sites differs significantly between SWy-1 and LK-1 samples reflecting a difference in the basal plane spacing between these two minerals, but the emission lifetime data suggest that the Eu3+ cation remains fully hydrated in both systems. The overall general description of surface speciation of uranyl on these mineral phases as enumerated by spectroscopy is in good accord with that derived from the conceptual thermodynamic model, lending added confidence to our understanding and descriptions of surface complexation behavior in this complex geochemical system.
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Affiliation(s)
- C J Chisholm-Brause
- Department of Applied Science, College of William and Mary, Applied Research Center, 12050 Jefferson Avenue, Newport News, VA 23606, USA.
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14
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Abstract
Metastatic tumors to the brain are an increasing cause of morbidity and mortality in patients with systemic cancers. Many new therapies used to treat systemic cancers do not penetrate the central nervous system (CNS) and do not protect patients from the development of brain metastases. Surgery, radiosurgery, and radiation therapy are all used to treat brain metastases. It is in our opinion a mistake to use only one or two of these modalities to the exclusion of other(s). The role of systemic chemotherapy is still limited, due to both the issues of drug delivery caused by the blood brain barrier and to the relative resistance of many of these tumors to chemotherapy. Traditionally, brain metastases have been grouped together regardless of the origin of the tumor and have been treated with a single algorithm. As we encounter more patients for whom treatment of the brain metastases is an important determinant of survival, we must tailor our treatment strategies to individual tumor types. Also, we must recognize differences in each tumor's sensitivity to chemotherapy and radiotherapy and differences in their biology.
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Affiliation(s)
- M G Ewend
- Division of Neurosurgery, University of North Carolina at Chapel Hill, 148 Burnett-Womack Building, Campus Box 7060, Chapel Hill, NC 27599-7060, USA.
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15
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Duval PB, Burns CJ, Buschmann WE, Clark DL, Morris DE, Scott BL. Reaction of the uranyl(VI) ion (UO(2)(2+)) with a triamidoamine ligand: preparation and structural characterization of a mixed-valent uranium(V/VI) oxo-imido dimer. Inorg Chem 2001; 40:5491-6. [PMID: 11599946 DOI: 10.1021/ic010155n] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The synthesis and structural characterization of a mixed-valent uranium(V/VI) oxo-imido complex are reported. Reaction of the uranyl chloride complex [K(18-crown-6)](2)[UO(2)Cl(4)] (1) with the triamidoamine ligand Li(3)[N(CH(2)CH(2)NSiBu(t)Me(2))(3)] yields oxo-imido [K(18-crown-6)(Et(2)O)][UO(mu(2)-NuCH(2)CH(2)N(CH(2)CH(2)NSiBu(t)Me(2))(2))](2) (2) as the major isolated uranium product in moderate yield. The reaction that forms 2 involves activation of both the triamidoamine ligand and the uranyl dioxo unit of 1. An X-ray crystal structure determination of 2 reveals a dimeric complex in which the coordination geometry at each uranium center is that of a capped trigonal bipyramid. The multidentate triamidoamine ligand coordinates to uranium through the capping amine and two of the three pendant amido ligands, while the third pendant amido donor has been activated to generate a bridging imido ligand by loss of the silyl substituent. One of the uranyl oxo groups is retained as a terminal ligand to complete the coordination sphere for each uranium center. The oxo and imido nitrogen may be regarded as the axial ligands of the trigonal bipyramid, while the two amido ligands and the other imido donor occupy equatorial coordination sites. The central amine of the tripodal set serves as the capping ligand. Distortion of the axial O-U-N angle from 180 degrees emanates from the proximity of the capping amine and the bridging interaction to the other uranium center. The structure and bonding in 2 are assessed in the context of metal-ligand multiple bonding in high-valent actinide complexes. The possibility of valence averaging [5.5/5.5 vs 5.0/6.0] via delocalization or rapid intramolecular electron-transfer dynamics of the unpaired electron is also discussed in the context of crystallographic, spectroscopic (NMR, IR, Raman, and EPR), and electrochemical data. Crystal data for 2: triclinic space group P1 macro, a = 12.1144(6) A, b = 12.6084(6) A, c = 14.5072(7) A, alpha = 101.374(1) degrees, beta = 103.757(1) degrees, gamma = 109.340(1) degrees, z = 1, R1 = 0.0523, wR2 = 0.1359.
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Affiliation(s)
- P B Duval
- Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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16
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Morris DE, Bourland JD, Rosenman JG, Shaw EG. Three-dimensional conformal radiation treatment planning and delivery for low- and intermediate-grade gliomas. Semin Radiat Oncol 2001; 11:124-37. [PMID: 11285550 DOI: 10.1053/srao.2001.22060] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Three-Dimensional conformal radiation treatment (3D-CRT) planning and delivery is an external beam radiation therapy modality that has the general goal of conforming the shape of a prescribed dose volume to the shape of a 3-dimensional target volume, simultaneously limiting dose to critical normal structures. 3-Dimensional conformal therapy should include at least one volumetric imaging study of the patient. This image should be obtained in the treatment position for visualizing the target and normal anatomic structures that are potentially within the irradiated volume. Most often, computed tomography (CT) and/or magnetic resonance imaging (MRI) are used; however, recently, other imaging modalities such as functional MRI, MR spectroscopy, and positron emission tomography (PET) scans have been used to visualize the clinically relevant volumes. This article will address the clinically relevant issues with regard to low- and intermediate-grade gliomas and the role of 3D-CRT planning. Specific issues that will be addressed will include normal tissue tolerance, target definition, treatment field design in regard to isodose curves and dose-volume histograms, and immobilization.
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Affiliation(s)
- D E Morris
- Department of Radiation Oncology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7512, USA.
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17
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Abstract
Acquired methemoglobinemia occurs rarely in clinical practice. We present a case of a 57-year-old man who developed severe drug-induced methemoglobinemia after exposure to benzocaine spray and lidocaine jelly during intubation for an elective thoracoscopic lung biopsy. Information regarding the classifications, pathophysiology, diagnosis, and treatment of this entity is reviewed.
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Affiliation(s)
- D R Lorelli
- Department of General Surgery, Henry Ford Hospital, Detroit, Michigan 48202, USA
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18
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Chisholm-Brause CJ, Berg JM, Matzner RA, Morris DE. Uranium(VI) Sorption Complexes on Montmorillonite as a Function of Solution Chemistry. J Colloid Interface Sci 2001; 233:38-49. [PMID: 11112304 DOI: 10.1006/jcis.2000.7227] [Citation(s) in RCA: 128] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have investigated the effect of changes in solution chemistry on the nature of uranyl sorption complexes on montmorillonite (SAz-1) at different surface coverages (1.43-53.6 µmol/g). Uranyl uptake onto SAz-1 between pH 3 and 7 was determined in both titration and batch-mode experiments. These pH values result in solutions that contain a range of monomeric and oligomeric aqueous uranyl species. Continuous-wave and time-resolved emission spectroscopies were used to investigate the nature of U(VI) sorbed to SAz-1. A discrete set of uranyl surface complexes has been identified over a wide range of pH values at these low to moderate coverages. For all samples, two surface complexes are detected with spectral characteristics commensurate with an inner-sphere complex and an exchange-site complex; the relative abundance of these two species is similar over these pH values at low coverage (1.43-2.00 µmol/g). In addition, surface species having spectra consistent with polymeric hydroxide-like sorption complexes form at the moderate coverages ( approximately 34-54 µmol/g), increasing in abundance as the capacity of the amphoteric surface sites is exceeded. Furthermore, a species with spectral characteristics anticipated for an outer-sphere surface complex is observed for wet paste samples at low pH (3.7-4.4) and both low ( approximately 2 µmol/g) and moderate ( approximately 40 µmol/g) coverage. There are only subtle differences in the nature of sorption complexes formed at different pH values but similar coverages, despite markedly different uranyl speciation in solution. These results indicate that the speciation in the solution has minimal influence on the nature of the sorption complex under these experimental conditions. The primary control on the nature and abundance of the different uranyl sorption complexes appears to be the relative abundance and reactivity of the different sorption sites. Copyright 2001 Academic Press.
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Affiliation(s)
- CJ Chisholm-Brause
- School of Marine Science, College of William and Mary, VIMS, Gloucester Point, Virginia, 23062
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19
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Wilkerson MP, Burns CJ, Dewey HJ, Martin JM, Morris DE, Paine RT, Scott BL. Basicity of uranyl oxo ligands upon coordination of alkoxides. Inorg Chem 2000; 39:5277-85. [PMID: 11154586 DOI: 10.1021/ic000142u] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Uranium(VI) alkoxide complexes are prepared via metathesis reactions of [UO2Cl2(THF)2]2 with potassium alkoxides in nonaqueous media. The dark red compound U[OCH2C(CH3)3]6, 1, results from redistributive exchange of oxo and neopentoxide ligands between more than one uranium species. Single-crystal X-ray diffraction analysis of 1 reveals a monomer in which the uranium is coordinated in a pseudooctahedral fashion by six neopentoxide ligands. Imposition of steric congestion at the metal center prevents oxo-alkoxide ligand exchange in the reactions using more sterically demanding alkoxides. Simple metathesis between uranyl chloride and alkoxide ligands occurs in the synthesis of golden yellow-orange UO2(OCHPh2)2(THF)2, 2, and yellow UO2[OCH(tBu)Ph]2(THF)2, 3. Single-crystal X-ray diffraction analysis of 2 reveals a monomer in which the uranium is coordinated in a pseudooctahedral fashion by two apical oxo ligands, two diphenylmethoxide ligands occupying trans positions, and two tetrahydrofuran ligands. Coordination of diisopropylmethoxide allows for synthesis of a more complex binary alkoxide system. Single-crystal X-ray diffraction analysis of watermelon red [UO2(OCH(iPr)2)2]4, 4, reveals a tetramer in which each uranium is coordinated in a pseudooctahedral fashion by two apical oxo ligands, one terminal alkoxide, two bridging alkoxide ligands, and one bridging oxo ligand from a neighboring uranyl group. These compounds are characterized by elemental analysis, 1H NMR, infrared spectroscopy, and, for 1, 2, and 4, single-crystal X-ray diffraction analysis. Luminescence spectroscopy is employed to evaluate the extent of aggregation of compounds 2-4 in various solvents. Vibrational spectroscopic measurements of 2-4 imply that, in contrast to the case of uranyl complexes prepared in aqueous environments, coordination of relatively strongly donating alkoxide ligands allows for enhancement of electron density on the uranyl groups such that the uranyl U=O bonds are weakened. Crystal data are as follows. 1: monoclinic space group C2/m, a = 10.6192(8) A, b = 18.36(1) A, c = 10.6151(8) A, beta = 109.637(1) degrees, V = 1949.1(3) A3, Z = 2, dcalc = 1.297 g cm-3. Refinement of 2065 reflections gave R1 = 0.045. 2: monoclinic space group P2(1)/c, a = 6.1796(4) A, b = 15.669(1) A, c = 16.169(1) A, beta = 95.380(1) degrees, V = 1558.7(2) A3, Z = 2, dcalc = 1.664 g cm-3. Refinement of 3048 reflections gave R1 = 0.036. 4: tetragonal space group I4, a = 17.8570(6) A, b = 17.8570(6) A, c = 11.4489(6) A, V = 3650.7(3) A3, Z = 2, dcalc = 1.821 g cm-3. Refinement of 1981 reflections gave R1 = 0.020.
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Affiliation(s)
- M P Wilkerson
- Chemical Science and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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20
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Abstract
Every radiation oncologist is faced occasionally with the need to consider reirradiation for palliation. Because reirradiation has the potential to exceed normal tissue tolerances, there is a need to have information on the efficacy and toxicity of retreatment. This article reviews the reirradiation literature and provides guidance to clinicians with regard to the risks, benefits, and side effects of retreatment.
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Affiliation(s)
- D E Morris
- Department of Radiation Oncology, the University of North Carolina, Chapel Hill, NC, USA
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21
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22
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Abstract
Excessive scarring in the form of keloids and hypertrophic scars continues to be a clinical problem for some patients. The lack of an animal model for such scarring has been an obstacle to studying the cellular and molecular biology of these entities. Previous observations made by the authors that some surgical scars in the rabbit ear remain raised for months after wounding prompted us to investigate whether the rabbit ear might provide a model by which to study excessive dermal scarring. After establishing the model in preliminary study, 40 excisional wounds, 6 mm in diameter, were created over the ventral surface of rabbit ears. Elevated scars were treated with either intralesional triamcinolone acetonide or saline at day 16 postwounding. On day 22, 25 scar wounds were used for thorough histomorphometric analysis, 15 wounds were eliminated prior to analysis because of invagination of epithelial tissue, which made analysis difficult. Total area of scar and Hypertrophic Index, a ratio comparing scar prominence with the thickness of adjacent unwounded tissue, were measured for 25 (62 percent) of the resulting scars. Both total area of scar and Hypertrophic Index were found to be significantly decreased in the steroid-treated group (p < 0.02 and < 0.03, respectively). In a chronic form of this model, in which larger excisions were taken, an excessive accumulation of both new collagen and cartilage over 9 months was observed. An animal model for excessive dermal scarring that allows quantitation of scar formation and, at an early stage, can be modulated in a predictable way with intralesional corticosteroid treatment is presented. This model may parallel hypertrophic scarring in humans and thus might provide a tool by which to study its pathophysiology and objectively evaluate therapeutic modalities.
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Affiliation(s)
- D E Morris
- Department of Surgery, Northwestern University Hospital Medical School, Chicago, Ill., USA
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Wu L, Siddiqui A, Morris DE, Cox DA, Roth SI, Mustoe TA. Transforming growth factor beta 3 (TGF beta 3) accelerates wound healing without alteration of scar prominence. Histologic and competitive reverse-transcription-polymerase chain reaction studies. Arch Surg 1997; 132:753-60. [PMID: 9230861 DOI: 10.1001/archsurg.1997.01430310067014] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Transforming growth factor (TGF) beta 3 is a new isoform of the TGF beta superfamily and is presumed to play an important role in wound repair and scarring. OBJECTIVE To examine the effects of TGF beta 3 on wound healing and on reducing scarring. DESIGN AND INTERVENTIONS Dermal ulcers were created on the ears of 75 anesthetized young female rabbits. Either TGF beta 3 or vehicle was applied topically to the wounds. Wounds were bisected and analyzed histologically at postwounding day 7. A second group of wounds was treated with topical TGF beta 3 and TGF beta 2 or vehicle at days 0 and 3 and harvested at days 21 through 42 as an excessive scarring model. The third group of wounds was treated with TGF beta 1, TGF beta 2, and TGF beta 3 and vehicle. The granulation tissue was harvested at day 7, and cellular RNA was extracted for performing competitive reverse-transcription polymerase chain reaction. MAIN OUTCOME MEASUREMENT The amount of new epithelium and granulation tissue was measured in TGF beta 3- and vehicle-treated wounds. The hypertrophic index was calculated for scarring wounds treated with TGF beta 2 and TGF beta 3 or vehicle. Levels of TGF beta 1 messenger RNA were measured in those wounds that were treated with TGF beta 1, TGF beta 2, and TGF beta 3 and in their controls. RESULTS The use of TGF beta 3 (0.3-0.75 microgram per wound) increased granulation tissue formation by more than 100% (P < .005). Epithelialization showed a biphase, either increasing 30% (P < .04) or decreasing 25% (P < .001) dependent on dose. No significant difference in the hypertrophic index was noted in TGF beta 3-treated wounds compared with controls. Levels of TGF beta 1 messenger RNA increased (7.1- to 14.9-fold) in those wounds treated with TGF beta s compared with controls at day 7. CONCLUSIONS Exogenous TGF beta 3 displays substantial vulnerary properties in wound healing and may be useful in treating nonhealing wounds. However, the observation that TGF beta 3 can reduce scarring was not confirmed in this study, and the messenger RNA level in response to TGF beta 3 suggests that it behaves similarly to TGF beta 1.
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Affiliation(s)
- L Wu
- Division of Plastic and Reconstructive Surgery, Northwestern University Medical School, Chicago, Ill, USA
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24
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Zhao G, Kirtikar V, Singh KK, Sinha AP, Morris DE, Inyushkin AV. Large copper isotope effect in oxygen depleted YBa2Cu3Oy: Importance of Cu-dominated phonon modes in the pairing mechanism. Phys Rev B Condens Matter 1996; 54:14956-14959. [PMID: 9985545 DOI: 10.1103/physrevb.54.14956] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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25
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Zhao G, Ager JW, Morris DE. Site dependence of large oxygen isotope effect in Y0.7Pr0.3Ba2Cu3O6.97. Phys Rev B Condens Matter 1996; 54:14982-14985. [PMID: 9985552 DOI: 10.1103/physrevb.54.14982] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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26
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Zhao G, Morris DE. Reply to "Comment on 'Observation of a possible oxygen isotope effect on the effective mass of carriers in YBa2Cu3O6.94' ". Phys Rev B Condens Matter 1996; 54:15545-15546. [PMID: 9985626 DOI: 10.1103/physrevb.54.15545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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27
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Wegerer R, Thomsen C, Cardona M, Bornemann HJ, Morris DE. Raman investigation of YBa2-xLaxCu3O7 ceramics. Phys Rev B Condens Matter 1996; 53:3561-3565. [PMID: 9983871 DOI: 10.1103/physrevb.53.3561] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Zhao G, Singh KK, Sinha AP, Morris DE. Oxygen isotope effect on the effective mass of carriers from magnetic measurements on La2-xSrxCuO4. Phys Rev B Condens Matter 1995; 52:6840-6844. [PMID: 9981913 DOI: 10.1103/physrevb.52.6840] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Zhao G, Morris DE. Observation of a possible oxygen isotope effect on the effective mass of carriers in YBa2Cu3O6.94. Phys Rev B Condens Matter 1995; 51:16487-16490. [PMID: 9978650 DOI: 10.1103/physrevb.51.16487] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Morris DE. A PAPER THAT CHANGED MY PRACTICE. West J Med 1995. [DOI: 10.1136/bmj.310.6989.1244] [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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Zhao G, Morris DE. Composition dependence of the oxygen isotope effect in Ba1-xKxBiO3: Evidence for oxygen-mass dependence of the coupling constant. Phys Rev B Condens Matter 1995; 51:12848-12851. [PMID: 9978070 DOI: 10.1103/physrevb.51.12848] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Zhao G, Morris DE. Sizable oxygen isotope effects in the electron-doped Pr1.85Ce0.15CuO4-y. Phys Rev B Condens Matter 1994; 50:3454-3457. [PMID: 9976610 DOI: 10.1103/physrevb.50.3454] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Zhao G, Singh KK, Morris DE. Oxygen isotope effect on Néel temperature in various antiferromagnetic cuprates. Phys Rev B Condens Matter 1994; 50:4112-4117. [PMID: 9976694 DOI: 10.1103/physrevb.50.4112] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Nickel JH, Morris DE, Ager JW. Nickel, Morris, and Ager reply. Phys Rev Lett 1994; 72:1389. [PMID: 10056701 DOI: 10.1103/physrevlett.72.1389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Bornemann HJ, Morris DE, Sinha AP, Chandrachood MR, Liu HB. Modification of the oxygen-isotope effect in high-temperature superconductors due to transition-metal doping. Phys Rev B Condens Matter 1993; 48:9803-9809. [PMID: 10007231 DOI: 10.1103/physrevb.48.9803] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Nickel JH, Morris DE, Ager JW. Locus of pairing interaction in YBa2Cu3O7 by site-selective oxygen isotope shift: 18O in CuO2 plane layers. Phys Rev Lett 1993; 70:81-84. [PMID: 10053263 DOI: 10.1103/physrevlett.70.81] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Iqbal Z, Baughman RH, Khare S, Murthy NS, Ramakrishna BL, Bornemann HJ, Morris DE. Superconducting Transition Temperature of Doped C60: Retraction. Science 1992; 256:950-1. [PMID: 17794983 DOI: 10.1126/science.256.5059.950-a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Zhang H, Lynn JW, Morris DE. Coupled-bilayer two-dimensional magnetic order of the Dy ions in Dy2Ba4Cu7O15. Phys Rev B Condens Matter 1992; 45:10022-10031. [PMID: 10000891 DOI: 10.1103/physrevb.45.10022] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Liu HB, Morris DE, Sinha AP. Tc enhancement versus rare-earth size in R0.9Ca0.1Ba2Cu4O8 (R=Sm, Eu, Gd, Dy, Ho, and Er). Phys Rev B Condens Matter 1992; 45:2438-2441. [PMID: 10001767 DOI: 10.1103/physrevb.45.2438] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Bornemann HJ, Morris DE, Steinleitner C, Czjzek G. Magnetic order and local structural aspects involving Gd in GdBa2Cu4O8. Phys Rev B Condens Matter 1991; 44:12567-12570. [PMID: 9999419 DOI: 10.1103/physrevb.44.12567] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Iqbal Z, Baughman RH, Ramakrishna BL, Khare S, Murthy NS, Bornemann HJ, Morris DE. Superconductivity at 45 K in Rb/Tl Codoped C60 and C60/C70 Mixtures. Science 1991; 254:826-9. [PMID: 17787170 DOI: 10.1126/science.254.5033.826] [Citation(s) in RCA: 91] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The appearance of superconductivity at relatively high temperatures in alkali metal-doped C(60) fullerene provides the challenge to both understand the nature and origin of the superconductivity and to determine the upper limit of the superconducting transition temperature (T(c)). Towards the latter goal, it is shown that doping with potassium-thallium and rubidium-thallium alloys in the 400 to 430 degrees C temperature range increases the T(c) of C(60)/C(70) mixtures to 25.6 K and above 45 K, respectively. Similar increases in T(c) were also observed upon analogous doping of pure C(60). Partial substitution of potassium with thallium in interstitial sites between C(60) molecules is suggested by larger observed unit cell parameters than for the K(3)C(60) and K(4)C(60) phases. Contrary to previous results for C(60) doped with different alkali metals, such expansion does not alone account for the changes in critical temperature.
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Morris DE, Markelz AG, Wei JY, Hultgren CT, Nickel JH, Hamilton JC, McCarty KF. Site-selective oxygen-isotope substitution in YBa2Cu3O7- delta. Phys Rev B Condens Matter 1991; 44:9556-9561. [PMID: 9998941 DOI: 10.1103/physrevb.44.9556] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Bornemann HJ, Morris DE. Isotope effect in YBa2-xLaxCu3Oz: Evidence for phonon-mediated high-temperature superconductivity. Phys Rev B Condens Matter 1991; 44:5322-5325. [PMID: 9998349 DOI: 10.1103/physrevb.44.5322] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Liu HB, Morris DE. Eight rare-earth-substituted Pb-based 1:2:1:2 superconducting compounds: (Pb,Cu)Sr2(Ca,R)Cu2O7 (R=Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm). Phys Rev B Condens Matter 1991; 44:5369-5372. [PMID: 9998362 DOI: 10.1103/physrevb.44.5369] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Tang XX, Morris DE. 77-K superconductor Pb0.8SrBa1.2Y0.7Ca0.3Cu3O7+ delta : Comparison with other Pb-based superconductors. Phys Rev B Condens Matter 1991; 44:4553-4559. [PMID: 10000110 DOI: 10.1103/physrevb.44.4553] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Tang XX, Morris DE, Sinha AP. Superconductivity at 67 K in (Pb,Cu)Sr2(Ca,Y)Cu2O7 by precise adjustment of oxygen. Phys Rev B Condens Matter 1991; 43:7936-7941. [PMID: 9996415 DOI: 10.1103/physrevb.43.7936] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Zhang H, Lynn JW, Li WH, Clinton TW, Morris DE. Two- and three-dimensional magnetic order of the rare-earth ions in RBa2Cu4O8. Phys Rev B Condens Matter 1990; 41:11229-11236. [PMID: 9993543 DOI: 10.1103/physrevb.41.11229] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Morris DE, Narwankar P, Sinha AP, Takano K, Fayn B, Shum VT. Calcium-substituted Y-Ba-Cu-O superconductors with enhanced Tc synthesized at elevated oxygen pressures. Phys Rev B Condens Matter 1990; 41:4118-4122. [PMID: 9994234 DOI: 10.1103/physrevb.41.4118] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Morris DE, Asmar NG, Wei JY, Nickel JH, Sid RL, Scott JS, Post JE. Synthesis and properties of the 2:4:7 superconductors R2Ba4Cu7O15-x (R=Y,Eu,Gd,Dy,Ho,Er). Phys Rev B Condens Matter 1989; 40:11406-11409. [PMID: 9991730 DOI: 10.1103/physrevb.40.11406] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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