81 results on '"P. J. Vallely"'
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2. Exploring the association between multidimensional poverty and antenatal care utilization in two provinces of Papua New Guinea: a cross-sectional study
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Olga P. M. Saweri, William S. Pomat, Andrew J. Vallely, Virginia Wiseman, Neha Batura, and For the WANTAIM Study Group
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Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background Although global poverty rates have declined in the last decade, the fall in the Asia-Pacific region has been slow relative to the rest of the world. Poverty continues to be a major cause of poor maternal and newborn health, and a barrier to accessing timely antenatal care. Papua New Guinea has one of the highest poverty rates and some of the worst maternal and neonatal outcomes in the Asia-Pacific region. Few studies have investigated equity in antenatal care utilization in this setting. We explored equity in antenatal care utilization and the determinants of service utilization, which include a measure of multidimensional poverty in Papua New Guinea. Methods To explore the association between poverty and antenatal care utilization this study uses data from a ten-cluster randomized controlled trial. The poverty headcount, average poverty gap, adjusted poverty headcount, and multidimensional poverty index of antenatal clinic attendees are derived using the Alkire-Foster method. The distribution of service utilization is explored using the multidimensional poverty index, followed by multivariate regression analyses to evaluate the determinants of service utilization. Results The poverty headcount was 61.06%, the average poverty gap 47.71%, the adjusted poverty headcount 29.13% and the average multidimensional poverty index was 0.363. Further, antenatal care utilization was regressive with respect to poverty. The regression analyses indicated that older women; being a widow (small number of widows (n = 3) asserts interpreting result with caution); or formally employed increase the likelihood of accessing antenatal care more often in pregnancy. Travelling for over an hour to receive care was negatively associated with utilization. Conclusion This study indicated high levels of multidimensional poverty in PNG and that ANC utilization was regressive; highlighting the need to encourage pregnant women, especially those who are economically more vulnerable to visit clinics regularly throughout pregnancy.
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- 2024
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3. Acceptability of self-collected vaginal swabs and point-of-care testing for sexually transmitted and genital infections among pregnant women in Papua New Guinea
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Lisa M. Vallely, Priscilla Poga, Michaela A. Riddell, Handan Wand, Alice Mengi, Steven G. Badman, John Bolnga, Delly Babona, William S. Pomat, Somu Nosi, Andrew J. Vallely, and Angela Kelly-Hanku
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Sexually transmitted infections ,Point-of -care test and treat ,Acceptability ,Pregnancy ,Papua New Guinea ,SDG 3: Good health and well-being ,Public aspects of medicine ,RA1-1270 - Abstract
The self-collection of vaginal swabs and point-of-care testing and treatment of sexually transmitted infections (STIs) is reported from several low-and middle-income countries. However, the reporting on women’s experiences of self-collection and same-day testing and treatment of STIs is less well described. In this paper, we present the acceptability of self-collected vaginal swabs and point-of-care testing and treatment among pregnant women enrolled in a clinical trial (Women and Newborn Trial of Antenatal Intervention and Management – WANTAIM) in Papua New Guinea. Semi-structured interviews were conducted among 54 women enrolled into WANTAIM to identify the acceptability of the test and treat approach. Analysis of qualitative data used deductive and inductive thematic analysis applying Sekhon, Cartwright and Francis’ acceptability theoretical framework. Most women reported that they understood that the vaginal swab was to identify infections that may affect their unborn baby; however, some were unsure about the specific infections they were being tested for. Among women who tested positive for an STI, some were unsure what they had been treated for. Overall, the self-collection of vaginal swabs for STI testing during pregnancy was highly acceptable.
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- 2024
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4. DNA methylation at individual CpG-sites of EPB41L3, HTERT and FAM19A4 are useful for detection of cervical high-grade squamous intraepithelial lesions (HSIL) or worse: Analysis of individual CpG-sites outperforms averaging
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Monica Molano, Dorothy A. Machalek, Samuel Phillips, Grace Tan, Suzanne M. Garland, David Hawkes, Prisha Balgovind, Reza Haqshenas, Steve G. Badman, John Bolnga, Josephine Gabuzzi, Zure Kombati, Gloria M. Munnull, Julia ML. Brotherton, Marion Saville, John M. Kaldor, Pamela J. Toliman, Andrew J. Vallely, and Gerald L. Murray
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DNA methylation ,Cervical cancer ,Human papillomavirus ,Diagnostic test ,Epigenetics ,Molecular diagnostics ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Global methylation analysis of gene promoters is promising for detection of high-grade squamous intraepithelial lesions or worse (HSIL+) in high-risk human papillomavirus (hrHPV)-positive women. However, diagnostic performance of methylation data at individual CpG-sites is limited. We explored methylation for predicting HSIL+ in self- and clinician-collected samples from Papua New Guinea.Methylation of EPB41L3 (1–6 CpG-sites), hTERT (1–10 CpG-sites) and FAM19A4 (1–5 CpG-sites) was assessed through pyrosequencing from 44 HPV+ samples (4 cancers, 19 HSIL, 4 low-grade squamous intraepithelial lesions (LSIL), 17 normal). New primers were designed for FAM19A4 directed to the first exon region not explored previously.In clinician-collected samples, methylation at CpG-sites 4 and 5 of EPB41L3 were the best HSIL predictors (AUC >0.83) and CpG-site 4 for cancer (0.925). Combination of EPB41L3 sites 2/4 plus FAM19A4 site 1 were the best HSIL+ markers [100% sensitivity, 63.2% specificity].Methylation at CpG-site 5 of FAM19A4 was the best HSIL predictor (0.67) in self-collected samples, and CpG-sites 1 and 3 of FAM19A4 for cancer (0.77). Combined, FAM19A4 site 1 plus HPV 16/18 detection yielded sensitivity of 82.6% and specificity of 61.9%.In conclusion, methylation at individual CpG-sites of EPB41L3 and FAM19A4 outperformed global analysis and improved HSIL+ detection, warranting further investigation.
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- 2024
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5. The prioritisation of curable sexually transmitted infections among pregnant women in Zambia and Papua New Guinea: Qualitative insights.
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Lisa M Vallely, Kelvin Kapungu, Alice Mengi, Mike Chaponda, R Matthew Chico, Michaela A Riddell, Andrew J Vallely, William Pomat, Eva Cignacco, Nicola Low, and Angela Kelly-Hanku
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Public aspects of medicine ,RA1-1270 - Abstract
Curable sexually transmitted infections (STIs) are neglected in public health policy, services and society at large. Effective interventions are available for some STI but seem not to be prioritised at global, regional or local levels. Zambia and Papua New Guinea (PNG) have a high burden of STIs among pregnant women but little is known about the prioritisation of STI treatment and care among this group. We undertook a qualitative study to explore how STIs are prioritised among pregnant women in local health systems in Zambia and PNG. Semi-structured interviews were conducted with 19 key informants-health care workers providing antenatal care, and policy and programme advisers across the two countries. Audio recordings were transcribed and translated into English and stored, managed, and coded in NVivo v12. Analysis used deductive and inductive thematic analysis. Findings were coded against the World Health Organization health system building blocks. Participants spoke about the stigma of STIs at the community level. They described a broad understanding of morbidity associated with undiagnosed and untreated STIs in pregnant women. The importance of testing and treating STIs in pregnancy was well recognised but many spoke of constraints in providing these services due to stock outs of test kits for HIV and syphilis and antibiotics. In both settings, syndromic management remains the mainstay for treating curable STIs. Clinical practice and treatment were not in alignment with current STI guidelines in either country, with participants recognising the need for mentorship and in-service training, as well as the availability of commodities to support their clinical practice. Local disruptions to screening and management of syphilis, HIV and other curable STIs were widely reported in both countries. There is a need to galvanise priority at national and regional levels to ensure ongoing access to supplies needed to undertake STI testing and treatment.
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- 2024
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6. Sexual and reproductive health needs and practices of female sex workers in Papua New Guinea: findings from a biobehavioral survey Kauntim mi tu (‘Count me too’)
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Damian Weikum, Angela Kelly-Hanku, Ruthy Neo-Boli, Herick Aeno, Steven G. Badman, Lisa M. Vallely, Barne Willie, Martha Kupul, Parker Hou, Angelyn Amos, Rebecca Narokobi, Simon Pekon, Kelsey Coy, Johanna Wapling, Janet Gare, John M. Kaldor, Andrew J. Vallely, Avi J. Hakim, and on behalf of the Kauntim mi tu Study Team
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Papua New Guinea ,Female sex workers ,Sexual and reproductive health ,HIV ,Antenatal care ,Moderately or highly effective contraception ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background Little research has explored the sexual and reproductive health (SRH) experience of female sex workers (FSW), including girls aged
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- 2022
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7. B-assembler: a circular bacterial genome assembler
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Fengyuan Huang, Li Xiao, Min Gao, Ethan J. Vallely, Kevin Dybvig, T. Prescott Atkinson, Ken B. Waites, and Zechen Chong
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Bacteria genome ,De novo assembly ,Long-read-only assembly ,Hybrid-read assembly ,Biotechnology ,TP248.13-248.65 ,Genetics ,QH426-470 - Abstract
Abstract Background Accurate bacteria genome de novo assembly is fundamental to understand the evolution and pathogenesis of new bacteria species. The advent and popularity of Third-Generation Sequencing (TGS) enables assembly of bacteria genomes at an unprecedented speed. However, most current TGS assemblers were specifically designed for human or other species that do not have a circular genome. Besides, the repetitive DNA fragments in many bacterial genomes plus the high error rate of long sequencing data make it still very challenging to accurately assemble their genomes even with a relatively small genome size. Therefore, there is an urgent need for the development of an optimized method to address these issues. Results We developed B-assembler, which is capable of assembling bacterial genomes when there are only long reads or a combination of short and long reads. B-assembler takes advantage of the structural resolving power of long reads and the accuracy of short reads if applicable. It first selects and corrects the ultra-long reads to get an initial contig. Then, it collects the reads overlapping with the ends of the initial contig. This two-round assembling procedure along with optimized error correction enables a high-confidence and circularized genome assembly. Benchmarked on both synthetic and real sequencing data of several species of bacterium, the results show that both long-read-only and hybrid-read modes can accurately assemble circular bacterial genomes free of structural errors and have fewer small errors compared to other assemblers. Conclusions B-assembler provides a better solution to bacterial genome assembly, which will facilitate downstream bacterial genome analysis.
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- 2022
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8. The ‘Giraffe’: discovery of a stripped red giant in an interacting binary with an ∼2 M⊙ lower giant
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T Jayasinghe, Todd A Thompson, C S Kochanek, K Z Stanek, D M Rowan, D V Martin, Kareem El-Badry, P J Vallely, J T Hinkle, D Huber, H Isaacson, J Tayar, K Auchettl, I Ilyin, A W Howard, and C Badenes
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- 2022
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9. A socio-ecological analysis of factors influencing HIV treatment initiation and adherence among key populations in Papua New Guinea
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Elke Mitchell, Avi Hakim, Somu Nosi, Martha Kupul, Ruthy Boli-Neo, Herick Aeno, Michelle Redman-Maclaren, Sophie Ase, Angelyn Amos, Parker Hou, Rebecca Narokobi, Barne Willie, Andrew J. Vallely, John M. Kaldor, Steven G. Badman, and Angela Kelly-Hanku
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Papua New Guinea ,HIV treatment ,Key populations ,Qualitative ,Adherence ,HIV care cascade ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background In Papua New Guinea (PNG) members of key populations, including female sex workers (FSW), men who have sex with men (MSM) and transgender women (TGW), have higher rates of HIV compared to the general adult population and low engagement in HIV care. This paper examines the socio-ecological factors that encourage or hinder HIV treatment initiation and adherence among HIV positive members of key populations in PNG. Methods As part of a larger biobehavioural survey of key populations in PNG, 111 semi-structured interviews were conducted with FSW, MSM and TGW, of whom 28 identified as living with HIV. Interviews from 28 HIV positive participants are used in this analysis of the influences that enabled or inhibited HIV treatment initiation and treatment adherence. Results Enablers included awareness of the biomedical benefits of treatment; experiences of the social, familial and health benefits of early treatment initiation and adherence; support provided by family and friends; and non-judgmental and supportive HIV service provision. Factors that inhibited treatment initiation and adherence included perception of good health and denial of HIV diagnosis; poor family support following positive diagnosis; and anonymity and stigma concerns in HIV care services. Conclusion Exploring health promotion messages that highlight the positive health impacts of early treatment initiation and adherence; providing client-friendly services and community-based treatment initiation and supply; and rolling out HIV viral load testing across the country could improve health outcomes for these key populations.
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- 2021
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10. High-cadence, early-time observations of core-collapse supernovae from the TESS prime mission
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P J Vallely, C S Kochanek, K Z Stanek, M Fausnaugh, and B J Shappee
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- 2020
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11. One size does not fit all: HIV prevalence and correlates of risk for men who have sex with men, transgender women in multiple cities in Papua New Guinea
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Avi J. Hakim, Kelsey Coy, Steven G. Badman, Barne Willie, Rebecca Narokobi, Josephine Gabuzzi, Simon Pekon, Martha Kupul, Parker Hou, Herick Aeno, Ruthy Neo Boli, Joshua Nembari, Sophie Ase, Angelyne Amos, Nick Dala, Damian Weikum, Steven Callens, John M. Kaldor, Andrew J. Vallely, Angela Kelly-Hanku, and on behalf of the Kauntim mi tu Study Team
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Papua New Guinea ,HIV correlates ,Men who have sex with men ,Transgender women ,Respondent-driven ,sampling. ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background Biobehavioral data about men who have sex with men (MSM) and transgender women (TGW) in Papua New Guinea (PNG) are limited to those who sell sex. Information about those MSM and TGW who do not sell sex is necessary to guide HIV prevention and treatment efforts. Methods We conducted respondent-driven sampling (RDS) surveys among MSM and TGW in Port Moresby, Lae, and Mt. Hagen, PNG from in 2016 and 2017. Eligibility criteria was: aged > 12 years, born male, could speak English or Tok Pisin and had oral or anal sex with another person born male in the past 6 months. Participants were interviewed face-to-face and offered rapid HIV testing. Weighted data analysis was conducted using RDS-Analyst (v. 0.62). Results We enrolled 400 participants in Port Moresby, 352 in Lae, and 111 in Mt. Hagen. In the last six months, 73.2% of MSM/TGW in Port Moresby, 77.9% in Lae, and 75.9% in Mt. Hagen, had a concurrent sexual partnership. Upwards of 70% of MSM/TGW in all three cities had sex with a woman in the same period. Less than half of MSM/TGW had ever tested for HIV. HIV prevalence among MSM/TGW was 8.5% in Port Moresby and 6.9% in Lae. Among participants in Mt. Hagen it was 1.3%. HIV was associated with not having sex with a woman in the last six months and sexually transmitted disease symptoms in the last 12 months in Port Moresby and Lae. In Port Moresby, it was also associated with an uncut foreskin, and in Lae with earning income in the formal sector and being unable to rely on other MSM or TGW to accompany them to healthcare services. Conclusions The large proportion of MSM and TGW with concurrent sexual partnerships, combined with the low testing coverage, indicates strong potential for the spread of HIV. The different correlates of HIV in Port Moresby and Lae highlight the importance of conducting surveys in multiple locations and using data to develop locally appropriate interventions even within a country.
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- 2019
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12. Developing a culturally appropriate illustrated tool for the self-collection of anorectal specimens for the testing of sexually transmitted infections: lessons from Papua New Guinea
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Angela Kelly-Hanku, Stephen Bell, Sophie Ase, Ruthy Boli-Neo, Andrew J. Vallely, Steven G. Badman, Claire E. Nightingale, and Johanna Wapling
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Anorectal STIs ,Papua New Guinea ,Self-collection ,STI testing ,Culturally appropriate ,Key populations ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background Papua New Guinea (PNG) has a high prevalence of sexually transmitted infections (STIs). There is increasing evidence that anorectal STIs are important in terms of the dual epidemics of HIV and STIs in this setting. At the time of this study, anorectal STI testing was not possible, and there was no mechanism for self-collection of anorectal specimen among at risk ‘key populations’. This paper documents the development of a culturally appropriate tool that has been used to facilitate self-collection of anorectal specimens with key populations in PNG. Methods This qualitative study involved four focus groups conducted with a purposive sample of 35 participants, including female sex workers, men who have sex with men and transgender women in Port Moresby and Goroka in 2015. During focus groups, participants reviewed and provided critical feedback for the adaption of a previously piloted and published pictorial anorectal specimen collection tool for use with key populations in PNG. Results The final instruction tools are presented in English language and Tok Pisin. To develop these, participants feedback resulted in six key areas of the existing instruction document being modified to ensure it was appropriate for use in PNG. These included translating complex words for sexual health issues (i.e. ‘STIs’, ‘anorectal STIs’, ‘anus’, ‘anal sex’), biomedical instruments (i.e. ‘specimen bottle’, ‘specimen packet’ and ‘swab’), and aspects of the clinical procedure (i.e. inserting the swab 3–4 cm into the anus to collect a specimen). The visual identity of the graphics was redesigned to localise the images for use in PNG. Conclusions This paper describes the development of a culturally and linguistically appropriate tool for a biomedical and clinical intervention with key populations in PNG based around self-collection of anorectal specimens for molecular STI testing. The final tools have been used to facilitate the self-collection of anorectal specimens following a clear clinical protocol during a large bio-behavioural survey in PNG.
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- 2019
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13. Performance of clinical screening algorithms comprising point-of-care HPV-DNA testing using self-collected vaginal specimens, and visual inspection of the cervix with acetic acid, for the detection of underlying high-grade squamous intraepithelial lesions in Papua New Guinea
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Pamela J. Toliman, John M. Kaldor, Steven G. Badman, Josephine Gabuzzi, Selina Silim, Antonia Kumbia, Benny Kombuk, Zure Kombati, Gloria Munnull, Rebecca Guy, Lisa M. Vallely, Angela Kelly-Hanku, Handan Wand, Claire Ryan, Grace Tan, Julia Brotherton, Marion Saville, Glen D.L. Mola, Suzanne M. Garland, Sepehr N. Tabrizi, and Andrew J. Vallely
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Infectious and parasitic diseases ,RC109-216 - Abstract
The performance of different clinical screening algorithms comprising point-of-care HPV-DNA testing using self-collected vaginal (‘V’) specimens, and visual inspection of the cervix with acetic acid (VIA) was evaluated in Papua New Guinea.Women aged 30–59 years provided V specimens that were tested at point-of-care using the Xpert HPV Test (Cepheid, Sunnyvale, CA). A clinician-collected cervical (‘C’) specimen was then collected for point-of-care Xpert testing, and liquid-based cytology (LBC). Following this, VIA examination was conducted, blind to HPV test results, and ablative cervical cryotherapy provided if indicated. Detection of high-grade squamous intraepithelial lesion (HSIL) by LBC was the reference standard used to evaluate clinical screening algorithms.Of 1005 women, 36 had HSIL+. Xpert HPV Test performance using V specimens (sensitivity 91.7%, specificity 87.0%, PPV 34.0%, NPV 99.3%) was superior to VIA examination alone (51.5%, 81.4%, 17.5%, 95.6% respectively) in predicting underlying HSIL+. A screening algorithm comprising V specimen HPV testing followed by VIA examination had low sensitivity (45.5%) but comparable specificity, PPV and NPV to HPV testing alone (96.3%, 45.5%, 96.3% respectively).A ‘test-and-treat’ screening algorithm based on point-of-care HPV testing of V specimens had superior performance compared with either VIA examination alone, or a combined screening algorithm comprising HPV testing plus VIA. Keywords: Cervical cancer, HPV, Screening, Self-collect, Papua New Guinea, Visual inspection with acetic acid
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- 2018
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14. Economic evaluation of point-of-care testing and treatment for sexually transmitted and genital infections in pregnancy in low- and middle-income countries: A systematic review.
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Olga P M Saweri, Neha Batura, Rabiah Al Adawiyah, Louise M Causer, William S Pomat, Andrew J Vallely, and Virginia Wiseman
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Medicine ,Science - Abstract
BackgroundSexually transmitted and genital infections in pregnancy are associated with adverse pregnancy and birth outcomes. Point-of-care tests for these infections facilitate testing and treatment in a single antenatal clinic visit and may reduce the risk of adverse outcomes. Successful implementation and scale-up depends on understanding comparative effectiveness of such programmes and their comparative costs and cost effectiveness. This systematic review synthesises and appraises evidence from economic evaluations of point-of-care testing and treatment for sexually transmitted and genital infections among pregnant women in low- and middle-income countries.MethodsMedline, Embase and Web of Science databases were comprehensively searched using pre-determined criteria. Additional literature was identified by searching Google Scholar and the bibliographies of all included studies. Economic evaluations were eligible if they were set in low- and middle-income countries and assessed antenatal point-of-care testing and treatment for syphilis, chlamydia, gonorrhoea, trichomoniasis, and/or bacterial vaginosis. Studies were analysed using narrative synthesis. Methodological and reporting standards were assessed using two published checklists.ResultsSixteen economic evaluations were included in this review; ten based in Africa, three in Latin and South America and three were cross-continent comparisons. Fifteen studies assessed point-of-care testing and treatment for syphilis, while one evaluated chlamydia. Key drivers of cost and cost-effectiveness included disease prevalence; test, treatment, and staff costs; test sensitivity and specificity; and screening and treatment coverage. All studies met 75% or more of the criteria of the Drummond Checklist and 60% of the Consolidated Health Economics Evaluation Reporting Standards.ConclusionsGenerally, point-of-care testing and treatment was cost-effective compared to no screening, syndromic management, and laboratory-based testing. Future economic evaluations should consider other common infections, and their lifetime impact on mothers and babies. Complementary affordability and equity analyses would strengthen the case for greater investment in antenatal point-of-care testing and treatment for sexually transmitted and genital infections.
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- 2021
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15. The ASAS-SN bright supernova catalogue – IV. 2017
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T W-S Holoien, J S Brown, P J Vallely, K Z Stanek, C S Kochanek, B J Shappee, J L Prieto, Subo Dong, J Brimacombe, D W Bishop, S Bose, J F Beacom, D Bersier, Ping Chen, L Chomiuk, E Falco, S Holmbo, T Jayasinghe, N Morrell, G Pojmanski, J V Shields, J Strader, M D Stritzinger, Todd A Thompson, P R Woźniak, G Bock, P Cacella, J G Carballo, I Cruz, E Conseil, R G Farfan, J M Fernandez, S Kiyota, R A Koff, G Krannich, P Marples, G Masi, L A G Monard, J A Muñoz, B Nicholls, R S Post, G Stone, D L Trappett, and W S Wiethoff
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- 2019
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16. HPV vaccination in Papua New Guinea to prevent cervical cancer in women: Gender, sexual morality, outsiders and the de-feminization of the HPV vaccine
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Angela Kelly-Hanku, Jamee Newland, Peter Aggleton, Sophie Ase, Herick Aeno, Voletta Fiya, Lisa M. Vallely, Pamela J. Toliman, Glen DL. Mola, John M. Kaldor, and Andrew J. Vallely
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Infectious and parasitic diseases ,RC109-216 - Abstract
Papua New Guinea has among the highest estimated burden of cervical cancer globally, but currently lacks national cervical screening or human papillomavirus (HPV) vaccination programmes. The Papua New Guinean government is committed to introducing the HPV vaccine for primary prevention, but locally-relevant research evidence is not available to guide implementation. Experience from earlier Papua New Guinean health programmes suggests that appropriate engagement with local health cosmologies and cultures for health/wellbeing, illness/disease, and recognition of the role of ‘outsiders’ in preventing, promoting or contributing to sickness, are essential to the successful introduction of biomedical interventions in this setting. We describe findings from a multi-site qualitative study undertaken in three provinces in Papua New Guinea (2012-14). Twenty-one gender specific focus group discussions and 82 semi-structured interviews, with a total of 208 participants, were conducted. There was strong community support for the introduction of the HPV vaccine for cervical cancer prevention in Papua New Guinea. Significantly, and despite being officially discussed in the context of a planned future intervention focusing on vaccinating young girls to prevent cervical cancer, the intervention was de-feminised, where both girls and boys were supported to be vaccinated in any HPV programme in Papua New Guinea.
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- 2019
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17. Use of quantitative PCR to assess the efficacy of albendazole against Necator americanus and Ascaris spp. in Manufahi District, Timor-Leste
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Susana Vaz Nery, Jessica Qi, Stacey Llewellyn, Naomi E. Clarke, Rebecca Traub, Darren J. Gray, Andrew J. Vallely, Gail M. Williams, Ross M. Andrews, James S. McCarthy, and Archie C. A. Clements
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Albendazole ,Efficacy ,Necator americanus ,Ascaris lumbricoides ,Hookworm ,Soil-transmitted helminths ,Infectious and parasitic diseases ,RC109-216 - Abstract
Abstract Background Soil-transmitted helminths (STHs) including Ascaris lumbricoides, Necator americanus, Ancylostoma spp. and Trichuris trichiura are cause of significant global morbidity. To mitigate their disease burden, at-risk groups in endemic regions receive periodic mass drug administration using anthelmintics, most commonly albendazole and mebendazole. Assessing the efficacy of anthelmintic drugs is important for confirming that these regimens are working effectively and that drug resistance has not emerged. In this study we aimed to characterise the therapeutic efficacy of albendazole against Ascaris spp. and N. americanus in Timor-Leste, using a quantitative polymerase chain reaction (qPCR) method for parasite detection and quantification. Results A total of 314 participants from 8 communities in Timor-Leste provided stool samples before and 10–14 days after the administration of a single 400 mg dose of albendazole. Helminth infection status and infection intensity (measured in Ct-values and relative fluorescence units) were determined using qPCR. Efficacy was determined by examining the cure rates and infection intensity reduction rates. Albendazole was found to be highly efficacious against Ascaris spp., with a cure rate of 91.4% (95% CI: 85.9–95.2%) and infection intensity reduction rate of 95.6% (95% CI: 88.3–100%). The drug was less efficacious against N. americanus with a cure rate of 58.3% (95% CI: 51.4–64.9%) and infection intensity reduction rate of 88.9% (95% CI: 84.0–97.0%). Conclusions The observed cure rates and infection intensity reduction rates obtained for Ascaris spp. and to a lower extent N. americanus, demonstrate the continued efficacy of albendazole against these species and its utility as a mass chemotherapy agent in Timor-Leste. Furthermore, this study demonstrates the usefulness of qPCR as a method to measure the efficacy of anthelminthic drugs. Additional research is necessary to translate Ct-values into eggs per gram in a systematic way. Trial registration Australian and New Zealand Clinical Trials Registry 12614000680662 (registered 27 June 2014).
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- 2018
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18. Acceptability of testing for anorectal sexually transmitted infections and self-collected anal swabs in female sex workers, men who have sex with men and transgender women in Papua New Guinea
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Stephen Bell, Johanna Wapling, Sophie Ase, Ruthy Boli-Neo, Andrew J. Vallely, John M. Kaldor, Claire E. Nightingale, and Angela Kelly-Hanku
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Anorectal STIs ,Acceptability ,Anorectal STI testing ,Key populations ,Self-collection ,Papua New Guinea ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background Papua New Guinea (PNG) has some of the highest prevalence of urogenital sexually transmitted infections (STIs) in Pacific Asia, but to date, anorectal STI prevalence data do not exist, and diagnosis of anorectal STIs does not occur. The purpose of this study was to document the acceptability of anorectal STI testing and self-collection of anorectal swabs for testing among populations at risk of anorectal STIs, in advance of a large bio-behavioural survey during which this approach to specimen collection was planned among key populations in PNG. Methods Four focus groups were conducted, collecting data from a purposive sample of 35 members of two civil society groups representing female sex workers, men who have sex with men and transgender women in Port Moresby and Goroka. Results All participants were in favour of anorectal STI testing in PNG. Reasons given for willingness to undertake anorectal STI testing included that anal sex is practised; that anorectal STIs are not perceived to exist; there are self-reported experiences of anorectal symptoms indicative of anorectal STIs; that anorectal STI testing will enhance personal health; and that anorectal STI testing is not currently available in PNG. All participants were confident they could obtain self-collected specimens, although several stated that support from trained health workers should be available for community members who may not feel comfortable with self-collection. Conclusions This qualitative research is the first study of acceptability of anorectal STI testing and specimen self-collection procedures in PNG, and Pacific Asia more broadly. Our qualitative findings show support for anorectal STI testing including the use of self-collected swabs among key populations in PNG. Study findings informed the inclusion of anorectal STI testing in a large bio-behavioural survey to be used to estimate anorectal STI prevalence among key populations in PNG for the first time.
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- 2018
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19. Investigations into the association between soil-transmitted helminth infections, haemoglobin and child development indices in Manufahi District, Timor-Leste
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Suzy J. Campbell, Susana V. Nery, Catherine A. D’Este, Darren J. Gray, James S. McCarthy, Rebecca J. Traub, Ross M. Andrews, Stacey Llewellyn, Andrew J. Vallely, Gail M. Williams, and Archie C. A. Clements
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Soil-transmitted helminths ,Necator americanus ,Ascaris ,Morbidity ,Anaemia ,Stunting ,Infectious and parasitic diseases ,RC109-216 - Abstract
Abstract Background Timor-Leste has a high prevalence of soil-transmitted helminth (STH) infections. High proportions of the population have been reported as being anaemic, and extremely high proportions of children as stunted or wasted. There have been no published analyses of the contributions of STH to these morbidity outcomes in Timor-Leste. Methods Using baseline cross-sectional data from 24 communities (18 communities enrolled in a cluster randomised controlled trial, and identically-collected data from six additional communities), analyses of the association between STH infections and community haemoglobin and child development indices were undertaken. Stool samples were assessed for STH using qPCR and participant haemoglobin, heights and weights were measured. Questionnaires were administered to collect demographic and socioeconomic data. Intensity of infection was categorised using correlational analysis between qPCR quantification cycle values and eggs per gram of faeces equivalents, with algorithms generated from seeding experiments. Mixed-effects logistic and multinomial regression were used to assess the association between STH infection intensity classes and anaemia, and child stunting, wasting and underweight. Results Very high stunting (60%), underweight (60%), and wasting (20%) in children, but low anaemia prevalence (15%), were found in the study communities. STH were not significantly associated with morbidity outcomes. Male children and those in the poorest socioeconomic quintile were significantly more likely to be moderately and severely stunted. Male children were significantly more likely than female children to be severely underweight. Increasing age was also a risk factor for being underweight. Few risk factors emerged for wasting in these analyses. Conclusions According to World Health Organization international reference standards, levels of child morbidity in this population constitute a public health emergency, although the international reference standards need to be critically evaluated for their applicability in Timor-Leste. Strategies to improve child development and morbidity outcomes, for example via nutrition and iron supplementation programmes, are recommended for these communities. Despite the apparent lack of an association from STH in driving anaemia, stunting, wasting and underweight, high endemicity suggests a need for STH control strategies. Trial registration Australian and New Zealand Clinical Trials Registry ACTRN12614000680662 ; retrospectively registered.
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- 2017
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20. Point-of-care testing and treatment of sexually transmitted infections to improve birth outcomes in high-burden, low-income settings: Study protocol for a cluster randomized crossover trial (the WANTAIM Trial, Papua New Guinea) [version 2; peer review: 2 approved]
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Andrew J. Vallely, William S. Pomat, Caroline Homer, Rebecca Guy, Stanley Luchters, Glen D. L. Mola, Grace Kariwiga, Lisa M. Vallely, Virginia Wiseman, Chris Morgan, Handan Wand, Stephen J. Rogerson, Sepehr N. Tabrizi, David M. Whiley, Nicola Low, Rosanna Peeling, Peter Siba, Michaela Riddell, Moses Laman, John Bolnga, Leanne J. Robinson, Jacob Morewaya, Steven G. Badman, Neha Batura, Angela Kelly-Hanku, Pamela J. Toliman, Wilfred Peter, Delly Babona, Elizabeth Peach, Suzanne M. Garland, and John M. Kaldor
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Medicine ,Science - Abstract
Background: Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis and bacterial vaginosis have been associated with preterm birth and low birth weight, and are highly prevalent among pregnant women in many low- and middle-income settings. There is conflicting evidence on the potential benefits of screening and treating these infections in pregnancy. Newly available diagnostic technologies make it possible, for the first time, to conduct definitive field trials to fill this knowledge gap. The primary aim of this study is to evaluate whether antenatal point-of-care testing and immediate treatment of these curable sexually transmitted and genital infections (STIs) leads to reduction in preterm birth and low birth weight. Methods: The Women and Newborn Trial of Antenatal Interventions and Management (WANTAIM) is a cluster-randomised crossover trial in Papua New Guinea to compare point-of-care STI testing and immediate treatment with standard antenatal care (which includes the WHO-endorsed STI ‘syndromic’ management strategy based on clinical features alone without laboratory confirmation). The unit of randomisation is a primary health care facility and its catchment communities. The primary outcome is a composite measure of two events: the proportion of women and their newborns in each trial arm, who experience either preterm birth (delivery
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- 2019
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21. SN 2019yvq Does Not Conform to SN Ia Explosion Models
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M. A. Tucker, C. Ashall, B. J. Shappee, P. J. Vallely, C. S. Kochanek, M. E. Huber, G. S. Anand, J. V. Keane, E. Y. Hsiao, and T. W.-S. Holoien
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- 2021
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22. Seeing Double: ASASSN-18bt Exhibits a Two-component Rise in the Early-time K2 Light Curve
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B. J. Shappee, T. W.-S. Holoien, M. R. Drout, K. Auchettl, M. D. Stritzinger, C. S. Kochanek, K. Z. Stanek, E. Shaya, G. Narayan, J. S. Brown, S. Bose, D. Bersier, J. Brimacombe, Ping Chen, Subo Dong, S. Holmbo, B. Katz, J. A. Munoz, R. L. Mutel, R. S. Post, J. L. Prieto, J. Shields, D. Tallon, T. A. Thompson, P. J. Vallely, S. Villanueva Jr, L. Denneau, H. Flewelling, A. N. Heinze, K. W. Smith, B. Stalder, J. L. Tonry, H. Weiland, T. Barclay, G. Barentsen, A. M. Cody, J. Dotson, F. Foerster, P. Garnavich, M. Gully-Santiago, C. Hedges, S. Howell, D. Kasen, S. Margheim, R. Mushotzky, A. Rest, B. E. Tucker, A. Villar, A. Zenteno, G. Beerman, R. Bjella, G. Castillo, J. Coughlin, B. Elsaesser, S. Flynn, R. Gangopadhyay, K. Griest, M. Hanley, J. Kampmeier, R. Kloetzel, L. Kohnert, C. Labonde, R. Larsen, K. A. Larson, K. M. McCalmont-Everton, C. McGinn, L. Migliorini, J. Moffatt, M. Muszynski, V. Nystrom, D. Osborne, M. Packard, C. A. Peterson, M. Redick, L. H. Reedy, S. E. Ross, B. Spencer, K. Steward, J. E. Van Cleve, J. Vinícius de Miranda-Cardoso, T. Weschler, A. Wheaton, J. Bulger, K. C. Chambers, H. A. Flewelling, M. E. Huber, T. B. Lowe, E. A. Magnier, A. S. B. Schultz, C. Z. Waters, M. Willman, E. Baron, Zhihao Chen, James M. Derkacy, Fang Huang, Linyi Li, Wenxiong Li, Xue Li, Jun Mo, Liming Rui, Hanna Sai, Lifan Wang, Lingzhi Wang, Xiaofeng Wang, Danfeng Xiang, Jicheng Zhang, Jujia Zhang, Kaicheng Zhang, Tianmeng Zhang, Xinghan Zhang, Xulin Zhao, P. J. Brown, J. J. Hermes, J. Nordin, S. Points, A. Sodor, and G. M. Strampelli
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Astrophysics - Abstract
On 2018 February 4.41, the All-Sky Automated Survey for SuperNovae (ASAS-SN) discovered ASASSN-18bt in the K2 Campaign 16 field. With a redshift of z=0.01098 and a peak apparent magnitude of B(max)=14.31, ASASSN-18bt is the nearest and brightest SNe Ia yet observed by the Kepler spacecraft. Here we present the discovery of ASASSN-18bt, the K2 light curve, and prediscovery data from ASAS-SN and the Asteroid Terrestrial-impact Last Alert System. The K2 early-time light curve has an unprecedented 30-minute cadence and photometric precision for an SN Ia light curve, and it unambiguously shows a ∼4 day nearly linear phase followed by a steeper rise. Thus, ASASSN-18bt joins a growing list of SNe Ia whose early light curves are not well described by a single power law. We show that a double-power-law model fits the data reasonably well, hinting that two physical processes must be responsible for the observed rise. However, we find that current models of the interaction with a nondegenerate companion predict an abrupt rise and cannot adequately explain the initial, slower linear phase. Instead, we find that existing published models with shallow 56Ni are able to span the observed behavior and, with tuning, may be able to reproduce the ASASSN-18bt light curve. Regardless, more theoretical work is needed to satisfactorily model this and other early-time SNe Ia light curves. Finally, we use Swift X-ray nondetections to constrain the presence of circumstellar material (CSM) at much larger distances and lower densities than possible with the optical light curve. For a constant-density CSM, these nondetections constrain ρ<4.5×10(exp 5)per cu.cm at a radius of 4×10(exp 15) cm from the progenitor star. Assuming a wind-like environment, we place mass loss limits of M˙ < 8 x 10(exp -6) M(ʘ)per yr for v(w)=100 km/s, ruling out some symbiotic progenitor systems. This work highlights the power of well-sampled early-time data and the need for immediate multiband, high-cadence follow-up for progress in understanding SNe Ia.
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- 2018
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23. Photometric and Spectroscopic Properties of Type Ia Supernova 2018oh with Early Excess Emission from the Kepler 2 Observations
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Thomas Barclay, W. Li, X. Wang, J. Vinko, J. Mo, G. Hosseinzadeh, D. J. Sand, J. Zhang, H. Lin, T. Zhang, L. Wang, Z. Chen, D. Xiang, L. Rui, F. Huang, X. Li, X. Zhang, L. Li, E. Baron, J. M. Derkacy, X. Zhao, H. Sai, K. Zhang, D. A. Howell, C. McCully, I. Arcavi, S. Valenti, D. Hiramatsu, J. Burke, A. Rest, P. Garnavich, B. E. Tucker, G. Narayan, E. Shaya, S. Margheim, A. Zenteno, A. Villar, G. Dimitriadis, R. J. Foley, Y.-C. Pan, D. A. Coulter, O. D. Fox, S. W. Jha, D. O. Jones, D. N. Kasen, C. D. Kilpatrick, A. L. Piro, A. G. Riess, C. Rojas-Bravo, B. J. Shappee, T. W.-S. Holoien, K. Z. Stanek, M. R. Drout, K. Auchettl, C. S. Kochanek, J. S. Brown, S. Bose, D. Bersier, J. Brimacombe, P. Chen, S. Dong, S. Holmbo, J. A. Munoz, R. L. Mutel, R. S. Post, J. L. Prieto, J. Shields, D. Tallon, T. A. Thompson, P. J. Vallely, S. Villanueva Jr, S. J. Smartt, K. W. Smith, K. C. Chambers, H. A. Flewelling, M. E. Huber, E. A. Magnier, C. Z. Waters, A. S. B. Schultz, J. Bulger, T. B. Lowe, M. Willman, K. Sarneczky, A. Pal, J. C. Wheeler, A. Bodi, Zs. Bognar, B. Csak, B. Cseh, G. Csornyei, O. Hanyecz, B. Ignacz, Cs. Kalup, R. Konyves-Toth, L. Kriskovics, A. Ordasi, I. Rajmon5, A. Sodor, R. Szabo, R. Szakats, G. Zsidi, P. Milne, J. E. Andrews, N. Smith, C. Bilinski, P. J. Brown, J. Nordin, S. C. Williams, L. Galbany, J. Palmerio, I. M. Hook, C. Inserra, K. Maguire, Regis Cartier, A. Razza, C. P. Gutierrez, J. J. Hermes, J. S. Reding, B. C. Kaiser, J. L. Tonry, A. N. Heinze, L. Denneau, H. Weiland, B. Stalder, G. Barentsen, J Dotson, T Barclay, M Gully-Santiago, C. Hedges, A. M. Cody, S Howell, J. Coughlin, J. E. Van Cleve, J. Vinicius de Miranda Cardoso, K. A. Larson, K. M. McCalmont-Everton, C. A. Peterson, S. E. Ross, L. H. Reedy, D. Osborne, C. McGinn, L. Kohnert, L. Migliorini, A. Wheaton, B. Spencer, C. Labonde, G. Castillo, G. Beerman, K. Steward, M. Hanley, R. Larsen, R. Gangopadhyay, R. Kloetzel, T. Weschler, V. Nystrom, J. Moffatt, M. Redick, K. Griest, M. Packard, M. Muszynski, J. Kampmeier, R. Bjella, S. Flynn, and B. Elsaesser
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Astrophysics ,Astronomy - Abstract
Supernova (SN) 2018oh (ASASSN-18bt) is the first spectroscopically confirmed Type Ia supernova (SN Ia) observed in the Kepler field. The Kepler data revealed an excess emission in its early light curve, allowing us to place interesting constraints on its progenitor system. Here we present extensive optical, ultraviolet, and nearinfrared photometry, as well as dense sampling of optical spectra, for this object. SN 2018oh is relatively normal in its photometric evolution, with a rise time of 18.3±0.3 days and Δ(m15)(B)=0.96±0.03 mag, but it seems to have bluer B−V colors. We construct the “UVOIR” bolometric light curve having a peak luminosity of 1.49×10(Exp 43) erg/s, from which we derive a nickel mass as 0.55±0.04M(ʘ) by fitting radiation diffusion models powered by centrally located 56Ni. Note that the moment when nickel-powered luminosity starts to emerge is +3.85 days after the first light in the Kepler data, suggesting other origins of the early-time emission, e.g., mixing of 56Ni to outer layers of the ejecta or interaction between the ejecta and nearby circumstellar material or a nondegenerate companion star. The spectral evolution of SN 2018oh is similar to that of a normal SN Ia but is characterized by prominent and persistent carbon absorption features. The CII features can be detected from the early phases to about 3 weeks after the maximum light, representing the latest detection of carbon ever recorded in an SN Ia. This indicates that a considerable amount of unburned carbon exists in the ejecta of SN 2018oh and may mix into deeper layers.
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- 2018
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24. Early-time Light Curves of Type Ia Supernovae Observed with TESS
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M. M. Fausnaugh, P. J. Vallely, C. S. Kochanek, B. J. Shappee, K. Z. Stanek, M. A. Tucker, George R. Ricker, Roland Vanderspek, David W. Latham, S. Seager, Joshua N. Winn, Jon M. Jenkins, Zachory K. Berta-Thompson, Tansu Daylan, John P. Doty, Gábor Fűrész, Alan M. Levine, Robert Morris, András Pál, Lizhou Sha, Eric B. Ting, and Bill Wohler
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- 2021
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25. Water, Sanitation and Hygiene (WASH) and environmental risk factors for soil-transmitted helminth intensity of infection in Timor-Leste, using real time PCR.
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Suzy J Campbell, Susana V Nery, Rebecca Wardell, Catherine A D'Este, Darren J Gray, James S McCarthy, Rebecca J Traub, Ross M Andrews, Stacey Llewellyn, Andrew J Vallely, Gail M Williams, and Archie C A Clements
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Arctic medicine. Tropical medicine ,RC955-962 ,Public aspects of medicine ,RA1-1270 - Abstract
BACKGROUND:No investigations have been undertaken of risk factors for intensity of soil-transmitted helminth (STH) infection in Timor-Leste. This study provides the first analysis of risk factors for intensity of STH infection, as determined by quantitative PCR (qPCR), examining a broad range of water, sanitation and hygiene (WASH) and environmental factors, among communities in Manufahi District, Timor-Leste. METHODS:A baseline cross-sectional survey of 18 communities was undertaken as part of a cluster randomised controlled trial, with additional identically-collected data from six other communities. qPCR was used to assess STH infection from stool samples, and questionnaires administered to collect WASH, demographic, and socioeconomic data. Environmental information was obtained from open-access sources and linked to infection outcomes. Mixed-effects multinomial logistic regression was undertaken to assess risk factors for intensity of Necator americanus and Ascaris infection. RESULTS:2152 participants provided stool and questionnaire information for this analysis. In adjusted models incorporating WASH, demographic and environmental variables, environmental variables were generally associated with infection intensity for both N. americanus and Ascaris spp. Precipitation (in centimetres) was associated with increased risk of moderate-intensity (adjusted relative risk [ARR] 6.1; 95% confidence interval [CI] 1.9-19.3) and heavy-intensity (ARR 6.6; 95% CI 3.1-14.1) N. americanus infection, as was sandy-loam soil around households (moderate-intensity ARR 2.1; 95% CI 1.0-4.3; heavy-intensity ARR 2.7; 95% CI 1.6-4.5; compared to no infection). For Ascaris, alkaline soil around the household was associated with reduced risk of moderate-intensity infection (ARR 0.21; 95% CI 0.09-0.51), and heavy-intensity infection (ARR 0.04; 95% CI 0.01-0.25). Few WASH risk factors were significant. CONCLUSION:In this high-prevalence setting, strong risk associations with environmental factors indicate that anthelmintic treatment alone will be insufficient to interrupt STH transmission, as conditions are favourable for ongoing environmental transmission. Integrated STH control strategies should be explored as a priority.
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- 2017
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26. The 'Giraffe': Discovery of a stripped red giant in an interacting binary with a ${\sim}2~M_\odot$ lower giant
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T Jayasinghe, Todd A Thompson, C S Kochanek, K Z Stanek, D M Rowan, D V Martin, Kareem El-Badry, P J Vallely, J T Hinkle, D Huber, H Isaacson, J Tayar, K Auchettl, I Ilyin, A W Howard, and C Badenes
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Astrophysics - Solar and Stellar Astrophysics ,Space and Planetary Science ,FOS: Physical sciences ,Astronomy and Astrophysics ,Solar and Stellar Astrophysics (astro-ph.SR) - Abstract
We report the discovery of a stripped giant + lower giant binary, 2M04123153+6738486 (2M0412), identified during a search for non-interacting compact object-star binaries. 2M0412 is an evolved ($T_{\rm eff, giant}\simeq4000$ K), luminous ($L_{\rm giant}\simeq150~L_\odot$) red giant in a circular $P=81.2$ day binary. 2M0412 is a known variable star previously classified as a semi-regular variable. The cross-correlation functions of follow-up Keck/HIRES and LBT/PEPSI spectra show an RV-variable second component with implied mass ratio $q=M_{\rm giant}/M_{\rm comp}\simeq0.20\pm0.01$. The ASAS-SN, ATLAS, TESS and ZTF light curves show that the giant is a Roche lobe filling ellipsoidal variable with an inclination of $49.4^\circ{}\pm{0.3^{\circ}}$, and a giant mass of $M_{\rm giant}=0.38\pm0.01~ M_\odot$ for a distance of $\simeq3.7$ kpc. The mass of the giant indicates that its envelope has been stripped. The giant companion on the lower red giant branch has a mass of $M_{\rm comp}=1.91\pm0.03~M_\odot$ with $T_{\rm eff, comp}\simeq5000$ K, $L_{\rm comp}\simeq60~L_\odot$ and $R_{\rm comp}\simeq11~R_\odot$. We also identify an orbital phase dependent, broad $\rm H\alpha$ emission line which could indicate ongoing accretion from the stripped red giant onto the companion., Comment: Revised version of the paper following comments from the referee, submitted to MNRAS. arXiv admin note: text overlap with arXiv:2101.02212
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- 2022
27. The ASAS-SN Bright Supernova Catalog -- V. 2018-2020
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K D Neumann, T W-S Holoien, C S Kochanek, K Z Stanek, P J Vallely, B J Shappee, J L Prieto, T Pessi, T Jayasinghe, J Brimacombe, D Bersier, E Aydi, C Basinger, J F Beacom, S Bose, J S Brown, P Chen, A Clocchiatti, D D Desai, Subo Dong, E Falco, S Holmbo, N Morrell, J V Shields, K V Sokolovsky, J Strader, M D Stritzinger, S Swihart, T A Thompson, Z Way, L Aslan, D W Bishop, G Bock, J Bradshaw, P Cacella, N Castro-Morales, E Conseil, R Cornect, I Cruz, R G Farfan, J M Fernandez, A Gabuya, J-L Gonzalez-Carballo, M R Kendurkar, S Kiyota, R A Koff, G Krannich, P Marples, G Masi, L A G Monard, J A Muñoz, B Nicholls, R S Post, Z Pujic, G Stone, L Tomasella, D L Trappett, and W S Wiethoff
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High Energy Astrophysical Phenomena (astro-ph.HE) ,Space and Planetary Science ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics - High Energy Astrophysical Phenomena - Abstract
We catalog the 443 bright supernovae discovered by the All-Sky Automated Survey for Supernovae (ASAS-SN) in $2018-2020$ along with the 519 supernovae recovered by ASAS-SN and 516 additional $m_{peak}\leq18$ mag supernovae missed by ASAS-SN. Our statistical analysis focuses primarily on the 984 supernovae discovered or recovered in ASAS-SN $g$-band observations. The complete sample of 2427 ASAS-SN supernovae includes earlier $V$-band samples and unrecovered supernovae. For each supernova, we identify the host galaxy, its UV to mid-IR photometry, and the offset of the supernova from the center of the host. Updated light curves, redshifts, classifications, and host galaxy identifications supersede earlier results. With the increase of the limiting magnitude to $g\leq18$ mag, the ASAS-SN sample is roughly complete up to $m_{peak}=16.7$ mag and is $90\%$ complete for $m_{peak}\leq17.0$ mag. This is an increase from the $V$-band sample where it was roughly complete up to $m_{peak}=16.2$ mag and $70\%$ complete for $m_{peak}\leq17.0$ mag., Comment: 14 pages, 7 figures, 4 tables. Updated to reflect changes made in the published version. Tables containing the catalog data presented in this submission are included in machine-readable format as ancillary files
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- 2022
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28. Forbidden hugs in pandemic times
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Y.-Z. Cai, A. Pastorello, M. Fraser, X.-F. Wang, A. V. Filippenko, A. Reguitti, K. C. Patra, V. P. Goranskij, E. A. Barsukova, T. G. Brink, N. Elias-Rosa, H. F. Stevance, W. Zheng, Y. Yang, K. E. Atapin, S. Benetti, T. J. L. de Boer, S. Bose, J. Burke, R. Byrne, E. Cappellaro, K. C. Chambers, W.-L. Chen, N. Emami, H. Gao, D. Hiramatsu, D. A. Howell, M. E. Huber, E. Kankare, P. L. Kelly, R. Kotak, T. Kravtsov, V. Yu. Lander, Z.-T. Li, C.-C. Lin, P. Lundqvist, E. A. Magnier, E. A. Malygin, N. A. Maslennikova, K. Matilainen, P. A. Mazzali, C. McCully, J. Mo, S. Moran, M. Newsome, D. V. Oparin, E. Padilla Gonzalez, T. M. Reynolds, N. I. Shatsky, S. J. Smartt, K. W. Smith, M. D. Stritzinger, A. M. Tatarnikov, G. Terreran, R. I. Uklein, G. Valerin, P. J. Vallely, O. V. Vozyakova, R. Wainscoat, S.-Y. Yan, J.-J. Zhang, T.-M. Zhang, S. G. Zheltoukhov, R. Dastidar, M. Fulton, L. Galbany, A. Gangopadhyay, H.-W. Ge, C. P. Gutiérrez, H. Lin, K. Misra, Z.-W. Ou, I. Salmaso, L. Tartaglia, L. Xiao, and X.-H. Zhang
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close [binaries] ,STELLAR MERGERS ,DATA RELEASE ,Astronomy and Astrophysics ,TRANSIENT ,V4332 SAGITTARII ,EVOLUTION ,RICH CIRCUMSTELLAR MEDIUM ,individual: AT 2021biy [stars] ,ELECTRON-CAPTURE SUPERNOVAE ,Space and Planetary Science ,DUSTY AFTERMATH ,V838 MONOCEROTIS ,winds, outflows [stars] ,SN HUNT 248 - Abstract
We present an observational study of the luminous red nova (LRN) AT 2021biy in the nearby galaxy NGC 4631. The field of the object was routinely imaged during the pre-eruptive stage by synoptic surveys, but the transient was detected only at a few epochs from ∼231 days before maximum brightness. The LRN outburst was monitored with unprecedented cadence both photometrically and spectroscopically. AT 2021biy shows a short-duration blue peak, with a bolometric luminosity of ∼1.6 × 1041 erg s−1, followed by the longest plateau among LRNe to date, with a duration of 210 days. A late-time hump in the light curve was also observed, possibly produced by a shell-shell collision. AT 2021biy exhibits the typical spectral evolution of LRNe. Early-time spectra are characterised by a blue continuum and prominent H emission lines. Then, the continuum becomes redder, resembling that of a K-type star with a forest of metal absorption lines during the plateau phase. Finally, late-time spectra show a very red continuum (TBB ≈ 2050 K) with molecular features (e.g., TiO) resembling those of M-type stars. Spectropolarimetric analysis indicates that AT 2021biy has local dust properties similar to those of V838 Mon in the Milky Way Galaxy. Inspection of archival Hubble Space Telescope data taken on 2003 August 3 reveals a ∼20 M⊙ progenitor candidate with log (L/L⊙) = 5.0 dex and Teff = 5900 K at solar metallicity. The above luminosity and colour match those of a luminous yellow supergiant. Most likely, this source is a close binary, with a 17–24 M⊙ primary component.
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- 2022
29. The 2019 outburst of the 2005 classical nova V1047 Cen: a record breaking dwarf nova outburst or a new phenomenon?
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E. Aydi, K. V. Sokolovsky, J. S. Bright, E. Tremou, M. M. Nyamai, A. Evans, J. Strader, L. Chomiuk, G. Myers, F-J. Hambsch, K. L. Page, D. A. H. Buckley, C. E. Woodward, F. M. Walter, P. Mróz, P. J. Vallely, T. R. Geballe, D. P. K. Banerjee, R. D. Gehrz, R. P. Fender, M. Gromadzki, A. Kawash, C. Knigge, K. Mukai, U. Munari, M. Orio, V. A. R. M. Ribeiro, J. L. Sokoloski, S. Starrfield, A. Udalski, and P. A. Woudt
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High Energy Astrophysical Phenomena (astro-ph.HE) ,Astrophysics - Solar and Stellar Astrophysics ,Space and Planetary Science ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,Astrophysics::Solar and Stellar Astrophysics ,Astronomy and Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics - High Energy Astrophysical Phenomena ,Solar and Stellar Astrophysics (astro-ph.SR) ,Astrophysics::Galaxy Astrophysics - Abstract
We present a detailed study of the 2019 outburst of the cataclysmic variable V1047~Cen, which hosted a classical nova eruption in 2005. The peculiar outburst occurred 14 years after the classical nova event and lasted for more than 400 days, reaching an amplitude of around 6 magnitudes in the optical. Early spectral follow-up revealed what could be a dwarf nova (accretion disk instability) outburst. However, the outburst duration, high velocity ($>$2000\,km\,s$^{-1}$) features in the optical line profiles, luminous optical emission, and presence of prominent long-lasting radio emission together suggest a phenomenon more exotic and energetic than a dwarf nova outburst. The outburst amplitude, radiated energy, and spectral evolution are also not consistent with a classical nova eruption. There are similarities between V1047~Cen's 2019 outburst and those of classical symbiotic stars, but pre-2005 images of the field of V1047~Cen indicate that the system likely hosts a dwarf companion, implying a typical cataclysmic variable system. Based on our multi-wavelength observations, we suggest that the outburst may have started with a brightening of the disk due to enhanced mass transfer or disk instability, possibly leading to enhanced nuclear shell burning on the white dwarf, which was already experiencing some level of quasi-steady shell burning. This eventually led to the generation of a wind and/or bipolar, collimated outflows. The 2019 outburst of V1047~Cen appears to be unique, and nothing similar has been observed in a typical cataclysmic variable system before, hinting at a potentially new astrophysical phenomenon., 36 pages, 24 figures, 9 tables. Accepted in ApJ
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- 2021
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30. Investigation of InAs/GaAs 1−x Sb x quantum dots for applications in intermediate band solar cells
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Sabina Hatch, M. Fukuda, Tetsuya D. Mishima, V. R. Whiteside, Mukul C. Debnath, A. J. Meleco, M. B. Santos, Yang Cheng, P. J. Vallely, Alison Roeth, Khalid Hossain, Huiyun Liu, and Ian R. Sellers
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010302 applied physics ,Materials science ,Condensed matter physics ,Renewable Energy, Sustainability and the Environment ,Band gap ,02 engineering and technology ,Condensed Matter::Mesoscopic Systems and Quantum Hall Effect ,021001 nanoscience & nanotechnology ,01 natural sciences ,Semimetal ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,law.invention ,Multiple exciton generation ,Condensed Matter::Materials Science ,law ,Quantum dot ,0103 physical sciences ,Solar cell ,Direct and indirect band gaps ,Quantum efficiency ,0210 nano-technology ,Short circuit - Abstract
The reduction of the effective band gap and the valence band offset are observed by increasing the Sb composition in GaAs 1−x Sb x matrix encapsulating InAs quantum dots (QDs). To investigate the potential of the InAs/GaAs 1−x Sb x system for intermediate band solar cells a p-i-n solar cell with a degenerate valence band is grown. An enhancement in the QDs region with increasing temperature is observed in temperature dependent external quantum efficiency measurements. An “s-shape” behavior of the short circuit current density, J Sc , is observed as the temperature increases. Ongoing investigations to illuminate the physical mechanisms contributing to the “s-shape” behavior of J sc will also be presented.
- Published
- 2016
31. Single and multiple respiratory virus infections and severity of respiratory disease: A systematic review
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Paul E. Klapper, K.J. Mutton, P. J. Vallely, and Edward Goka
- Subjects
Pulmonary and Respiratory Medicine ,Pediatrics ,medicine.medical_specialty ,Respiratory Tract Diseases ,MEDLINE ,repisratory virus infections ,Severity of Illness Index ,Article ,Stratified analysis ,Disease severity ,Risk Factors ,medicine ,Forest plot ,Humans ,admission to a general ward ,Pediatrics, Perinatology, and Child Health ,Child ,Coinfection ,co-infections ,business.industry ,Respiratory disease ,dual or multiple infections ,Odds ratio ,medicine.disease ,Confidence interval ,admission to ICU ,Pediatrics, Perinatology and Child Health ,Respiratory virus ,disease severity ,business - Abstract
Introduction There are suggestions that virus co-infections may influence the clinical outcome of respiratory virus illness. We performed a systematic review of the literature to summarise the evidence. Methods MEDLINE, EMBASE, Ovid and WEB of Science databases, major organisation websites and reference lists of published studies were searched. The quality of studies was assessed using the STROBE tool (von Elm et al., 1) Individual study data was analyzed using odds ratios and 95% confidence intervals as a measure of association between exposure (co-infection), patient outcome and results summarised using forest plots and tables Results Nineteen (19) studies from all over the world were identified and included in the review. Most of the studies 73.7% (14/19) recruited children ≤6 years old. Evidence on the role of co-infection in increasing disease severity was inconclusive. In five out of eight studies, co-infection significantly increased risk of admission to general ward (OR: 2.4, 95% CI: 1.3 - 4.4, p = 0.005; OR: 2.4, 95% CI: 1.1 - 7.7, P = 0.04; OR: 3.1, 95% CI: 2.0 - 5.1, p =
- Published
- 2014
32. A novel strategy to express different antigens from one modified vaccinia Ankara vaccine vector
- Author
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Katharina B Lauer, P. J. Vallely, Ray Borrow, Edward A Mc Kenzie, Thomas J Blanchard, Yper Hall, Miles W. Carroll, Paul E. Klapper, and Chikkana P.C. Gowda
- Subjects
Modified vaccinia Ankara ,biology ,viruses ,Japanese encephalitis ,medicine.disease ,biology.organism_classification ,Virology ,law.invention ,Antigen ,law ,medicine ,biology.protein ,Enterovirus 71 ,Recombinant DNA ,Vector (molecular biology) ,Antibody ,Encephalitis - Abstract
To enhance global control of encephalitis and hepatitis caused by rabies-(RABV), Japanese encephalitis-(JEV), hepatitis B-virus (HBV), and enterovirus 71 (EV71) novel immunisation strategies are needed. Therefore, a multipathogen modified Vaccinia Ankara vector, expressing antigens from the above pathogens, was constructed. Two recombinants, one carrying the EV71 and JEV pathogen sequence and one the RABV-HBV pathogen sequence were generated. To ensure similar expression of the antigens, a T7-promoter was linked to the expression cassettes of all pathogen sequences. Direct regulation of this promoter was achieved through co-infection with a second T7-polymerase expressing MVA. Protein expression using this co-infection model of expression was demonstrated in vitro. To investigate the co-infection model of antigen delivery in vivo, a murine immunogenicity study was performed using the MVA-RABV-HBV recombinant. Although, serum antibodies against MVA were induced in all mice, no serum antibodies against RABV or HBV could be detected.
- Published
- 2017
33. Epstein–Barr Virus Infection in Adult Renal Transplant Recipients
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P. J. Vallely, S. L. Johnson, M. Picton, Paul E. Klapper, Muir Morton, B. Coupes, and Stephen A Roberts
- Subjects
Male ,Epstein-Barr Virus Infections ,Herpesvirus 4, Human ,medicine.medical_treatment ,Antibodies, Viral ,Kidney Function Tests ,medicine.disease_cause ,Gastroenterology ,Risk Factors ,hemic and lymphatic diseases ,Immunology and Allergy ,Pharmacology (medical) ,Prospective Studies ,Antigens, Viral ,Aged, 80 and over ,immunosuppression ,Incidence ,Graft Survival ,virus diseases ,Immunosuppression ,Middle Aged ,renal transplantation ,Prognosis ,Biomarker (medicine) ,Female ,Glomerular Filtration Rate ,Adult ,medicine.medical_specialty ,Adolescent ,Renal function ,Virus ,Young Adult ,Internal medicine ,medicine ,Humans ,Epstein-Barr virus ,Epstein–Barr virus infection ,Aged ,Transplantation ,business.industry ,medicine.disease ,Kidney Transplantation ,Epstein–Barr virus ,Lymphoproliferative Disorders ,Transplant Recipients ,Cross-Sectional Studies ,PTLD ,DNA, Viral ,Immunology ,Kidney Failure, Chronic ,business ,Serostatus ,Follow-Up Studies - Abstract
Epstein–Barr virus (EBV) DNAemia in the first year posttransplantation has been studied extensively. There is a paucity of information on prevalence and sequelae of EBV infection in adult renal transplantation beyond the first year. This single-center study examines the relationship between EBV DNAemia and demographic, immunosuppressive, hematologic and infection-related parameters in 499 renal transplant recipients between 1 month and 33 years posttransplant. Participants were tested repeatedly for EBV DNAemia detection over 12 months and clinical progress followed for 3 years. Prevalence of DNAemia at recruitment increased significantly with time from transplant. In multivariate adjusted analyses, variables associated with DNAemia included EBV seronegative status at transplant (p = 0.045), non-White ethnicity (p = 0.014) and previous posttransplant lymphoproliferative disease (PTLD) diagnosis (p = 0.006), while low DNAemia rates were associated with mycophenolate mofetil use (p
- Published
- 2014
34. Viral CNS infections in children from a malaria-endemic area of Malawi: a prospective cohort study
- Author
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Tom Solomon, Malcolm E. Molyneux, Terrie E. Taylor, Paul E. Klapper, Harriet Khofi, Mavuto Mukaka, Brian Faragher, P. J. Vallely, Paul Pensulo, Dan Banda, and Macpherson Mallewa
- Subjects
Male ,Pediatrics ,Malawi ,Endemic Diseases ,viruses ,HIV Infections ,medicine.disease_cause ,wc_500 ,Polymerase Chain Reaction ,Cohort Studies ,0302 clinical medicine ,Epidemiology ,Medicine ,030212 general & internal medicine ,Prospective Studies ,Malaria, Falciparum ,Prospective cohort study ,Child ,ws_450 ,Medicine(all) ,medicine.diagnostic_test ,Coinfection ,lcsh:Public aspects of medicine ,General Medicine ,Articles ,3. Good health ,Cerebral Malaria ,Child, Preschool ,Female ,medicine.medical_specialty ,Adolescent ,030231 tropical medicine ,Plasmodium falciparum ,Malaria, Cerebral ,Virus ,03 medical and health sciences ,parasitic diseases ,Humans ,ws_430 ,business.industry ,Brain biopsy ,Infant ,lcsh:RA1-1270 ,medicine.disease ,wc_750 ,qx_135 ,ws_205 ,Central Nervous System Viral Diseases ,Enterovirus ,Rabies ,business ,Malaria ,ws_440 - Abstract
Summary Background Fever with reduced consciousness is an important cause of hospital admission of children in sub-Saharan Africa, with high mortality. Cerebral malaria, diagnosed when acute Plasmodium falciparum infection and coma are recorded with no other apparent reason, is one important cause. We investigated whether viruses could also be an important cause of CNS infection in such patients, and examined the relative contribution of viral pathogens and malaria parasitaemia. Methods We did a prospective cohort study in Blantyre, Malawi. From March 1, 2002, to Aug 31, 2004, we enrolled children aged between 2 months and 15 years who were admitted to hospital with suspected non-bacterial CNS infections. Children with a cerebrospinal fluid (CSF) white cell count of less than 1000 cells per μL and negative bacterial microscopy and culture were deemed to have suspected viral CNS infection. Blood was examined for asexual forms of P falciparum. PCR was done on CSF or on post-mortem brain biopsy specimens to detect 15 viruses known to cause CNS infection. Findings Full outcome data were available for 513 children with suspected viral CNS infection, of whom 94 (18%) died. 163 children (32%) had P falciparum parasitaemia, of whom 34 (21%) died. At least one virus was detected in the CNS in 133 children (26%), of whom 43 (33%) died. 12 different viruses were detected; adenovirus was the most common, affecting 42 children; mumps, human herpes virus 6, rabies, cytomegalovirus, herpes simplex virus 1, and enterovirus were also important. 45 (9%) of the 513 children had both parasitaemia and viral infection, including 27 (35%) of 78 diagnosed clinically with cerebral malaria. Children with dual infection were more likely to have seizures than were those with parasitaemia alone, viral infection only, or neither (p
- Published
- 2013
35. Investigation of InAs/GaAs1−xSbx quantum dots for applications in intermediate band solar cells
- Author
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Y. Cheng, M. Fukuda, V. R. Whiteside, M. C. Debnath, P. J. Vallely, A. J. Meleco, A. J. Roeth, T. D. Mishima, M. B. Santos, K. Hossain, S. Hatch, H. Y. Liu, and I. R. Sellers
- Published
- 2016
36. Merkel cell polyomavirus DNA in immunocompetent and immunocompromised patients with respiratory disease
- Author
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P. J. Vallely, Bahman Abedi Kiasari, and Paul E. Klapper
- Subjects
Male ,co‐infection ,Merkel cell polyomavirus ,respiratory infection ,Nasopharyngeal aspirate ,Respiratory infection ,Nasopharynx ,Prevalence ,Cluster Analysis ,Child ,Respiratory Tract Infections ,Research Articles ,Phylogeny ,Coinfection ,Merkel cell carcinoma ,Respiratory disease ,Middle Aged ,Co-infection ,immunocompromised ,PCR ,Infectious Diseases ,medicine.anatomical_structure ,Child, Preschool ,Female ,Research Article ,Adult ,Adolescent ,Biology ,Real-Time Polymerase Chain Reaction ,Virus ,Immunocompromised Host ,Young Adult ,Virology ,Lower respiratory tract infection ,medicine ,Humans ,Immunocompromised ,Aged ,Polyomavirus Infections ,Infant, Newborn ,Infant ,Sequence Analysis, DNA ,medicine.disease ,biology.organism_classification ,DNA, Viral ,Immunology ,Respiratory tract - Abstract
Merkel cell polyomavirus (MCPyV) was identified originally in association with a rare but aggressive skin cancer, Merkel cell carcinoma. The virus has since been found in the respiratory tract of some patients with respiratory disease. However, the role of MCPyV in the causation of respiratory disease has not been established. To determine the prevalence of MCPyV in 305 respiratory samples from immunocompetent and immunocompromised patients and evaluate their contribution to respiratory diseases, specimens were screened for MCPyV using single, multiplex, or real‐time PCR; co‐infection with other viruses was examined. Of the 305 samples tested, 10 (3.27%) were positive for MCPyV. The virus was found in two groups of patients: in 6 (2%) nasopharyngeal aspirate samples from children aged 26 days to 7 months who were immunocompetent; and in 4 (1.3%) of nasopharyngeal aspirate samples taken from patients aged 41 to 69 years who were severely immunosuppressed from leukemia or transplant therapy. Both groups had upper or lower respiratory tract infection. Co‐infections with other viruses were found in 30% of the MCPyV positive samples. The data present a pattern of infection similar to that seen with the polyomaviruses JC and BK in which the virus is acquired during childhood, probably by the respiratory route. The viruses then establish latency and become reactivated in the event of immunosuppression. J. Med. Virol. 83:2220–2224, 2011. © 2011 Wiley Periodicals, Inc.
- Published
- 2011
37. Characterization of fHbp , nhba ( gna2132 ), nadA , porA , and Sequence Type in Group B Meningococcal Case Isolates Collected in England and Wales during January 2008 and Potential Coverage of an Investigational Group B Meningococcal Vaccine
- Author
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P. J. Vallely, Stephen J. Gray, Stefania Bambini, Malcolm Guiver, Ray Borrow, Jay Lucidarme, Edward B. Kaczmarski, Alessandro Muzzi, Jamie Findlow, Philipp Oster, Mariagrazia Pizza, and Maurizio Comanducci
- Subjects
Microbiology (medical) ,education.field_of_study ,Invasive disease ,Clinical Biochemistry ,Immunology ,Population ,MeNZB ,Meningococcal vaccine ,Biology ,Meningococcal disease ,medicine.disease ,Virology ,Group B ,Microbiology ,Bacterial protein ,Genotype ,medicine ,Immunology and Allergy ,education - Abstract
Invasive disease caused by meningococcal capsular groups A, C, W-135, and Y is now preventable by means of glycoconjugate vaccines that target their respective polysaccharide capsules. The capsule of group B meningococci (MenB) is poorly immunogenic and may induce autoimmunity. Vaccines based on the major immunodominant surface porin, PorA, are effective against clonal epidemics but, thus far, have a limited scope of coverage against the wider MenB population at large. In an alternative approach, the first-generation, investigational, recombinant MenB (rMenB) plus outer membrane vesicle (OMV) (rMenB-OMV) vaccine contains a number of relatively conserved surface proteins, fHBP, NHBA (previously GNA2132), and NadA, alongside PorA P1.4-containing OMVs from the New Zealand MeNZB vaccine. MenB currently accounts for approximately 90% of cases of meningococcal disease in England and Wales. To assess potential rMenB-OMV vaccine coverage of pathogenic MenB isolates within this region, all English and Welsh MenB case isolates from January 2008 ( n = 87) were genetically characterized with respect to fHBP, NHBA, NadA, and PorA. Alleles for fHbp , nhba , and porA were identified in all of the isolates, of which 22% were also found to harbor nadA alleles. On the basis of genotypic data and predicted immunological cross-reactivity, the potential level of rMenB-OMV vaccine coverage in England and Wales ranges from 66% to 100%.
- Published
- 2010
38. Characterization of fHbp , nhba ( gna2132 ), nadA , porA , Sequence Type (ST), and Genomic Presence of IS 1301 in Group B Meningococcal ST269 Clonal Complex Isolates from England and Wales
- Author
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Malcolm Guiver, Ray Borrow, Alessandro Muzzi, Philipp Oster, Mariagrazia Pizza, Edward B. Kaczmarski, Maurizio Comanducci, Jay Lucidarme, P. J. Vallely, Elisabeth Kugelberg, Jamie Findlow, Stephen J. Gray, Stefania Bambini, and Christoph M. Tang
- Subjects
Microbiology (medical) ,Molecular epidemiology ,biology ,Sequence analysis ,Neisseria meningitidis ,MeNZB ,Meningococcal vaccine ,Meningococcal disease ,medicine.disease ,biology.organism_classification ,medicine.disease_cause ,Virology ,Microbiology ,medicine ,Neisseriaceae ,Insertion sequence - Abstract
Highly effective glycoconjugate vaccines exist against four of the five major pathogenic groups of meningococci: A, C, W-135, and Y. An equivalent vaccine against group B meningococci (menB) has remained elusive due to the poorly immunogenic capsular polysaccharide. A promising alternative, the investigational recombinant menB (rMenB)- outer membrane vesicle (OMV) vaccine, contains fHBP, NHBA (previously GNA2132), NadA, and outer membrane vesicles (OMVs) from the New Zealand MeNZB vaccine. MenB currently accounts for 90% of meningococcal disease in England and Wales, where the multilocus sequence type (ST) 269 (ST269) clonal complex (cc269) has recently expanded to account for a third of menB cases. To assess the potential cc269 coverage of the rMenB-OMV vaccine, English and Welsh cc269 isolates from the past decade were genetically characterized with respect to fHBP, NHBA, and NadA. All of the isolates harbored fHbp and nhba alleles, while 98% of the cc269 isolates were devoid of nadA . Subvariant profiling of fHbp , nhba , and porA against STs revealed the presence of two broadly distinct and well-defined clusters of isolates, centered around ST269 and ST275, respectively. An additional molecular marker, insertion sequence IS 1301 , was found to be present in 100% and 1301 within the ST269 cluster.
- Published
- 2009
39. Post-transplant lymphoproliferative disorder in adult renal transplant recipients: survival and prognosis
- Author
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Muir Morton, Paul E. Klapper, M. Picton, James Ritchie, Kate Ryan, B. Coupes, P. J. Vallely, Richard J. Byers, and Stephen A Roberts
- Subjects
Cancer Research ,medicine.medical_specialty ,business.industry ,medicine.medical_treatment ,Acute kidney injury ,Immunosuppression ,Hematology ,030230 surgery ,medicine.disease ,Post-transplant lymphoproliferative disorder ,Sepsis ,03 medical and health sciences ,0302 clinical medicine ,Oncology ,030220 oncology & carcinogenesis ,Internal medicine ,Medicine ,Rituximab ,business ,Complication ,Intensive care medicine ,Dialysis ,Kidney transplantation ,medicine.drug - Abstract
Post-transplant lymphoproliferative disorder (PTLD) is a rare, serious complication following solid organ transplantation, with an incidence of 2.6 cases per 1000 patient years. Optimal treatment strategies and risk stratifications specific to kidney transplantation are lacking and PTLD mortality remains high. This study investigated survival and prognosis in 89 cases of PTLD presenting over 44 years at Manchester Royal Infirmary. Patient survival following diagnosis was 72% at 6 months, 67% at 1 year and 54% at 3 years. In multivariate analysis, a poorer 3 year survival was associated with acute kidney injury at diagnosis (p = 0.0001), impaired renal function (p = 0.04), early onset (p = 0.02), T cell disease (p = 0.02) and previous treatment with anti-thymocyte globulin (p = 0.04). The inclusion of graft function adds prognostic value to risk stratification and should be explored further. Strategies to improve survival should include timing and choice of immuno-chemotherapy, preparation for dialysis and aggressive surveillance for sepsis and treatment toxicity.
- Published
- 2015
40. Pan-human coronavirus and human bocavirus SYBR Green and TaqMan PCR assays; use in studying influenza A viruses co-infection and risk of hospitalization
- Author
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P. J. Vallely, K.J. Mutton, Paul E. Klapper, and Edward Goka
- Subjects
Male ,medicine.disease_cause ,Severity of Illness Index ,law.invention ,law ,Human bocavirus ,Odds Ratio ,Influenza A virus ,Child ,Respiratory Tract Infections ,Polymerase chain reaction ,Coronavirus ,Aged, 80 and over ,biology ,Coinfection ,virus diseases ,General Medicine ,Middle Aged ,Co-infection ,Hospitalization ,Infectious Diseases ,Real-time polymerase chain reaction ,Child, Preschool ,Female ,SYBR Green /TaqMan RT-PCR assay ,Coronavirus Infections ,Adult ,Microbiology (medical) ,Influenza A virus, Coronavirus, Bocavirus, SYBR Green/Taqman RT-PCR assay, Co-infection, Hospitalisation ,Adolescent ,Real-Time Polymerase Chain Reaction ,Sensitivity and Specificity ,Virus ,Bocavirus ,Parvoviridae Infections ,Young Adult ,Influenza, Human ,TaqMan ,medicine ,Humans ,Aged ,Original Paper ,Infant ,biology.organism_classification ,medicine.disease ,Virology - Abstract
PURPOSE: Influenza A viruses, human coronaviruses (hCoV) and human bocavirus (hBoV) are emerging respiratory viruses. This study investigated the association between influenza A viruses co-infection with hBoV and hCoV and severity and the sensitivity of a real-time polymerase chain reaction (RT-PCR) assay for identification of 15 coronaviruses. METHODOLOGY: Published sequences for the 15 human coronaviruses were used to design a consensus PCR targeting the replicase open reading frame 1b. A previously published PCR targeting the NS1 Gene of all known human bocavirus strains was also utilized. A series of 217 samples from patients aged 37.7 (SD ± 30.4)] with seasonal influenza A viruses (SeasFluA) identified between 06/2011 and 06/2012 in NW England were tested for hCoV and hBoV using RT-PCR. Association between co-infection and disease outcome was assessed using logistic regression. RESULTS: The limit of detection of hCoV RT-PCR assay was 2 copies/µl of human coronavirus RNA template, a sensitivity comparable to a previously published SYBR green assay for human coronaviruses. A total of 12 hCoV and 17 hBoV were identified in the 217 influenza A positive samples. A higher proportion (61.5%; 8/13) of SeasFluA/hBoV co-infections were identified in patients that were admitted either to a general ward or the intensive care unit compared to 44.3% (66/149) of single SeasFlu A virus infections (OR 2.5 95% CI 0.67-9.34, p = 0.17). In a stratified analysis, there was a trend towards higher association between FluA, hCoV and hBoV with increasing age (especially in patients aged 24-45 years and >65 year old). CONCLUSION: Our hCoV RT-PCR protocol appeared to be of adequate analytical sensitivity for diagnosis. More and larger studies are needed to confirm the role of hCoV, hBoV in causing severe disease when they co-infect with influenza A viruses.
- Published
- 2015
41. Neurological manifestations of human parvovirus B19 infection
- Author
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Jonathan R. Kerr, Graham M. Cleator, Faraj Barah, and P. J. Vallely
- Subjects
viruses ,Erythema Infectiosum ,Arthritis ,Pure red cell aplasia ,Syndrome ,Disease ,Biology ,medicine.disease ,Virus ,Parvoviridae Infections ,Infectious Diseases ,Virology ,Hydrops fetalis ,Immunology ,Parvovirus B19, Human ,Etiology ,medicine ,Humans ,Viral disease ,Nervous System Diseases - Abstract
Since its discovery, human parvovirus B19 has been linked with a broad spectrum of clinical syndromes. An aetiological role for the virus has been confirmed in erythema infectiosum, transient aplastic crisis, persistent infection manifesting as pure red cell aplasia in immunocompromised persons, non-immune hydrops fetalis and arthritis. Less commonly recognised, but receiving increasing attention recently, are the neurological manifestations, a variety of which have been described in patients with either clinically diagnosed or laboratory confirmed B19 infection. The purpose of this review is to summarise present knowledge of B19, its known and potential pathogenic mechanisms and its association with human diseases, particularly those with neurological manifestations. The outcome of the review supports an aetiological role of the virus in neurological disease. However, the pathogenesis remains unknown and elucidating this is a priority. Copyright 2003 John Wiley & Sons, Ltd.
- Published
- 2003
42. Neutralising human recombinant antibodies to human cytomegalovirus glycoproteins gB and gH
- Author
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Foroogh Nejatollahi, James Burnie, Samantha Hodgetts, and P. J. Vallely
- Subjects
Microbiology (medical) ,Immunology ,Immunoglobulin Variable Region ,Enzyme-Linked Immunosorbent Assay ,Antibodies, Viral ,Immunoglobulin light chain ,Sensitivity and Specificity ,Microbiology ,Epitope ,law.invention ,Cytopathogenic Effect, Viral ,Viral Envelope Proteins ,Neutralization Tests ,Peptide Library ,law ,Humans ,Immunology and Allergy ,Cloning, Molecular ,Neutralizing antibody ,Peptide library ,Cells, Cultured ,chemistry.chemical_classification ,biology ,Antibodies, Monoclonal ,General Medicine ,Virology ,Molecular biology ,Recombinant Proteins ,Infectious Diseases ,chemistry ,Cytomegalovirus Infections ,biology.protein ,Recombinant DNA ,Antibody ,Peptides ,Glycoprotein ,Single-Chain Antibodies - Abstract
A phage antibody display library of single chain fragment variable (scFv) was applied to develop anti-HCMV glycoprotein B (gB) and glycoprotein H (gH) neutralising libraries. To enrich for specific scFvs, the phage antibody was panned against cytomegalovirus epitopes derived from the N-terminal part of gB, the C-terminal part of gB and the N-terminal part of gH (NETIYNTTLKYGDV, VTSGSTKD and AASEALDPHAFHLLLNTYGR). A number of clones were differentiated by Bst N1 fingerprinting. After isolation of specific clones against each peptide, the neutralising effect of each clone was assessed by plaque reduction assay. This resulted in the isolation of eight neutralising scFv antibodies with 51-63% neutralising effects. Sequence analysis of three neutralising clones revealed the amino acids specificity changes in heavy and light chains of antibody molecules.
- Published
- 2002
43. Single, dual and multiple respiratory virus infections and risk of hospitalization and mortality
- Author
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Paul E. Klapper, P. J. Vallely, K.J. Mutton, and Edward Goka
- Subjects
Adult ,Male ,medicine.medical_specialty ,Adolescent ,Epidemiology ,medicine.disease_cause ,Virus ,law.invention ,influenza A(H1N1)pdm09 virus ,Young Adult ,law ,Internal medicine ,medicine ,Humans ,Respiratory system ,Child ,Aged ,Aged, 80 and over ,business.industry ,Coinfection ,Infant, Newborn ,single and multiple infections ,Infant ,RSV ,Odds ratio ,Middle Aged ,Intensive care unit ,Original Papers ,Survival Analysis ,parainfluenza virus types 1-3 ,Confidence interval ,respiratory virus infections ,Hospitalization ,Human Parainfluenza Virus ,Cross-Sectional Studies ,Infectious Diseases ,England ,Virus Diseases ,Child, Preschool ,Immunology ,Respiratory virus ,Female ,Rhinovirus ,business - Abstract
SUMMARYRespiratory virus infections cause a significant number of hospitalization and deaths globally. This study investigated the association between single and multiple respiratory virus infections and risk of admission to a general ward, intensive care unit or death in patients aged 0–105 years (mean ± s.d. = 24·4 ± 24·1 years), from North West England, that were tested for respiratory virus infections between January 2007 and June 2012. The majority of infections were in children aged ⩽5 years. Dual or multiple infections occurred in 10·4% (1214/11 715) of patients, whereas single infection occurred in 89·6% (10 501/11 715). Rhinovirus was the most common co-infecting virus (occurring in 69·5%; 844/1214 of co-infections). In a multivariate logistic regression model, multiple infections were associated with an increased risk of admission to a general ward [odds ratio (OR) 1·43, 95% confidence interval (CI) 1·2–1·7,P P P = 0·05, respectively); admitted to an intensive-care unit or dying (OR 1·5, 95% CI 1·20–2·0,P = 0·001 and OR 1·60, 95% CI 1·02–2·40,P = 0·04, respectively). This result emphasizes the importance of RSV, hPIV and mixed infections and calls for research on vaccines, drugs and diagnostic tests targeting these respiratory viruses.
- Published
- 2014
44. Serological diagnosis of varicella–zoster virus in sera with antibody-capture enzyme-linked immunosorbent assay of IgM
- Author
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D.K Oladepo, Paul E. Klapper, P. J. Vallely, and D Percival
- Subjects
Herpesvirus 3, Human ,viruses ,Biotin ,Enzyme-Linked Immunosorbent Assay ,Antibodies, Viral ,medicine.disease_cause ,Herpes Zoster ,Herpesviridae ,Virus ,Serology ,chemistry.chemical_compound ,Chickenpox ,Antibody Specificity ,Virology ,Alphaherpesvirinae ,medicine ,Humans ,Serologic Tests ,Peroxidase ,integumentary system ,biology ,Varicella zoster virus ,virus diseases ,biology.organism_classification ,Immunoglobulin M ,chemistry ,biology.protein ,Viral disease ,Antibody - Abstract
Evaluation was made of three enzyme-linked immunosorbent assay (ELISA) formats; varicella-zoster virus (VZV) indirect ELISA; VZV IgM capture using biotin and VZV IgM capture using peroxidase, for the detection of VZV-specific IgM antibodies in human sera. It was observed that there was no significant difference in sensitivity of detection using the three formats but there were important practical differences in the number of steps and hence time for assay completion between the three assay formats. All assays showed some cross-reactivity with sera containing anti-HSV1 antibodies.
- Published
- 2000
45. Age-related pattern of KI and WU polyomavirus infection
- Author
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C.E. Corless, Paul E. Klapper, B. Abedi Kiasari, P. J. Vallely, and Mohammed Alhammadi
- Subjects
Adult ,Male ,Adolescent ,Human polyomavirus ,Biology ,Polymerase Chain Reaction ,Article ,Age Distribution ,Respiratory infection ,Virology ,Prevalence ,medicine ,Humans ,Respiratory system ,Child ,Respiratory Tract Infections ,Aged ,Polyomavirus Infections ,KI ,WU ,Respiratory tract infections ,Respiratory disease ,Infant, Newborn ,Infant ,Sequence Analysis, DNA ,Middle Aged ,medicine.disease ,Co-infection ,PCR ,Infectious Diseases ,medicine.anatomical_structure ,Upper respiratory tract infection ,Child, Preschool ,Female ,Viral disease ,Polyomavirus ,Respiratory tract - Abstract
Background The role of two recently identified polyomaviruses, KI and WU, in the causation of respiratory disease has not been established. Objectives To determine the prevalence of KI and WU viruses (KIV and WUV) in 371 respiratory samples and evaluate their contribution to respiratory disease. Study Design Specimens were screened for KIV and WUV using single, multiplex or real time PCR; co-infection with other respiratory viruses was evaluated. Results Of the 371 samples analysed, 10 (2.70%) were positive for KIV and 4 (1.08%) were positive for WUV yielding an overall case prevalence of KIV and WUV infection of 3.77%. KIV and WUV were identified in patients aged 45 years (3 patients) with upper respiratory tract infection. Co-infections were found in 5 (50%) and 3 (75%) of the KIV and WUV positive samples, respectively. Conclusions This study supports previous conclusions that KIV and WUV detection in the respiratory tract may be coincidental and reflect reactivation of latent or persistent infection with these viruses. The age distribution of KIV and WUV infection in this study mirrors that found for the other human polyomaviruses, BK and JC.
- Published
- 2008
46. Tumour necrosis factor c2 microsatellite allele is associated with the rate of HIV disease progression
- Author
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Saye Khoo, P. J. Vallely, Ali H. Hajeer, Lynne Pepper, Bibhat K. Mandal, Neil Snowden, William E R Ollier, and Edmund Wilkins
- Subjects
Adult ,Male ,Linkage disequilibrium ,Tumor Necrosis Factor-alpha ,medicine.medical_treatment ,Immunology ,HIV Infections ,Locus (genetics) ,Odds ratio ,Middle Aged ,Biology ,Infectious Diseases ,Cytokine ,Lymphotoxin ,Disease Progression ,medicine ,Humans ,Immunology and Allergy ,Female ,Tumor necrosis factor alpha ,Allele ,Allele frequency ,Alleles ,Microsatellite Repeats - Abstract
BACKGROUND The rate of immunological deterioration and progression to AIDS differs markedly between HIV-positive individuals, and may be influenced by cofactors, HIV phenotype and host T-cell response. Tumour necrosis factor (TNF)-alpha and lymphotoxin stimulate HIV replication and may induce apoptosis of HIV-infected and uninfected lymphocytes in vitro, thus accelerating disease progression and CD4 depletion. Variability in TNF production between individuals is to a degree genetically determined and may be predicted from polymorphisms of microsatellite regions surrounding the human TNF gene locus. METHODS We examined TNf microsatellite polymorphisms in 24 HIV-positive patients with slower disease progression (CD4 count > 400 x 10(6)/l at > or = 6 years), 20 HIV-positive patients with faster progression (CD4 count < 200 x 10(6)/l within 5 years) and 109 healthy controls resident in north-west England. Typing was performed by polymerase chain reaction amplification of TNF a, b, c and d microsatellites and alleles were defined using fluorescence-based semi-automated microsatellite mapping techniques. RESULTS No significant differences in TNF a, b and d allele frequencies were observed between faster and slower progressors, or with healthy controls. The frequency of the TNF c2 allele was significantly different between HIV-positive slower (60.9%) and faster (15%) progressors (P = 0.002) with an odds ratio of 0.1 (95% confidence interval, 0-0.6). TNF c2 was also less frequent in faster progressors than in healthy controls (45.9%, P = 0.006) with an odds ratio of 0.2 (95% confidence interval 0-0.8). CONCLUSIONS This is the first report demonstrating a strong association between the TNF c2 allele and the rate of HIV progression. Although it is possible that this finding may have arisen as a result of linkage disequilibrium with other alleles within the major histocompatibility complex that exert a more powerful effect upon progression, evidence is mounting to suggest that both TNF-alpha and lymphotoxin are closely involved in HIV disease progression and CD4 depletion. Our results serve to highlight the potential importance of genetic polymorphism, particularly of the TNF locus, in influencing the progression of HIV infection.
- Published
- 1997
47. Epidemiology of posttransplantation lymphoproliferative disorder in adult renal transplant recipients
- Author
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Kate Ryan, Paul E. Klapper, M. Picton, Stephen A Roberts, Richard J. Byers, P. J. Vallely, B. Coupes, and Muir Morton
- Subjects
Adult ,Male ,medicine.medical_specialty ,Pathology ,Epstein-Barr Virus Infections ,Herpesvirus 4, Human ,Population ,Comorbidity ,Kaplan-Meier Estimate ,Antibodies, Viral ,Gastroenterology ,Cohort Studies ,Internal medicine ,hemic and lymphatic diseases ,Epidemiology ,Medicine ,Humans ,Epstein-Barr virus ,Postoperative Period ,education ,Survival rate ,Aged ,Retrospective Studies ,education.field_of_study ,Transplantation ,business.industry ,Incidence (epidemiology) ,Incidence ,Lymphoma, Non-Hodgkin ,Retrospective cohort study ,Renal transplantation ,Middle Aged ,medicine.disease ,Hodgkin Disease ,Kidney Transplantation ,Lymphoproliferative Disorders ,United Kingdom ,Lymphoma ,Survival Rate ,surgical procedures, operative ,PTLD ,DNA, Viral ,Female ,business - Abstract
BACKGROUND: There is little information in the literature describing the relationship between posttransplantation lymphoproliferative disorder (PTLD) incidence and presentation with both recipient Epstein-Barr virus (EBV) serostatus and EBV status of PTLD histology, particularly in the late posttransplantation period. METHODS: This study reports the largest UK single-center, single-organ analysis of PTLD to date in a retrospective cohort study of 80 cases occurring in 4189 adult renal transplant recipients. RESULTS: The incidence rate was 2.6 cases per 1000 patient-years (95% confidence interval [95% CI], 2.1-3.2) for PTLD, 1.8 (95% CI, 1.4-2.4) for non-Hodgkin's lymphoma, and 0.2 (95% CI, 0.07-4.2) for Hodgkin's lymphoma. Non-Hodgkin's lymphoma occurred at a rate 7.6 times that of the adult general population in England, whereas the rate for Hodgkin's lymphoma was 5.9 times. The incidence of PTLD was highest during the 10th to 14th posttransplantation years. Early-onset disease was associated with EBV-seronegative recipient status, EBV-positive histology, and the involvement of extranodal sites. PTLD occurring in EBV-seronegative recipients was associated with EBV nuclear antigen antibody deficiency, polymorphic disease, and the involvement of extranodal sites. EBV-negative histology occurred in 32% of cases at a median time to presentation of 109 months. PTLD involving the allograft, central nervous system, and skin was uncommon and occurred late. CONCLUSION: The incidence of PTLD is highest in the late posttransplantation period. Close clinical surveillance and education for transplant recipients is required for the duration of time while immunosuppressed. Failure to detect EBV DNA in blood should not reassure, particularly in patients with symptoms such as abdominal pain, oropharyngeal complaints, neck lumps, and B-symptoms.
- Published
- 2013
48. HIV neutralising antibody delivered by gene therapy with a stable retroviral vector encoded in baculovirus expression systems
- Author
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P. J. Vallely, L. Faqih, Tom Blanchard, E.A. McKenzie, and Paul E. Klapper
- Subjects
0301 basic medicine ,Genetic enhancement ,Neutralising antibody ,Baculovirus expression ,Human immunodeficiency virus (HIV) ,Biology ,medicine.disease_cause ,030226 pharmacology & pharmacy ,Virology ,Viral vector ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Infectious Diseases ,medicine - Published
- 2016
49. Association of acute parvovirus B19 infection with new onset of acute lymphoblastic and myeloblastic leukaemia
- Author
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J Smith, Andrew M. Will, Richard F. Stevens, O B Eden, Jonathan R. Kerr, G M Taylor, P. J. Vallely, Graham M. Cleator, Faraj Barah, Robert Wynn, and V S Cunniffe
- Subjects
Male ,animal diseases ,viruses ,Pathology and Forensic Medicine ,Parvoviridae Infections ,Pathogenesis ,Short Reports ,Leukemia, Megakaryoblastic, Acute ,hemic and lymphatic diseases ,Acute lymphocytic leukemia ,Parvovirus B19, Human ,Null cell ,Humans ,Medicine ,Child ,Interleukin 6 ,Parvoviridae ,biology ,business.industry ,Parvovirus ,virus diseases ,Infant ,hemic and immune systems ,General Medicine ,Precursor Cell Lymphoblastic Leukemia-Lymphoma ,biology.organism_classification ,medicine.disease ,Leukemia ,Child, Preschool ,Acute Disease ,DNA, Viral ,Immunology ,biology.protein ,Cytokines ,Female ,business ,Nested polymerase chain reaction - Abstract
Aims: To investigate the association of acute parvovirus B19 infection with new onset of acute lymphoblastic and myeloblastic leukaemia. Methods: Cerebrospinal fluid (CSF) samples from patients with acute myelogenous leukaemia (AML) at diagnosis (n = 2) and acute lymphoblastic leukaemia (ALL) at diagnosis (n = 14) were analysed for parvovirus B19 DNA by means of nested polymerase chain reaction. In addition, samples from patients with benign intracranial hypertension (BIH) (n = 10) and hydrocephalus (n = 13) were tested as controls. Results: Four leukaemia cases were positive—common ALL (n = 2), null cell ALL (n =1), and M7 AML (n = 1)—whereas all controls were negative (Yates corrected χ2 value, 3.97; p = 0.046; odds ratio, 16.92; confidence interval, 1.03 to 77.18). All four patients were significantly anaemic, but none was encephalitic or had evidence of central nervous system leukaemia. In three of these patients, serum tumour necrosis α, interferon γ, interleukin 6, granulocyte–macrophage colony stimulating factor (range, 34.93–3800.06pg/ml), and macrophage chemoattractant protein 1 were detectable. All of these four patients carried at least one of the HLA-DRB1 alleles, which have been associated with symptomatic parvovirus B19 infection. Conclusion: Erythroid suppression and immune cell proliferation are both associated with B19 infection and may also be important in the pathogenesis of acute leukaemia.
- Published
- 2003
50. Relative quantitation of HIV-1 proviral DNA amplified using the polymerase chain reaction
- Author
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A. A. M. Jiman-Fatani, D. J. Morris, and P. J. Vallely
- Subjects
Microbiology (medical) ,Serial dilution ,Immunology ,virus diseases ,Biology ,Provirus ,Virology ,Molecular biology ,Virus ,law.invention ,chemistry.chemical_compound ,Real-time polymerase chain reaction ,chemistry ,law ,Multiplex polymerase chain reaction ,Quantitative analysis (chemistry) ,DNA ,Polymerase chain reaction - Abstract
A 141-base pair fragment of human immunodeficiency virus-1 (HIV-1) DNA was amplified using the polymerase chain reaction (PCR). The products were slot-blotted onto a nitrocellulose membrane, revealed with a digoxigenin-labelled probe and quantitated by scanning densitometry. This method for the relative quantitation of HIV-1 DNA achieved reliable results and avoided the use of radioisotopes and the electrophoretic transfer of DNA. Testing of serial dilutions of HIV-1 extracted from infected cells revealed smooth titration curves. A reproducible increase in peripheral blood HIV-1 DNA was documented in a haemophilia patient during disease progression.
- Published
- 1994
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