93 results on '"Samuel, C. B."'
Search Results
2. Assessment of a multiplex PCR and Nanopore-based method for dengue virus sequencing in Indonesia
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Samuel C. B. Stubbs, Barbara A. Blacklaws, Benediktus Yohan, Frilasita A. Yudhaputri, Rahma F. Hayati, Brian Schwem, Edsel M. Salvaña, Raul V. Destura, James S. Lester, Khin S. Myint, R. Tedjo Sasmono, and Simon D. W. Frost
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Dengue virus ,Disease surveillance ,Virus sequencing ,Nanopore sequencing ,Infectious and parasitic diseases ,RC109-216 - Abstract
Abstract Background Dengue virus (DENV) infects hundreds of thousands of people annually in Indonesia. However, DENV sequence data from the country are limited, as samples from outbreaks must be shipped across long-distances to suitably equipped laboratories to be sequenced. This approach is time-consuming, expensive, and frequently results in failure due to low viral load or degradation of the RNA genome. Methods We evaluated a method designed to address this challenge, using the ‘Primal Scheme’ multiplex PCR tiling approach to rapidly generate short, overlapping amplicons covering the complete DENV coding-region, and sequencing the amplicons on the portable Nanopore MinION device. The resulting sequence data was assessed in terms of genome coverage, consensus sequence accuracy and by phylogenetic analysis. Results The multiplex approach proved capable of producing near complete coding-region coverage from all samples tested ( x ¯ $$ \overline{x} $$ = 99.96%, n = 18), 61% of which could not be fully amplified using the current, long-amplicon PCR, approach. Nanopore-generated consensus sequences were found to be between 99.17–99.92% identical to those produced by high-coverage Illumina sequencing. Consensus accuracy could be improved by masking regions below 20X coverage depth (99.69–99.92%). However, coding-region coverage was reduced at this depth ( x ¯ $$ \overline{x} $$ = 93.48%). Nanopore and Illumina consensus sequences generated from the same samples formed monophyletic clades on phylogenetic analysis, and Indonesian consensus sequences accurately clustered by geographical origin. Conclusion The multiplex, short-amplicon approach proved superior for amplifying DENV genomes from clinical samples, particularly when the virus was present at low concentrations. The accuracy of Nanopore-generated consensus sequences from these amplicons was sufficient for identifying the geographic origin of the samples, demonstrating that the approach can be a useful tool for identifying and monitoring DENV clades circulating in low-resource settings across Indonesia. However, the inaccuracies in Nanopore-generated consensus sequences mean that the approach may not be appropriate for higher resolution transmission studies, particularly when more accurate sequencing technologies are available.
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- 2020
- Full Text
- View/download PDF
3. Full genomic characterization of a porcine rotavirus strain detected in an asymptomatic piglet in Accra, Ghana
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Samuel C. B. Stubbs, Osbourne Quaye, Maame Ekua Acquah, Samuel Mawuli Adadey, Iain R. L. Kean, Srishti Gupta, and Barbara A. Blacklaws
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Rotavirus A ,Full genome sequence constellation ,Pig ,Porcine ,Ghana ,Veterinary medicine ,SF600-1100 - Abstract
Abstract Background The introduction of rotavirus A vaccination across the developing world has not proved to be as efficacious as first hoped. One cause of vaccine failure may be infection by zoonotic rotaviruses that are very variable antigenically from the vaccine strain. However, there is a lack of genomic information about the circulating rotavirus A strains in farm animals in the developing world that may be a source of infection for humans. We therefore screened farms close to Accra, Ghana for animals sub-clinically infected with rotavirus A and then sequenced the virus found in one of these samples. Results 6.1% of clinically normal cows and pigs tested were found to be Rotavirus A virus antigen positive in the faeces. A subset of these (33.3%) were also positive for virus RNA. The most consistently positive pig sample was taken forward for metagenomic sequencing. This gave full sequence for all open reading frames except segment 5 (NSP1), which is missing a single base at the 5′ end. The virus infecting this pig had genome constellation G5-P[7]-I5-R1-C1-M1-A8-N1-T7-E1-H1, a known porcine genotype constellation. Conclusions Farm animals carry rotavirus A infection sub-clinically at low frequency. Although the rotavirus A genotype discovered here has a pig-like genome constellation, a number of the segments most closely resembled those isolated from humans in suspected cases of zoonotic transmission. Therefore, such viruses may be a source of variable gene segments for re-assortment with other viruses to cause vaccine breakdown. It is recommended that further human and pig strains are characterized in West Africa, to better understand this dynamic.
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- 2020
- Full Text
- View/download PDF
4. Monitoring and Safety Assessment of the Presence of Heavy Metals and Organic Pollutants in Vended Street Foods from Selected Locations in Lagos State Nigeria
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Oyet, G. I., primary and Samuel, C. B., additional
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- 2021
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5. An investig-ation into the epidemiology of chikungunya virus across neglected regions of Indonesia.
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Samuel C B Stubbs, Edison Johar, Frilasita A Yudhaputri, Benediktus Yohan, Marsha S Santoso, Rahma F Hayati, Dionisius Denis, Barbara A Blacklaws, Ann M Powers, R Tedjo Sasmono, Khin Saw Aye Myint, and Simon D W Frost
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Arctic medicine. Tropical medicine ,RC955-962 ,Public aspects of medicine ,RA1-1270 - Abstract
BackgroundChikungunya virus (CHIKV) is an important emerging and re-emerging public health problem worldwide. In Indonesia, where the virus is endemic, epidemiological information from outside of the main islands of Java and Bali is limited.Methodology/principal findingsFour hundred and seventy nine acutely febrile patients presenting between September 2017-2019 were recruited from three city hospitals situated in Ambon, Maluku; Banjarmasin, Kalimantan; and Batam, Batam Island as part of a multi-site observational study. CHIKV RNA was detected in a single serum sample while a separate sample was IgM positive. IgG seroprevalence was also low across all three sites, ranging from 1.4-3.2%. The single RT-PCR positive sample from this study and 24 archived samples collected during other recent outbreaks throughout Indonesia were subjected to complete coding region sequencing to assess the genetic diversity of Indonesian strains. Phylogenetic analysis revealed all to be of a single clade, which was distinct from CHIKV strains recently reported from neighbouring regions including the Philippines and the Pacific Islands.Conclusions/significanceChikungunya virus strains from recent outbreaks across Indonesia all belong to a single clade. However, low-level seroprevalence and molecular detection of CHIKV across the three study sites appears to contrast with the generally high seroprevalences that have been reported for non-outbreak settings in Java and Bali, and may account for the relative lack of CHIKV epidemiological data from other regions of Indonesia.
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- 2020
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6. Distinct Dengue Disease Epidemiology, Clinical, and Diagnosis Features in Western, Central, and Eastern Regions of Indonesia, 2017–2019
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R. Tedjo Sasmono, Marsha S. Santoso, Yanuarni W. B. Pamai, Benediktus Yohan, Anna M. Afida, Dionisius Denis, Ingrid A. Hutagalung, Edison Johar, Rahma F. Hayati, Frilasita A. Yudhaputri, Sotianingsih Haryanto, Samuel C. B. Stubbs, Barbara A. Blacklaws, Khin S. A. Myint, and Simon D. W. Frost
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arbovirus ,dengue ,serotypes ,chikungunya ,clinical ,Indonesia ,Medicine (General) ,R5-920 - Abstract
The people of Indonesia have been afflicted by dengue, a mosquito-borne viral disease, for over 5 decades. The country is the world's largest archipelago with diverse geographic, climatic, and demographic conditions that may impact the dynamics of disease transmissions. A dengue epidemiology study was launched by us to compare and understand the dynamics of dengue and other arboviral diseases in three cities representing western, central, and eastern Indonesia, namely, Batam, Banjarmasin, and Ambon, respectively. A total of 732 febrile patients were recruited with dengue-like illness during September 2017–2019 and an analysis of their demographic, clinical, and virological features was performed. The seasonal patterns of dengue-like illness were found to be different in the three regions. Among all patients, 271 (37.0%) were virologically confirmed dengue, while 152 (20.8%) patients were diagnosed with probable dengue, giving a total number of 423 (57.8%) dengue patients. Patients' age and clinical manifestations also differed between cities. Mostly, mild dengue fever was observed in Batam, while more severe cases were prominent in Ambon. While all dengue virus (DENV) serotypes were detected, distinct serotypes dominated in different locations: DENV-1 in Batam and Ambon, and DENV-3 in Banjarmasin. We also assessed the diagnostic features in the study sites, which revealed different patterns of diagnostic agreements, particularly in Ambon. To detect the possibility of infection with other arboviruses, further testing on 461 DENV RT-PCR-negative samples was performed using pan-flavivirus and -alphavirus RT-PCRs; however, only one chikungunya infection was detected in Ambon. A diverse dengue epidemiology in western, central, and eastern Indonesia was observed, which is likely to be influenced by local geographic, climatic, and demographic conditions, as well as differences in the quality of healthcare providers and facilities. Our study adds a new understanding on dengue epidemiology in Indonesia.
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- 2020
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7. Assessment of a multiplex PCR and Nanopore-based method for dengue virus sequencing in Indonesia
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Stubbs, Samuel C. B., Blacklaws, Barbara A., Yohan, Benediktus, Yudhaputri, Frilasita A., Hayati, Rahma F., Schwem, Brian, Salvaña, Edsel M., Destura, Raul V., Lester, James S., Myint, Khin S., Sasmono, R. Tedjo, and Frost, Simon D. W.
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- 2020
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8. Full genomic characterization of a porcine rotavirus strain detected in an asymptomatic piglet in Accra, Ghana
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Stubbs, Samuel C. B., Quaye, Osbourne, Acquah, Maame Ekua, Adadey, Samuel Mawuli, Kean, Iain R. L., Gupta, Srishti, and Blacklaws, Barbara A.
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- 2020
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9. Phylogenetic Characterization of Crimean-Congo Hemorrhagic Fever Virus Detected in African Blue Ticks Feeding on Cattle in a Ugandan Abattoir
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Eddie M. Wampande, Peter Waiswa, David J. Allen, Roger Hewson, Simon D. W. Frost, and Samuel C. B. Stubbs
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Crimean-Congo hemorrhagic fever virus ,hemorrhagic fever ,viral genomics ,Rhipicephalus (Boophilus) decoloratus ,Rhipicephalus ,ticks ,Biology (General) ,QH301-705.5 - Abstract
Crimean-Congo hemorrhagic fever virus (CCHFV) is the most geographically widespread of the tick-borne viruses. However, African strains of CCHFV are poorly represented in sequence databases. In addition, almost all sequence data collected to date have been obtained from cases of human disease, while information regarding the circulation of the virus in tick and animal reservoirs is severely lacking. Here, we characterize the complete coding region of a novel CCHFV strain, detected in African blue ticks (Rhipicephalus (Boophilus) decoloratus) feeding on cattle in an abattoir in Kampala, Uganda. These cattle originated from a farm in Mbarara, a major cattle-trading hub for much of Uganda. Phylogenetic analysis indicates that the newly sequenced strain belongs to the African genotype II clade, which predominantly contains the sequences of strains isolated from West Africa in the 1950s, and South Africa in the 1980s. Whilst the viral S (nucleoprotein) and L (RNA polymerase) genome segments shared >90% nucleotide similarity with previously reported genotype II strains, the glycoprotein-coding M segment shared only 80% nucleotide similarity with the next most closely related strains, which were derived from ticks in Western India and Northern China. This genome segment also displayed a large number of non-synonymous mutations previously unreported in the genotype II strains. Characterization of this novel strain adds to our limited understanding of the natural diversity of CCHFV circulating in both ticks and in Africa. Such data can be used to inform the design of vaccines and diagnostics, as well as studies exploring the epidemiology and evolution of the virus for the establishment of future CCHFV control strategies.
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- 2021
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10. Molecular epidemiology of dengue in a setting of low reported endemicity: Kupang, East Nusa Tenggara province, Indonesia
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Karolina T Tallo, Joanita Tukan, Tuppak Sirait, Rahma F. Hayati, Marsha S. Santoso, Sotianingsih Haryanto, Dionisius Denis, Samuel C B Stubbs, R. Tedjo Sasmono, Benediktus Yohan, and Simon D. W. Frost
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Serotype ,medicine.medical_specialty ,Veterinary medicine ,Genotype ,Dengue virus ,Biology ,Serogroup ,medicine.disease_cause ,Dengue fever ,Dengue ,Epidemiology ,medicine ,Humans ,Child ,Phylogeny ,Molecular Epidemiology ,Molecular epidemiology ,Incidence (epidemiology) ,Public Health, Environmental and Occupational Health ,General Medicine ,Dengue Virus ,medicine.disease ,Infectious Diseases ,Indonesia ,Parasitology ,Mild fever - Abstract
BackgroundMost regions in Indonesia experience annual dengue epidemics. However, the province of East Nusa Tenggara has consistently reported low incidence. We conducted a dengue molecular epidemiology study in Kupang, the capital of the province.MethodsDengue patients were recruited from May 2016 to September 2017. Dengue virus (DENV) screening was performed using NS1 and immunoglobulin G (IgG)/IgM detection. Serotype was determined using reverse transcription polymerase chain reaction and the envelope genes were sequenced to infer the genetic identity and phylogeny.ResultsFrom 119 patients, dengue was confirmed in 62 (52%). Compared with official data, underreporting of dengue incidence was observed. The majority (36%) of patients were children ConclusionsThe low dengue incidence was most likely caused by sustained local circulation of endemic viruses. This study provides information on the epidemiology of dengue in a low-endemicity setting that should help future mitigation and disease management.
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- 2021
11. Pregnancy and Cardiovascular Disease
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Siu, Samuel C. B., Colman, Jack M., and Rosendorff, Clive, editor
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- 2006
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12. Assessment of a multiplex PCR and Nanopore-based method for dengue virus sequencing in Indonesia
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R. Tedjo Sasmono, Frilasita A. Yudhaputri, Simon D. W. Frost, Raul V. Destura, Khin Saw Aye Myint, James Lester, Samuel C B Stubbs, Edsel Maurice T. Salvana, Benediktus Yohan, B.A. Blacklaws, Brian Schwem, Rahma F. Hayati, Stubbs, Samuel C B [0000-0003-4175-6464], Apollo - University of Cambridge Repository, Stubbs, Samuel CB [0000-0003-4175-6464], and Stubbs, Samuel C. B. [0000-0003-4175-6464]
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0301 basic medicine ,030106 microbiology ,Genome, Viral ,Computational biology ,Biology ,Dengue virus ,Disease Surveillance ,medicine.disease_cause ,lcsh:Infectious and parasitic diseases ,Dengue ,Nanopores ,03 medical and health sciences ,Virology ,Multiplex polymerase chain reaction ,Consensus sequence ,medicine ,Humans ,lcsh:RC109-216 ,Multiplex ,Phylogeny ,Illumina dye sequencing ,Positive-strand RNA viruses ,Research ,Virus Sequencing ,Sequence Analysis, DNA ,Amplicon ,3. Good health ,Nanopore Sequencing ,030104 developmental biology ,Infectious Diseases ,Indonesia ,Minion ,Nanopore sequencing ,Multiplex Polymerase Chain Reaction - Abstract
Background Dengue virus (DENV) infects hundreds of thousands of people annually in Indonesia. However, DENV sequence data from the country are limited, as samples from outbreaks must be shipped across long-distances to suitably equipped laboratories to be sequenced. This approach is time-consuming, expensive, and frequently results in failure due to low viral load or degradation of the RNA genome. Methods We evaluated a method designed to address this challenge, using the ‘Primal Scheme’ multiplex PCR tiling approach to rapidly generate short, overlapping amplicons covering the complete DENV coding-region, and sequencing the amplicons on the portable Nanopore MinION device. The resulting sequence data was assessed in terms of genome coverage, consensus sequence accuracy and by phylogenetic analysis. Results The multiplex approach proved capable of producing near complete coding-region coverage from all samples tested ($$ \overline{x} $$x¯ = 99.96%, n = 18), 61% of which could not be fully amplified using the current, long-amplicon PCR, approach. Nanopore-generated consensus sequences were found to be between 99.17–99.92% identical to those produced by high-coverage Illumina sequencing. Consensus accuracy could be improved by masking regions below 20X coverage depth (99.69–99.92%). However, coding-region coverage was reduced at this depth ($$ \overline{x} $$x¯ = 93.48%). Nanopore and Illumina consensus sequences generated from the same samples formed monophyletic clades on phylogenetic analysis, and Indonesian consensus sequences accurately clustered by geographical origin. Conclusion The multiplex, short-amplicon approach proved superior for amplifying DENV genomes from clinical samples, particularly when the virus was present at low concentrations. The accuracy of Nanopore-generated consensus sequences from these amplicons was sufficient for identifying the geographic origin of the samples, demonstrating that the approach can be a useful tool for identifying and monitoring DENV clades circulating in low-resource settings across Indonesia. However, the inaccuracies in Nanopore-generated consensus sequences mean that the approach may not be appropriate for higher resolution transmission studies, particularly when more accurate sequencing technologies are available.
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- 2020
13. A Control Flow for Transiently Powered Energy Harvesting Sensor Systems
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Oktay Cetinkaya, Geoff V. Merrett, Alberto Rodriguez Arreola, Samuel C. B. Wong, Domenico Balsamo, and Alex S. Weddell
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Control flow ,Computer science ,Reliability (computer networking) ,Real-time computing ,Volume (computing) ,Transient (computer programming) ,Electrical and Electronic Engineering ,Instrumentation ,Energy harvesting ,Energy storage ,Energy (signal processing) ,Power (physics) - Abstract
Transient computing enables application execution to be performed despite power outages. Although it handles the non-deterministic nature of energy harvesting (EH), sensor systems envisioned by the IoT seek more cost- and volume-effective solutions, which are better tailored to application requirements. Additionally, a major drawback of transient computing, keeping track of time, hinders its widespread adoption in the IoT. To overcome these challenges, this paper proposes a control flow for sensor systems by combining two state-of-the-art transient computing schemes in an energy-aware manner, underpinned by a strategy for timekeeping. It enables application execution to be reliably performed even under the most severe EH conditions, with an improved cost and volume efficiency, i.e., smaller energy storage. Benefiting from the combination of the two schemes, dynamic adjustment of system performance is achieved, while the time is accurately tracked. To illustrate the applicability of this flow to actual sensor systems, two case studies: a bicycle trip computer and a step counter, are presented. Empirical results reveal that, even with a tiny amount of energy harvested ( $\simeq$ tens of $\mu \text{J}$ ), our proposed approach can meet application requirements with smaller storage, i.e., 40% and 66% reduction in required capacitance for the presented case studies.
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- 2020
14. Full genomic characterization of a porcine rotavirus strain detected in an asymptomatic piglet in Accra, Ghana
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Srishti Gupta, Samuel Mawuli Adadey, Barbara Blacklaws, Osbourne Quaye, Iain Kean, Samuel C B Stubbs, Maame Ekua Acquah, Quaye, Osbourne [0000-0002-0621-876X], and Apollo - University of Cambridge Repository
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Rotavirus ,Swine ,Porcine ,viruses ,Full genome sequence constellation ,Rotavirus A ,Cattle Diseases ,Genome, Viral ,Biology ,medicine.disease_cause ,Ghana ,Virus ,Rotavirus Infections ,03 medical and health sciences ,Feces ,Virus antigen ,Virology ,Zoonoses ,Genotype ,medicine ,Animals ,Phylogeny ,030304 developmental biology ,Swine Diseases ,0303 health sciences ,NSP1 ,Pig ,lcsh:Veterinary medicine ,General Veterinary ,030306 microbiology ,Transmission (medicine) ,General Medicine ,Vaccination ,RNA, Viral ,lcsh:SF600-1100 ,Cattle ,Vaccine failure ,Research Article - Abstract
Background The introduction of rotavirus A vaccination across the developing world has not proved to be as efficacious as first hoped. One cause of vaccine failure may be infection by zoonotic rotaviruses that are very variable antigenically from the vaccine strain. However, there is a lack of genomic information about the circulating rotavirus A strains in farm animals in the developing world that may be a source of infection for humans. We therefore screened farms close to Accra, Ghana for animals sub-clinically infected with rotavirus A and then sequenced the virus found in one of these samples. Results 6.1% of clinically normal cows and pigs tested were found to be Rotavirus A virus antigen positive in the faeces. A subset of these (33.3%) were also positive for virus RNA. The most consistently positive pig sample was taken forward for metagenomic sequencing. This gave full sequence for all open reading frames except segment 5 (NSP1), which is missing a single base at the 5′ end. The virus infecting this pig had genome constellation G5-P[7]-I5-R1-C1-M1-A8-N1-T7-E1-H1, a known porcine genotype constellation. Conclusions Farm animals carry rotavirus A infection sub-clinically at low frequency. Although the rotavirus A genotype discovered here has a pig-like genome constellation, a number of the segments most closely resembled those isolated from humans in suspected cases of zoonotic transmission. Therefore, such viruses may be a source of variable gene segments for re-assortment with other viruses to cause vaccine breakdown. It is recommended that further human and pig strains are characterized in West Africa, to better understand this dynamic.
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- 2020
15. An investig-ation into the epidemiology of chikungunya virus across neglected regions of Indonesia
- Author
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R. Tedjo Sasmono, Marsha S. Santoso, Ann M. Powers, Simon D. W. Frost, Frilasita A. Yudhaputri, Benediktus Yohan, Rahma F. Hayati, Barbara Blacklaws, Samuel C B Stubbs, Dionisius Denis, Edison Johar, Khin Saw Aye Myint, Stubbs, Samuel CB [0000-0003-4175-6464], Johar, Edison [0000-0002-9491-6487], Yohan, Benediktus [0000-0003-2378-2386], Santoso, Marsha S [0000-0002-1644-6213], Hayati, Rahma F [0000-0002-1627-9187], Denis, Dionisius [0000-0002-2911-9705], Blacklaws, Barbara A [0000-0001-5454-6496], Sasmono, R Tedjo [0000-0003-0986-2590], Myint, Khin Saw Aye [0000-0002-2087-7331], Frost, Simon DW [0000-0002-5207-9879], Apollo - University of Cambridge Repository, Stubbs, Samuel C. B. [0000-0003-4175-6464], Santoso, Marsha S. [0000-0002-1644-6213], Hayati, Rahma F. [0000-0002-1627-9187], Blacklaws, Barbara A. [0000-0001-5454-6496], Sasmono, R. Tedjo [0000-0003-0986-2590], and Frost, Simon D. W. [0000-0002-5207-9879]
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0301 basic medicine ,RNA viruses ,FOS: Computer and information sciences ,Male ,Viral Diseases ,RC955-962 ,Artificial Gene Amplification and Extension ,Monkeys ,medicine.disease_cause ,Pathology and Laboratory Medicine ,Polymerase Chain Reaction ,Disease Outbreaks ,Geographical Locations ,0302 clinical medicine ,Medical Conditions ,Seroepidemiologic Studies ,Arctic medicine. Tropical medicine ,Epidemiology ,Chikungunya ,Clade ,Socioeconomics ,Child ,Phylogeny ,Data Management ,Mammals ,Computer and information sciences ,Eukaryota ,virus diseases ,Phylogenetic Analysis ,Middle Aged ,Indonesian ,Phylogenetics ,Geography ,Infectious Diseases ,Medical Microbiology ,Viral Pathogens ,Child, Preschool ,Viruses ,Vertebrates ,language ,RNA, Viral ,Female ,Public aspects of medicine ,RA1-1270 ,Pathogens ,Chikungunya virus ,Macaque ,Neglected Tropical Diseases ,Research Article ,Primates ,Adult ,medicine.medical_specialty ,Asia ,Adolescent ,Alphaviruses ,030231 tropical medicine ,Oceania ,Microbiology ,Virus ,Togaviruses ,03 medical and health sciences ,Young Adult ,Old World monkeys ,medicine ,Seroprevalence ,Animals ,Humans ,Evolutionary Systematics ,Molecular Biology Techniques ,Microbial Pathogens ,Molecular Biology ,Taxonomy ,Medicine and health sciences ,Genetic diversity ,Evolutionary Biology ,Biology and life sciences ,Public Health, Environmental and Occupational Health ,Organisms ,Outbreak ,Chikungunya Infection ,Infant ,Reverse Transcriptase-Polymerase Chain Reaction ,Tropical Diseases ,language.human_language ,Research and analysis methods ,030104 developmental biology ,Indonesia ,Amniotes ,Chikungunya Fever ,People and places ,Zoology - Abstract
Funder: US-CDC, Background: Chikungunya virus (CHIKV) is an important emerging and re-emerging public health problem worldwide. In Indonesia, where the virus is endemic, epidemiological information from outside of the main islands of Java and Bali is limited. Methodology/Principal Findings: Four hundred and seventy nine acutely febrile patients presenting between September 2017–2019 were recruited from three city hospitals situated in Ambon, Maluku; Banjarmasin, Kalimantan; and Batam, Batam Island as part of a multi-site observational study. CHIKV RNA was detected in a single serum sample while a separate sample was IgM positive. IgG seroprevalence was also low across all three sites, ranging from 1.4–3.2%. The single RT-PCR positive sample from this study and 24 archived samples collected during other recent outbreaks throughout Indonesia were subjected to complete coding region sequencing to assess the genetic diversity of Indonesian strains. Phylogenetic analysis revealed all to be of a single clade, which was distinct from CHIKV strains recently reported from neighbouring regions including the Philippines and the Pacific Islands. Conclusions/Significance: Chikungunya virus strains from recent outbreaks across Indonesia all belong to a single clade. However, low-level seroprevalence and molecular detection of CHIKV across the three study sites appears to contrast with the generally high seroprevalences that have been reported for non-outbreak settings in Java and Bali, and may account for the relative lack of CHIKV epidemiological data from other regions of Indonesia.
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- 2020
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16. Emergent design challenges for embedded systems and paths forward
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Samuel C. B. Wong, Yinyuan Zhao, Martin Decky, Siva Satyendra Sahoo, Amit Kumar Singh, Xiaohang Wang, Jiachen Wang, Geoff V. Merrett, and Akash Kumar
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Mixed criticality ,Cover (telecommunications) ,Computer science ,Application domain ,business.industry ,Energy (esotericism) ,Reliability (computer networking) ,Embedded system ,Systems design ,Emergent Design ,business ,Efficient energy use - Abstract
Modern embedded systems need to cater for several needs depending upon the application domain in which they are deployed. For example, mixed-critically needs to be considered for real-time and safety-critical systems and energy for battery-operated systems. At the same time, many of these systems demand for their reliability and security as well. With electronic systems being used for increasingly varying type of applications, novel challenges have emerged. For example, with the use of embedded systems in increasingly complex applications that execute tasks with varying priorities, mixed-criticality systems present unique challenges to designing reliable systems. The large design space involved in implementing cross-layer reliability in heterogeneous systems, particularly for mixed-critical systems, poses new research problems. Further, malicious security attacks on these systems pose additional extraordinary challenges in the system design. In this paper, we cover both the industry and academia perspectives of the challenges posed by these emergent aspects of system design towards designing high-performance, energy-efficient, reliable and/or secure embedded systems. We also provide our views on paths forward.
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- 2021
17. Patterns of the fecal microbiota in the Juan Fernández fur seal (Arctocephalus philippii)
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Samuel C B Stubbs, Barbara Blacklaws, Constanza Toro-Valdivieso, Frederick Toro, Eduardo Castro-Nallar, Toro-Valdivieso, Constanza [0000-0002-4485-5196], and Apollo - University of Cambridge Repository
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DNA, Bacterial ,Firmicutes ,Zoology ,microbiome ,Microbiology ,Fusobacteria ,Actinobacteria ,Feces ,RNA, Ribosomal, 16S ,Proteobacteria ,Animals ,Microbiome ,scatology ,Chile ,marine mammals ,biology ,Bacteria ,Bacteroidetes ,Fur Seals ,Microbiota ,Original Articles ,Biodiversity ,Sequence Analysis, DNA ,Arctocephalus philippii ,biology.organism_classification ,QR1-502 ,Gastrointestinal Microbiome ,pinnipeds ,Arctophoca philippii ,Original Article ,Fur seal - Abstract
As apex predators, pinnipeds are considered to be useful bioindicators of marine and coastal environments. Endemic to a small archipelago in the South Pacific, the Juan Fernandez fur seal (JFFS) is one of the less‐studied members of the pinniped family Otariidae. This study aimed to characterize the fecal microbiome of the JFFS for the first time, to establish a baseline for future studies of host–microbial–environment interactions and monitoring programs. During two consecutive reproductive seasons, 57 fecal samples were collected from seven different JFFS colonies within the Juan Fernandez Archipelago, Chile. Bacterial composition and abundance were characterized by sequencing the V4 region of the 16S rRNA gene. The overall microbiome composition was dominated by five phyla: Firmicutes (40% ±24), Fusobacteria (30% ±17), Bacteroidetes (22% ±10), Proteobacteria (6% ±4), and Actinobacteria (2% ±3). Alpha diversity was higher in Tierras Blancas. However, location was not found to be a dominant driver of microbial composition. Interestingly, the strongest signal in the data was a negative association between the genera Peptoclostridium and Fusobacterium, which explained 29.7% of the total microbial composition variability between samples. The genus Peptoclostridium has not been reported in other pinniped studies, and its role here is unclear, with interpretation challenging due to a lack of information regarding microbiome functionality in marine mammals. As a first insight into the JFFS fecal microbiome, these results contribute towards our understanding of the natural microbial diversity and composition in free‐ranging pinnipeds., Two distinct microbial patterns were identified in Juan Fernandez fur seal fecal samples. We suspect that sex, age, and especially diet are most likely to be influencing the observed patterns.
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- 2021
18. Emergent design challenges for embedded systems and paths forward
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Sahoo, Siva Satyendra, primary, Kumar, Akash, additional, Decky, Martin, additional, Wong, Samuel C. B., additional, Merrett, Geoff V., additional, Zhao, Yinyuan, additional, Wang, Jiachen, additional, Wang, Xiaohang, additional, and Singh, Amit Kumar, additional
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- 2021
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19. Molecular epidemiology of dengue in a setting of low reported endemicity: Kupang, East Nusa Tenggara province, Indonesia
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Hayati, Rahma F, primary, Denis, Dionisius, additional, Tallo, Karolina T, additional, Sirait, Tuppak, additional, Tukan, Joanita, additional, Santoso, Marsha S, additional, Yohan, Benediktus, additional, Haryanto, Sotianingsih, additional, Frost, Simon D W, additional, Stubbs, Samuel C B, additional, and Sasmono, R Tedjo, additional
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- 2021
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20. The complete mitochondrial genome of
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Stefan P. W. de Vries, Silke A. Riesle-Sbarbaro, Samuel C B Stubbs, James L. N. Wood, Kofi Amponsah-Mensah, Andrew A. Cunnigham, and David R. Sargan
- Subjects
0106 biological sciences ,0301 basic medicine ,Genetics ,Mitochondrial DNA ,Phylogenetic tree ,biology ,mitogenome ,Epomophorus gambianus ,biology.organism_classification ,phylogeny ,010603 evolutionary biology ,01 natural sciences ,Pteropodidae ,03 medical and health sciences ,030104 developmental biology ,Phylogenetics ,GenBank ,Chiroptera ,Transfer RNA ,Molecular Biology ,Gene ,Mitogenome Announcement ,Research Article - Abstract
The Gambian epauletted fruit bat, Epomophorus gambianus, is widely distributed across sub-Saharan Africa. Its assembled and annotated mitochondrial genome (GenBank accession no. KT963027) is 16,702 bases in length, containing 13 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes and two non-coding regions: the control region (D-loop) and the origin of light-strand replication (OL). The average base composition is 32.2% A; 27.6% C; 14% G; and 26.1% T. The mitogenome presented a structural composition greatly conserved between members of the Pteropodidae family.
- Published
- 2021
21. Energy-aware HW/SW Co-modeling of Batteryless Wireless Sensor Nodes
- Author
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Alex S. Weddell, William Wang, Samuel C. B. Wong, Sivert T. Sliper, Geoff V. Merrett, and Stephanie Gauthier
- Subjects
Power management ,business.industry ,Computer science ,Instruction set ,Microcontroller ,SystemC ,Embedded system ,Wireless ,business ,computer ,Energy harvesting ,Energy (signal processing) ,Virtual prototyping ,computer.programming_language - Abstract
Energy harvesting wireless sensor nodes are sensitive to spatial and temporal fluctuations in energy availability. This issue is especially prevalent in batteryless systems, where devices are directly connected to power sources with little or no buffering. The strong coupling of energy supply and demand introduces a new dimension to the problem of designing robust networked sensing systems. We propose a modeling framework for this class of batteryless systems with an emphasis on the interactions between energy and function. The tool models energy harvesters, power management circuitry, energy storage, microcontrollers, sensors, radio modules, environmental models, and is fully extensible. The microcontroller model is based on cycle-accurate instruction set simulators from Fused, with various peripheral extensions to enable board-level functionality, such as SPI, DMA, hardware multiplier etc. The tool enables virtual prototyping of self-powered wireless sensor nodes, but is especially useful for studying intermittent operation and developing application specific software, hardware, or combined solutions. The simulator is capable of executing real workloads under realistic conditions and this is demonstrated through a case study where the same compiled binary is executed on a virtual prototype and its corresponding physical wireless sensor system to yield matching digital traces and current profiles
- Published
- 2020
22. Stability Evaluation of Candidate Precursors for Chemical Vapor Deposition of Hafnium Diboride (HfB2)
- Author
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Rimsza, Jessica M., primary, Chackerian, Samuel C. B., additional, Boyle, Timothy J., additional, and Hernandez-Sanchez, Bernadette A., additional
- Published
- 2021
- Full Text
- View/download PDF
23. Phylogenetic Characterization of Crimean-Congo Hemorrhagic Fever Virus Detected in African Blue Ticks Feeding on Cattle in a Ugandan Abattoir
- Author
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Wampande, Eddie M., primary, Waiswa, Peter, additional, Allen, David J., additional, Hewson, Roger, additional, Frost, Simon D. W., additional, and Stubbs, Samuel C. B., additional
- Published
- 2021
- Full Text
- View/download PDF
24. Distinct Dengue Disease Epidemiology, Clinical, and Diagnosis Features in Western, Central, and Eastern Regions of Indonesia, 2017-2019
- Author
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Edison Johar, Rahma F. Hayati, Barbara Blacklaws, Simon D. W. Frost, Samuel C B Stubbs, Ingrid A Hutagalung, Benediktus Yohan, Khin Saw Aye Myint, Yanuarni W B Pamai, Dionisius Denis, Anna Matiana Afida, Frilasita A. Yudhaputri, R. Tedjo Sasmono, Sotianingsih Haryanto, Marsha S. Santoso, Blacklaws, Barbara [0000-0001-5454-6496], and Apollo - University of Cambridge Repository
- Subjects
Serotype ,medicine.medical_specialty ,chikungunya ,Disease ,Dengue virus ,medicine.disease_cause ,Arbovirus ,clinical ,Dengue fever ,Environmental health ,Epidemiology ,medicine ,Chikungunya ,Original Research ,lcsh:R5-920 ,virus diseases ,General Medicine ,medicine.disease ,dengue ,Geography ,arbovirus ,serotypes ,Indonesia ,Medicine ,Viral disease ,lcsh:Medicine (General) - Abstract
The people of Indonesia have been afflicted by dengue, a mosquito-borne viral disease, for over 5 decades. The country is the world's largest archipelago with diverse geographic, climatic, and demographic conditions that may impact the dynamics of disease transmissions. A dengue epidemiology study was launched by us to compare and understand the dynamics of dengue and other arboviral diseases in three cities representing western, central, and eastern Indonesia, namely, Batam, Banjarmasin, and Ambon, respectively. A total of 732 febrile patients were recruited with dengue-like illness during September 2017–2019 and an analysis of their demographic, clinical, and virological features was performed. The seasonal patterns of dengue-like illness were found to be different in the three regions. Among all patients, 271 (37.0%) were virologically confirmed dengue, while 152 (20.8%) patients were diagnosed with probable dengue, giving a total number of 423 (57.8%) dengue patients. Patients' age and clinical manifestations also differed between cities. Mostly, mild dengue fever was observed in Batam, while more severe cases were prominent in Ambon. While all dengue virus (DENV) serotypes were detected, distinct serotypes dominated in different locations: DENV-1 in Batam and Ambon, and DENV-3 in Banjarmasin. We also assessed the diagnostic features in the study sites, which revealed different patterns of diagnostic agreements, particularly in Ambon. To detect the possibility of infection with other arboviruses, further testing on 461 DENV RT-PCR-negative samples was performed using pan-flavivirus and -alphavirus RT-PCRs; however, only one chikungunya infection was detected in Ambon. A diverse dengue epidemiology in western, central, and eastern Indonesia was observed, which is likely to be influenced by local geographic, climatic, and demographic conditions, as well as differences in the quality of healthcare providers and facilities. Our study adds a new understanding on dengue epidemiology in Indonesia.
- Published
- 2020
25. An investig-ation into the epidemiology of chikungunya virus across neglected regions of Indonesia
- Author
-
Stubbs, Samuel C. B., primary, Johar, Edison, additional, Yudhaputri, Frilasita A., additional, Yohan, Benediktus, additional, Santoso, Marsha S., additional, Hayati, Rahma F., additional, Denis, Dionisius, additional, Blacklaws, Barbara A., additional, Powers, Ann M., additional, Sasmono, R. Tedjo, additional, Myint, Khin Saw Aye, additional, and Frost, Simon D. W., additional
- Published
- 2020
- Full Text
- View/download PDF
26. Distinct Dengue Disease Epidemiology, Clinical, and Diagnosis Features in Western, Central, and Eastern Regions of Indonesia, 2017–2019
- Author
-
Sasmono, R. Tedjo, primary, Santoso, Marsha S., additional, Pamai, Yanuarni W. B., additional, Yohan, Benediktus, additional, Afida, Anna M., additional, Denis, Dionisius, additional, Hutagalung, Ingrid A., additional, Johar, Edison, additional, Hayati, Rahma F., additional, Yudhaputri, Frilasita A., additional, Haryanto, Sotianingsih, additional, Stubbs, Samuel C. B., additional, Blacklaws, Barbara A., additional, Myint, Khin S. A., additional, and Frost, Simon D. W., additional
- Published
- 2020
- Full Text
- View/download PDF
27. A Control Flow for Transiently Powered Energy Harvesting Sensor Systems
- Author
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Balsamo, Domenico, primary, Cetinkaya, Oktay, additional, Arreola, Alberto Rodriguez, additional, Wong, Samuel C. B., additional, Merrett, Geoff V., additional, and Weddell, Alex S., additional
- Published
- 2020
- Full Text
- View/download PDF
28. Safety Assessment of the Presence of Heavy Metals and Organic Pollutants in Vended Street Foods from Selected Locations in Lagos State Nigeria
- Author
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Oyet, G. I., primary and Samuel, C. B., primary
- Published
- 2020
- Full Text
- View/download PDF
29. A Nanopore-based method for generating complete coding region sequences of dengue virus in resource-limited settings
- Author
-
Frilasita A. Yudhaputri, Benediktus Yohan, R. Tedjo Sasmono, Raul V. Destura, Edsel Maurice T. Salvana, Brian Schwem, Simon D. W. Frost, B.A. Blacklaws, Samuel C B Stubbs, and Khin Saw Aye Myint
- Subjects
Computer science ,viruses ,virus diseases ,Computational biology ,biochemical phenomena, metabolism, and nutrition ,Amplicon ,Dengue virus ,medicine.disease_cause ,Nanopore ,Minion ,Multiplex polymerase chain reaction ,Consensus sequence ,medicine ,Coding region ,Multiplex ,Nanopore sequencing ,Primer (molecular biology) - Abstract
Dengue virus (DENV) sequencing is a vital tool for surveillance and epidemiology studies. However, the current methods employed for sequencing DENV are expensive, laborious and technically demanding, often due to intra- and inter-serotype variability. Therefore, on-site DENV sequencing is not feasible in many of the areas where DENV is endemic. Surveillance in these areas can only be performed by shipping samples to well-equipped central laboratories for sequencing. However, long periods of inadequate storage and unreliable shipping conditions mean that such samples can arrive degraded, rendering sequence recovery difficult. We therefore aimed to develop an approach that is simple, portable and effective, to be used for on-site DENV sequencing in limited resource settings.To achieve this, we first used the ‘Primal Scheme’ primer design tool to develop a simple and robust protocol for generating multiple short amplicons, covering the complete coding-region of DENV isolates. We then paired this method with the Nanopore MinION, a portable and affordable sequencing device, well-suited to minimal resource settings.The multiplex PCR method produced full-coding-region coverage of all DENV samples tested with no optimisation required, and Nanopore sequencing of the short amplicons generated consensus sequences with high accuracy (99.52 - 99.92 %). Phylogenetic analysis of the consensus sequences generated using the new method showed that they formed monophyletic clusters with those produced by the current, long-amplicon, Illumina method, thus demonstrating that the two approaches are comparable. The multiplex method’s simplicity and portability compared to the current DENV sequencing approach make it well-suited for use in resource-limited, DENV-endemic regions. Deployment of the method in these regions would increase the capacity for DENV surveillance and has the potential to provide vital resolution for future DENV epidemiology studies.
- Published
- 2018
30. The Plasma Virome Post-Kidney Transplantation Predicts Clinical Outcome
- Author
-
Simon D. W. Frost, Samuel C B Stubbs, James Lester, Limy Wong, Elaine C. Jolly, Paul A. Lyons, Kenneth G. C. Smith, and Jonathan L. Heeney
- Subjects
medicine.medical_specialty ,Viral reactivation ,business.industry ,medicine.medical_treatment ,Immunosuppression ,medicine.disease ,Transplantation ,Clinical research ,Internal medicine ,Medicine ,Human virome ,In patient ,business ,Viral load ,Kidney transplantation - Abstract
Background: Long-term immunosuppression following solid organ transplantation is associated with increased morbidity and mortality. Viral infections as a result of immunosuppression are a major cause of prolonged hospitalization and poor prognostic outcome post-transplantation. Additionally, changes in the viral populations inhabiting these patients (the virome) may affect the immune response, with implications for graft survival. Methods: We performed metagenomic sequencing of RNA and DNA extracted from paired plasma samples taken from patients pre- and post-renal transplant. This untargeted approach was used to detect changes in the virome following immunosuppression and to determine viral targets for further characterisation. Correlations between viral presence, viral load and clinical outcome were established to determine the relevance of these viruses to patient outcomes. Findings: Anellovirus load was found to be a strong predictor of immunosuppression-related infectious complications, especially viral reactivation events, in the first year post-transplant. Anellovirus load was increased in patients who had been treated for acute graft rejection 1-2 months prior to sampling, revealing additional immunosuppressive measures can have a prolonged negative impact on a patient. Interpretation: Currently no assays exist for predicting infection risk in immunosuppressed patients, meaning that potentially life-threatening infections must be dealt with retrospectively. Our observations support the possibility of a viral marker being used to monitor immunosuppressive protocols, pre-emptively minimizing risk of severe infections including viral re-activation events, reducing hospitalization and improving long-term allotransplant success rates. Funding Statement: This work was funded by Wellcome Programme Grant number WT091501/Z/10/Z, which provided funding for sequencing, reagents and computing infrastructure. MRC programme grant number MR/L019027/1 provided funding for collection of the samples. MRC CASE Studentship MR/K017071/1 provided funding for reagents and the PhD studentship of SS, of which this study formed a part. LW is funded by a Wellcome Clinical Training Fellowship and ECJ received funding from an MRC Clinical Research Fellowship, Sackler Studentship and Evelyn Trust funding. Declaration of Interests: SS reports an MRC CASE studentship in collaboration with GlaxoSmithKline, outside of the submitted work. GSK did not influence any aspect of this study including data collection, analysis, writing of the manuscript or decision to submit for publication. All other authors have nothing to disclose. Ethics Approval Statement: All samples were anonymized and obtained with informed written consent under the approval of the Cambridge Local Research Ethical Committee (reference 08/H0308/176).
- Published
- 2018
31. Detection and seroprevalence of morbillivirus and other paramyxoviruses in geriatric cats with and without evidence of azotemic chronic kidney disease
- Author
-
Laurence Tiley, Nicholas Hope, Ian Mickleburgh, Katie E McCallum, Tim Williams, Dave Dight, and Samuel C B Stubbs
- Subjects
0301 basic medicine ,Male ,medicine.medical_specialty ,040301 veterinary sciences ,Urinary system ,Standard Article ,Cat Diseases ,Gastroenterology ,Virus ,0403 veterinary science ,azotemia ,03 medical and health sciences ,paramyxovirus ,Morbillivirus ,Seroepidemiologic Studies ,Internal medicine ,medicine ,Seroprevalence ,Animals ,Nephrology/Urology ,Renal Insufficiency, Chronic ,feline ,Retrospective Studies ,CATS ,Paramyxoviridae Infections ,General Veterinary ,biology ,business.industry ,Reverse Transcriptase Polymerase Chain Reaction ,Case-control study ,04 agricultural and veterinary sciences ,biology.organism_classification ,medicine.disease ,United Kingdom ,Standard Articles ,morbillivirus ,030104 developmental biology ,Cross-Sectional Studies ,Case-Control Studies ,Paramyxoviridae ,Cats ,Female ,Azotemia ,SMALL ANIMAL ,business ,Morbillivirus Infections ,Kidney disease - Abstract
Feline morbillivirus (FeMV) is associated with the presence of tubulo-interstitial nephritis (TIN) in cats, however the seroprevalence of FeMV in the UK and the association between the presence of FeMV and renal azotemia is unknown HYPOTHESIS/OBJECTIVES: To identify whether paramyxoviruses are present in urine samples of geriatric cats and to develop an assay to assess FeMV seroprevalence. To investigate the relationship between both urinary paramyxovirus (including FeMV) excretion and FeMV seroprevalence and azotemic chronic kidney disease (CKD). Seventy-nine cats (40 for FeMV detection; 72 for seroprevalence). Retrospective cross-sectional, case control study. Viral RNA was extracted from urine for RT-PCR. PCR products were sequenced for virus identification and comparison. The FeMV N protein gene was cloned and partially purified for use as an antigen to screen cat sera for anti-FeMV antibodies by Western Blot. Feline morbillivirus RNA from five distinct morbilliviruses were identified. Detection was not significantly different between azotemic CKD (1/16) and nonazotemic groups (4/24; P = .36). Three distinct, non-FeMV paramyxoviruses were present in the nonazotemic group but their absence from the azotemic group was not statistically significant (P = .15). 6/14 (43%) azotemic cats and 40/55 (73%) nonazotemic cats were seropositive (P = .06). Feline morbillivirus was detected in cats in the UK for the First time. However, there was no association between virus prevalence or seropositivity and azotemic CKD. These data do not support the hypothesis that FeMV infection is associated with the development of azotemic CKD in cats in the UK. [Abstract copyright: © 2018 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.]
- Published
- 2017
32. Self-Rated Imagery and Vividness of Task Pictures in Relation to Visual Memory
- Author
-
Berger, Goran H. and Gaunitz, Samuel C. B.
- Abstract
Marks (1973) and Gur & Hilgard (1975) have reported success in predicting performance in visual-memory tasks from scores in a questionnare of self-rated vividness of imagery, i.e. the Vividness of Visual Imagery Questionnaire (VVIQ; Marks, 1973). These findings were disconfirmed in two experiments in which the VVIQ was used and vivid pictures were presented in memory tasks. (Editor/RK)
- Published
- 1977
33. Institutional Development for Theological Education in the Two-thirds World: Summary of findings of the 1995 consultation at the Oxford Centre for Mission Studies
- Author
-
Paredes, Tito, Samuel, Vinay, Samuel, Colleen, Angel, Gervais, Bennett, John, Callanta, Ruth, Beer, Fiona, Kovats, George, Ferguson, Steven, Hardy, Steve, Voth, Steven, Lumby, Simon, Brouwer, Kent, Bediako, Kwame, Samuel, C B, Samuel, David, Kemp, Roger, Zokue, Isaac, Gatimu, Karinga, Sendek, Elizabeth, and Calheiros, Izes
- Published
- 1995
34. EVANGELISM IN SOCIAL ACTION MINISTRIES
- Author
-
Samuel, C. B.
- Published
- 1990
35. Validation of a high-throughput real-time polymerase chain reaction assay for the detection of capripoxviral DNA
- Author
-
Eeva S.M. Tuppurainen, Mark Henstock, C.A.L. Oura, Timothy R. Bowden, Samuel C B Stubbs, and Donald P. King
- Subjects
Veterinary Medicine ,Cattle Diseases ,Sheep Diseases ,Poxviridae Infections ,Biology ,Real-Time Polymerase Chain Reaction ,Sensitivity and Specificity ,Capripoxvirus ,Automation ,chemistry.chemical_compound ,Virology ,Animals ,Orthopoxvirus ,Goat Diseases ,Sheep ,Goats ,biology.organism_classification ,DNA extraction ,High-Throughput Screening Assays ,Real-time polymerase chain reaction ,chemistry ,DNA, Viral ,Nucleic acid ,Parapoxvirus ,Cattle ,REAL-TIME POLYMERASE CHAIN REACTION ASSAY ,DNA - Abstract
Capripoxviruses, which are endemic in much of Africa and Asia, are the aetiological agents of economically devastating poxviral diseases in cattle, sheep and goats. The aim of this study was to validate a high-throughput real-time PCR assay for routine diagnostic use in a capripoxvirus reference laboratory. The performance of two previously published real-time PCR methods were compared using commercially available reagents including the amplification kits recommended in the original publication. Furthermore, both manual and robotic extraction methods used to prepare template nucleic acid were evaluated using samples collected from experimentally infected animals. The optimised assay had an analytical sensitivity of at least 63 target DNA copies per reaction, displayed a greater diagnostic sensitivity compared to conventional gel-based PCR, detected capripoxviruses isolated from outbreaks around the world and did not amplify DNA from related viruses in the genera Orthopoxvirus or Parapoxvirus. The high-throughput robotic DNA extraction procedure did not adversely affect the sensitivity of the assay compared to manual preparation of PCR templates. This laboratory-based assay provides a rapid and robust method to detect capripoxviruses following suspicion of disease in endemic or disease-free countries.
- Published
- 2012
36. TWENTY YEAR TRENDS IN MATERNAL AND PERINATAL COMPLICATIONS IN PREGNANT WOMEN WITH HEART DISEASE
- Author
-
Jack M. Colman, Mathew Sermer, Jennifer Mason, Samuel C. B. Siu, Candice K. Silversides, and Rachel M. Wald
- Subjects
Pediatrics ,medicine.medical_specialty ,education.field_of_study ,Increased risk ,Heart disease ,business.industry ,Perinatal complications ,Population ,Medicine ,Cardiology and Cardiovascular Medicine ,business ,medicine.disease ,education - Abstract
Background: Pregnant women with heart disease are at increased risk of complications. At our centre, management algorithms for this population have been implemented since 2001. However, the impact of standardized care on outcomes has not been evaluated. Methods: We prospectively recorded baseline
- Published
- 2017
37. A viral discovery methodology for clinical biopsy samples utilising massively parallel next generation sequencing
- Author
-
Gordon M. Daly, Anne L. Palser, Laurence Tiley, Nick Bexfield, Graeme J.M. Alexander, Jonathan L. Heeney, Antonia P. Mayer, William Bernal, Nizar Drou, Mario Caccamo, Paul Kellam, Judith Heaney, and Samuel C B Stubbs
- Subjects
Viral Diseases ,General Science & Technology ,Biopsy ,viruses ,Sequence assembly ,lcsh:Medicine ,Biology ,Microbiology ,Virus ,DNA sequencing ,Transcriptomes ,03 medical and health sciences ,Dogs ,Genome Analysis Tools ,Virology ,Emerging Viral Diseases ,MD Multidisciplinary ,medicine ,Animals ,Humans ,Genome Sequencing ,lcsh:Science ,Massively parallel ,030304 developmental biology ,0303 health sciences ,Multidisciplinary ,Contig ,Human liver ,medicine.diagnostic_test ,030306 microbiology ,lcsh:R ,Computational Biology ,food and beverages ,Genomics ,3. Good health ,Viral Disease Diagnosis ,Infectious Diseases ,Liver ,Viruses ,Medicine ,RNA, Viral ,lcsh:Q ,RNA extraction ,Research Article - Abstract
Here we describe a virus discovery protocol for a range of different virus genera, that can be applied to biopsy-sized tissue samples. Our viral enrichment procedure, validated using canine and human liver samples, significantly improves viral read copy number and increases the length of viral contigs that can be generated by de novo assembly. This in turn enables the Illumina next generation sequencing (NGS) platform to be used as an effective tool for viral discovery from tissue samples.
- Published
- 2011
38. Pregnancy and Cardiovascular Disease
- Author
-
Samuel C. B. Siu and Jack M. Colman
- Subjects
medicine.medical_specialty ,Pregnancy ,Cardiac output ,business.industry ,Hemodynamics ,Blood volume ,medicine.disease ,medicine.anatomical_structure ,Blood pressure ,Internal medicine ,Vascular resistance ,medicine ,Intravascular volume status ,Cardiology ,business ,Autotransfusion - Abstract
During pregnancy, hormonally mediated changes in blood volume, red cell mass, and heart rate result in a 50% increase in intravascular volume and cardiac output, peaking during the second trimester and remaining constant through the remainder of the pregnancy (1). Gestational hormones, circulating prostaglandins, and the low-resistance vascular bed in the placenta result in concomitant decreases in peripheral vascular resistance and blood pressure. During labor and delivery, pain and uterine contractions result in additional increases in cardiac output and blood pressure. Immediately following delivery, relief of caval compression and autotransfusion from the emptied and contracted uterus produce a further increase in cardiac output. The hemodynamic changes of pregnancy persist for at least several days postpartum and may not fully resolve until the sixth postpartum month.
- Published
- 2007
39. Pregnancy and Cardiovascular Disease
- Author
-
Siu, Samuel C. B., primary and Colman, Jack M., additional
- Full Text
- View/download PDF
40. India's Socioeconomic Context
- Author
-
Samuel, C. B., primary
- Published
- 2003
- Full Text
- View/download PDF
41. Pregnancy and Cardiovascular Disease.
- Author
-
Rosendorff, Clive, Siu, Samuel C. B., and Colman, Jack M.
- Abstract
During pregnancy, hormonally mediated changes in blood volume, red cell mass, and heart rate result in a 50% increase in intravascular volume and cardiac output, peaking during the second trimester and remaining constant through the remainder of the pregnancy (1). Gestational hormones, circulating prostaglandins, and the low-resistance vascular bed in the placenta result in concomitant decreases in peripheral vascular resistance and blood pressure. During labor and delivery, pain and uterine contractions result in additional increases in cardiac output and blood pressure. Immediately following delivery, relief of caval compression and autotransfusion from the emptied and contracted uterus produce a further increase in cardiac output. The hemodynamic changes of pregnancy persist for at least several days postpartum and may not fully resolve until the sixth postpartum month. [ABSTRACT FROM AUTHOR]
- Published
- 2006
- Full Text
- View/download PDF
42. Building A Nation
- Author
-
Samuel, C. B., primary
- Published
- 1999
- Full Text
- View/download PDF
43. Issues and challenges for Christian NGOs in the India of the twenty-first century
- Author
-
Samuel, C. B., primary
- Published
- 1996
- Full Text
- View/download PDF
44. Prayer and Social Transformation
- Author
-
Samuel, C. B., primary
- Published
- 1996
- Full Text
- View/download PDF
45. Guide-lines for Preparation of Case Studies
- Author
-
Samuel, C. B., primary
- Published
- 1990
- Full Text
- View/download PDF
46. India's Socioeconomic Context: Challenges and opportunities.
- Author
-
Samuel, C. B.
- Subjects
- *
POVERTY , *EDUCATION - Abstract
Delves into the role of the church and non-government organizations (NGOs) in alleviating the impoverished state of people in India. Requirements that must be met by the NGOs to disseminate the knowledge of God's concerns for the country; Determinants of poverty in India, according to studies made in 1993 to 1994; Status of primary and adult education; Constructive responses to disasters; Promotion of medical care; Components of strategic interventions.
- Published
- 2003
- Full Text
- View/download PDF
47. Posthypnotic suggestions and behavior change: Highly hypnotizables compared with simulators.
- Author
-
GAUNITZ, SAMUEL C. B., NYSTRÖM-BONNIER, ELISABETH, and SKALIN, MARINA
- Published
- 1980
- Full Text
- View/download PDF
48. Transcendental meditation and heterohypnosis as altered states of consciousness.
- Author
-
Barmark, Susanne M. and Gaunitz, Samuel C. B.
- Abstract
The effects of transcendental meditation and relaxation-heterohypnosis on subjective phenomena and physiological arousal were examined. One group of Ss, who were experienced meditators, participated in meditation, and a second group of Ss, who were highly susceptible to hypnosis but with little hypnotic experience, were exposed to hypnosis. A period of quiet sitting served as control for Ss in each group. Neither heterohypnosis nor transcendental meditation were identified as low-arousal states. They were assumed to be similar phenomenologically altered states of consciousness, mainly characterized by changes in the distribution of attention and in body image. [ABSTRACT FROM PUBLISHER]
- Published
- 1979
- Full Text
- View/download PDF
49. A posthypnotically released emotion as a modifier of behavior.
- Author
-
Gaunitz, Samuel C. B., Unestml, Lars-Eric, and Berglund, Birgitta K.
- Abstract
The main purpose of the present experiment was to investigate whether a posthypnotically released emotion (i.e., a sense of happiness) could modify the frequency of a behavior performed by S. 7 highly susceptible Ss participated in the experiment. They received a posthypnotic suggestion with the implication that each time they made a certain response a sense of happiness would be released. They also received a suggestion of amnesia for the posthypnotic suggestion. In all 7 Ss the response evoked a sense of happiness. The frequency of the response increased significantly in all SS (p-01) [ABSTRACT FROM PUBLISHER]
- Published
- 1975
- Full Text
- View/download PDF
50. Posthypnotic suggestions and behavior change: Highly hypnotizables compared with simulators
- Author
-
Marina Skalin, Samuel C. B. Gaunitz, and Elisabeth Nyström‐Bonnier
- Subjects
medicine.medical_specialty ,media_common.quotation_subject ,Behavior change ,Amnesia ,General Medicine ,Stimulus (physiology) ,Audiology ,Developmental psychology ,Arts and Humanities (miscellaneous) ,Feeling ,Developmental and Educational Psychology ,medicine ,medicine.symptom ,Psychology ,General Psychology ,media_common - Abstract
The authenticity of a posthypnotically released emotion was examined to see whether this emotion also could modify the reaction times (RTs) of subjects. The simulant design proposed by Orne (1979) was utilized, with 10 highly hypnotizable subjects and 10 non-hypnotizable simulators participating in the experiment. The subjects received a post-hypnotic suggestion to the effect that every presentation of a light stimulus would release a feeling of discomfort and that a second light stimulus would be neutral. They were informed that they could terminate the stimulation by pressing a RT switch and received a suggestion of amnesia for the posthypnotic suggestion. The simulators skilfully imitated the objective behavior of the hypnotic subjects; their physiological reactions increased and their RTs were shorter when exposed to the aversive stimulation. The main differences occurred in the subjective reports. The hypnotic subjects reported that the emotion was released involuntarily and found relief in escaping from it, while the simulators reported no corresponding experiences, saying that they had deliberately manipulated the objective behavior.
- Published
- 1980
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