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1.
Comput Struct Biotechnol J ; 18: 913-921, 2020.
Article in English | MEDLINE | ID: mdl-32346464

ABSTRACT

While the majority of population-level genome sequencing initiatives claim to follow the principles of informed consent, the requirements for informed consent have not been-well defined in this context. In fact, the implementation of informed consent differs greatly across these initiatives - spanning broad consent, blanket consent, and tiered consent among others. As such, this calls for an investigation into the requirements for consent to be "informed" in the context of population genomics. One particular strategy that claims to be fully informed and to continuously engage participants is called "dynamic consent". Dynamic consent is based on a personalised communication platform that aims to facilitate the consent process. It is oriented to support continuous two-way communication between researchers and participants. In this paper, we analyze the requirements of informed consent in the context of population genomics, review various current implementations of dynamic consent, assess whether they fulfill the requirement of informed consent, and, in turn, enable participants to make autonomous and informed choices on whether or not to participate in research projects.

2.
Comput Struct Biotechnol J ; 17: 463-474, 2019.
Article in English | MEDLINE | ID: mdl-31007872

ABSTRACT

Informed consent is the result of tumultuous events in both the clinical and research arenas over the last 100 years. Throughout this time, the notion of informed consent has shifted tremendously, both due to advances in medicine, as well as the type of data being gathered. As such, informed consent has misaligned with the goals of medical research. It is becoming more and more vital to address this chasm, and begin building new frameworks to link this disconnect. Thus, we address three goals in this paper. First, we discuss the history of informed consent and unify the varying definitions of the term. Second, we evaluate the current research on the topic, classify them into themes, and attend to the problems therein. Lastly, we employ these themes of informed consent research mentioned previously to provide guidance and insight for future research in the arena.

3.
JMIR Med Inform ; 7(2): e12702, 2019 Apr 29.
Article in English | MEDLINE | ID: mdl-31033449

ABSTRACT

BACKGROUND: Biomedical research often requires large cohorts and necessitates the sharing of biomedical data with researchers around the world, which raises many privacy, ethical, and legal concerns. In the face of these concerns, privacy experts are trying to explore approaches to analyzing the distributed data while protecting its privacy. Many of these approaches are based on secure multiparty computations (SMCs). SMC is an attractive approach allowing multiple parties to collectively carry out calculations on their datasets without having to reveal their own raw data; however, it incurs heavy computation time and requires extensive communication between the involved parties. OBJECTIVE: This study aimed to develop usable and efficient SMC applications that meet the needs of the potential end-users and to raise general awareness about SMC as a tool that supports data sharing. METHODS: We have introduced distributed statistical computing (DSC) into the design of secure multiparty protocols, which allows us to conduct computations on each of the parties' sites independently and then combine these computations to form 1 estimator for the collective dataset, thus limiting communication to the final step and reducing complexity. The effectiveness of our privacy-preserving model is demonstrated through a linear regression application. RESULTS: Our secure linear regression algorithm was tested for accuracy and performance using real and synthetic datasets. The results showed no loss of accuracy (over nonsecure regression) and very good performance (20 min for 100 million records). CONCLUSIONS: We used DSC to securely calculate a linear regression model over multiple datasets. Our experiments showed very good performance (in terms of the number of records it can handle). We plan to extend our method to other estimators such as logistic regression.

4.
Hum Genomics ; 12(1): 19, 2018 04 10.
Article in English | MEDLINE | ID: mdl-29636096

ABSTRACT

Contemporary biomedical databases include a wide range of information types from various observational and instrumental sources. Among the most important features that unite biomedical databases across the field are high volume of information and high potential to cause damage through data corruption, loss of performance, and loss of patient privacy. Thus, issues of data governance and privacy protection are essential for the construction of data depositories for biomedical research and healthcare. In this paper, we discuss various challenges of data governance in the context of population genome projects. The various challenges along with best practices and current research efforts are discussed through the steps of data collection, storage, sharing, analysis, and knowledge dissemination.


Subject(s)
Biomedical Research/trends , Databases, Genetic , Genomics , Humans
5.
J Infect Dev Ctries ; 8(10): 1344-9, 2014 Oct 15.
Article in English | MEDLINE | ID: mdl-25313614

ABSTRACT

INTRODUCTION: The role of Origanum ehrenberjii against bacteria that cause enteric diseases is well known. Salmonella and Enterococcus cause high rates of enteric infections around the world. The aim of this study was to extract essential oils from cultivated and naturally growing O. ehrenberjii, compare the chemical profiles of the extracts and estimate their antimicrobial efficacy against enteric pathogens. METHODOLOGY: Sixteen compounds were recovered consistently from essential oils extracted from O. ehrenberjii of wild and cultivated origin. The chemical profiles were determined using GC-MS. Safety of the essential oils was determined by observing mortality of chicks after intramuscular administration of the oils. The antimicrobial efficacy of the oils against the enteric pathogens was determined by the Kirby-Bauer Single Disk Diffusion assay. RESULTS: The levels of thymol, carvacrol, para cymene and γ-terpinene were significantly different in the two oils. A significant difference in in vitro antimicrobial activity of the two oils against Salmonella enterica serovar Typhimurium was observed. Intramuscular administration of the two oils in one day-old chicks resulted in significant differences in mortality of 60% vs. 5% (p < 0.05) for wild and cultivated herbs respectively, reflecting the higher safety of the cultivated herb due to the differences in the levels of certain active ingredients. CONCLUSIONS: The chemical profile of essential oil of wild vs. cultivated O. ehrenberjii differ significantly at compound level, suggesting the reason for their significant difference in efficacy against Salmonella enterica serovar Typhimurium, and also significant differences in the toxicity of the two oils.


Subject(s)
Anti-Bacterial Agents/pharmacology , Enterococcus faecalis/drug effects , Oils, Volatile/pharmacology , Origanum/chemistry , Salmonella typhimurium/drug effects , Animals , Anti-Bacterial Agents/adverse effects , Anti-Bacterial Agents/analysis , Anti-Bacterial Agents/isolation & purification , Chickens , Gas Chromatography-Mass Spectrometry , Injections, Intramuscular , Microbial Sensitivity Tests , Oils, Volatile/adverse effects , Oils, Volatile/analysis , Oils, Volatile/isolation & purification , Survival Analysis
6.
Virol J ; 10: 243, 2013 Jul 25.
Article in English | MEDLINE | ID: mdl-23886034

ABSTRACT

BACKGROUND: The genetic basis for avian to mammalian host switching in influenza A virus is largely unknown. The human A/HK/156/1997 (H5N1) virus that transmitted from poultry possesses NS1 gene mutations F103L + M106I that are virulence determinants in the mouse model of pneumonia; however their individual roles have not been determined. The emergent A/Shanghai/patient1/2013(H7N9)-like viruses also possess these mutations which may contribute to their virulence and ability to switch species. METHODS: NS1 mutant viruses were constructed by reverse genetics and site directed mutagenesis on human and mouse-adapted backbones. Mouse infections assessed virulence, virus yield, tissue infection, and IFN induction. NS1 protein properties were assessed for subcellular distribution, IFN antagonism (mouse and human), CPSF30 and RIG-I domain binding, host transcription (microarray); and the natural prevalence of 103L and 106I mutants was assessed. RESULTS: Each of the F103L and M106I mutations contributes additively to virulence to reduce the lethal dose by >800 and >3,200 fold respectively by mediating alveolar tissue infection with >100 fold increased infectious yields. The 106I NS1 mutant lost CPSF binding but the 103L mutant maintained binding that correlated with an increased general decrease in host gene expression in human but not mouse cells. Each mutation positively modulated the inhibition of IFN induction in mouse cells and activation of the IFN-ß promoter in human cells but not in combination in human cells indicating negative epistasis. Each of the F103L and M106I mutations restored a defect in cytoplasmic localization of H5N1 NS1 in mouse cells. Human H1N1 and H3N2 NS1 proteins bound to the CARD, helicase and RD RIG-I domains, whereas the H5N1 NS1 with the same consensus 103F and 106M mutations did not bind these domains, which was totally or partially restored by the M106I or F103L mutations respectively. CONCLUSIONS: The F103L and M106I mutations in the H5N1 NS1 protein each increased IFN antagonism and mediated interstitial pneumonia in mice that was associated with increased cytoplasmic localization and altered host factor binding. These mutations may contribute to the ability of previous HPAI H5N1 and recent LPAI H7N9 and H6N1 (NS1-103L+106M) viruses to switch hosts and cause disease in humans.


Subject(s)
Cleavage And Polyadenylation Specificity Factor/metabolism , DEAD-box RNA Helicases/metabolism , Influenza A Virus, H5N1 Subtype/immunology , Influenza A Virus, H5N1 Subtype/pathogenicity , Interferons/antagonists & inhibitors , Mutation, Missense , Viral Nonstructural Proteins/metabolism , Amino Acid Substitution , Animals , DEAD Box Protein 58 , Female , Host-Pathogen Interactions , Humans , Influenza A Virus, H5N1 Subtype/isolation & purification , Lung/pathology , Lung/virology , Lung Diseases, Interstitial/pathology , Lung Diseases, Interstitial/virology , Mice , Mutagenesis, Site-Directed , Mutant Proteins/genetics , Mutant Proteins/metabolism , Reverse Genetics , Viral Nonstructural Proteins/genetics , Virulence , Virulence Factors/genetics , Virulence Factors/metabolism
7.
PLoS One ; 7(2): e31839, 2012.
Article in English | MEDLINE | ID: mdl-22363747

ABSTRACT

The role of the NS1 protein in modulating influenza A virulence and host range was assessed by adapting A/Hong Kong/1/1968 (H3N2) (HK-wt) to increased virulence in the mouse. Sequencing the NS genome segment of mouse-adapted variants revealed 11 mutations in the NS1 gene and 4 in the overlapping NEP gene. Using the HK-wt virus and reverse genetics to incorporate mutant NS gene segments, we demonstrated that all NS1 mutations were adaptive and enhanced virus replication (up to 100 fold) in mouse cells and/or lungs. All but one NS1 mutant was associated with increased virulence measured by survival and weight loss in the mouse. Ten of twelve NS1 mutants significantly enhanced IFN-ß antagonism to reduce the level of IFN ß production relative to HK-wt in infected mouse lungs at 1 day post infection, where 9 mutants induced viral yields in the lung that were equivalent to or significantly greater than HK-wt (up to 16 fold increase). Eight of 12 NS1 mutants had reduced or lost the ability to bind the 30 kDa cleavage and polyadenylation specificity factor (CPSF30) thus demonstrating a lack of correlation with reduced IFN ß production. Mutant NS1 genes resulted in increased viral mRNA transcription (10 of 12 mutants), and protein production (6 of 12 mutants) in mouse cells. Increased transcription activity was demonstrated in the influenza mini-genome assay for 7 of 11 NS1 mutants. Although we have shown gain-of-function properties for all mutant NS genes, the contribution of the NEP mutations to phenotypic changes remains to be assessed. This study demonstrates that NS1 is a multifunctional virulence factor subject to adaptive evolution.


Subject(s)
Adaptation, Biological/genetics , Host Specificity/genetics , Influenza A virus/genetics , Influenza, Human/virology , Mutation/genetics , Selection, Genetic , Viral Nonstructural Proteins/genetics , Adaptation, Biological/drug effects , Animals , Biological Assay , Gene Expression Regulation, Viral/drug effects , Half-Life , Host Specificity/drug effects , Humans , Influenza A virus/drug effects , Influenza A virus/growth & development , Influenza A virus/pathogenicity , Interferon-beta/biosynthesis , Interferon-beta/pharmacology , Lung/drug effects , Lung/pathology , Lung/virology , Mice , Molecular Sequence Data , Mutant Proteins/metabolism , Orthomyxoviridae Infections/pathology , Orthomyxoviridae Infections/virology , Protein Binding/drug effects , Protein Biosynthesis/drug effects , RNA, Messenger/genetics , RNA, Messenger/metabolism , Recombination, Genetic/genetics , Virulence/drug effects
8.
Emerg Microbes Infect ; 1(11): e42, 2012 Nov.
Article in English | MEDLINE | ID: mdl-26038410

ABSTRACT

Little is known about the processes that enable influenza A viruses to jump into new host species. Here we show that the non-structural protein1 nucleotide substitution, A374G, encoding the D125G(GAT→GGT) mutation, which evolved during the adaptation of a human virus within a mouse host, activates a novel donor splice site in the non-structural gene, hence producing a novel influenza A viral protein, NS3. Using synonymous 125G mutations that do not activate the novel donor splice site, NS3 was shown to provide replicative gain-of-function. The protein sequence of NS3 is similar to NS1 protein but with an internal deletion of a motif comprised of three antiparallel ß-strands spanning codons 126 to 168 in NS1. The NS1-125G(GGT) codon was also found in 33 natural influenza A viruses that were strongly associated with switching from avian to mammalian hosts, including human, swine and canine populations. In addition to the experimental human to mouse switch, the NS1-125G(GGT) codon was selected on avian to human transmission of the 1997 H5N1 and 1999 H9N2 lineages, as well as the avian to swine jump of 1979 H1N1 Eurasian swine influenza viruses, linking the NS1 125G(GGT) codon with host adaptation and switching among multiple species.

9.
Virol J ; 8: 13, 2011 Jan 12.
Article in English | MEDLINE | ID: mdl-21226922

ABSTRACT

BACKGROUND: To understand the evolutionary steps required for a virus to become virulent in a new host, a human influenza A virus (IAV), A/Hong Kong/1/68(H3N2) (HK-wt), was adapted to increased virulence in the mouse. Among eleven mutations selected in the NS1 gene, two mutations F103L and M106I had been previously detected in the highly virulent human H5N1 isolate, A/HK/156/97, suggesting a role for these mutations in virulence in mice and humans. RESULTS: To determine the selective advantage of these mutations, reverse genetics was used to rescue viruses containing each of the NS1 mouse adapted mutations into viruses possessing the HK-wt NS1 gene on the A/PR/8/34 genetic backbone. Both F103L and M106I NS1 mutations significantly enhanced growth in vitro (mouse and canine cells) and in vivo (BALB/c mouse lungs) as well as enhanced virulence in the mouse. Only the M106I NS1 mutation enhanced growth in human cells. Furthermore, these NS1 mutations enhanced early viral protein synthesis in MDCK cells and showed an increased ability to replicate in mouse interferon ß (IFN-ß) pre-treated mouse cells relative to rPR8-HK-NS-wt NS1. The double mutant, rPR8-HK-NS-F103L + M106I, demonstrated growth attenuation late in infection due to increased IFN-ß induction in mouse cells. We then generated a rPR8 virus possessing the A/HK/156/97 NS gene that possesses 103L + 106I, and then rescued the L103F + I106M mutant. The 103L + 106I mutations increased virulence by >10 fold in BALB/c mice. We also inserted the avian A/Ck/Beijing/1/95 NS1 gene (the source lineage of the A/HK/156/97 NS1 gene) that possesses 103L + 106I, onto the A/WSN/33 backbone and then generated the L103F + I106M mutant. None of the H5N1 and H9N2 NS containing viruses resulted in increased IFN-ß induction. The rWSN-A/Ck/Beijing/1/95-NS1 gene possessing 103L and 106I demonstrated 100 fold enhanced growth and >10 fold enhanced virulence that was associated with increased tropism for lung alveolar and bronchiolar tissues relative to the corresponding L103F and I106M mutant. CONCLUSIONS: The F103L and M106I NS1 mutations were adaptive genetic determinants of growth and virulence in both human and avian NS1 genes in the mouse model.


Subject(s)
Influenza A Virus, H3N2 Subtype/pathogenicity , Mutation, Missense , Viral Nonstructural Proteins/metabolism , Virulence Factors/metabolism , Virus Replication , Adaptation, Biological , Animals , Disease Models, Animal , Female , Humans , Influenza A Virus, H3N2 Subtype/genetics , Influenza A Virus, H3N2 Subtype/isolation & purification , Influenza, Human/virology , Mice , Mice, Inbred BALB C , Mutant Proteins/genetics , Mutant Proteins/metabolism , Orthomyxoviridae Infections/pathology , Orthomyxoviridae Infections/virology , Survival Analysis , Viral Load , Viral Nonstructural Proteins/genetics , Viral Plaque Assay , Virulence , Virulence Factors/genetics
10.
J Virol ; 84(20): 10606-18, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20702632

ABSTRACT

Serial mouse lung passage of a human influenza A virus, A/Hong Kong/1/68 (H3N2) (HK-wt), produced a mouse-adapted variant, MA, with nine mutations that was >10(3.8)-fold more virulent. In this study, we demonstrate that MA mutations of the PB2 (D701N) and hemagglutinin (HA) (G218W in HA1 and T156N in HA2) genes were the most adaptive genetic determinants for increased growth and virulence in the mouse model. Recombinant viruses expressing each of the mutated MA genome segments on the HK-wt backbone showed significantly increased disease severity, whereas only the mouse-adapted PB2 gene increased virulence, as determined by the 50% lethal dose ([LD(50)] >10(1.4)-fold). The converse comparisons of recombinant MA viruses expressing each of the HK-wt genome segments showed the greatest decrease in virulence due to the HA gene (10(2)-fold), with lesser decreases due to the M1, NS1, NA, and PB1 genes (10(0.3)- to 10(0.8)-fold), and undetectable effects on the LD(50) for the PB2 and NP genes. The HK PB2 gene did, however, attenuate MA infection, as measured by weight loss and time to death. Replication of adaptive mutations in vivo and in vitro showed both viral gene backbone and host range effects. Minigenome transcription assays showed that PB1 and PB2 mutations increased polymerase activity and that the PB2 D701N mutation was comparable in effect to the mammalian adaptive PB2 E627K mutation. Our results demonstrate that host range and virulence are controlled by multiple genes, with major roles for mutations in PB2 and HA.


Subject(s)
Hemagglutinin Glycoproteins, Influenza Virus/genetics , Influenza A Virus, H3N2 Subtype/genetics , Influenza A Virus, H3N2 Subtype/pathogenicity , Mutation, Missense , RNA-Dependent RNA Polymerase/genetics , Viral Proteins/genetics , Adaptation, Physiological , Amino Acid Substitution , Animals , Cell Line , Female , Genes, Viral , Hemagglutinin Glycoproteins, Influenza Virus/physiology , Host-Pathogen Interactions/genetics , Host-Pathogen Interactions/physiology , Humans , Influenza A Virus, H3N2 Subtype/physiology , Mice , Molecular Sequence Data , RNA-Dependent RNA Polymerase/physiology , Viral Proteins/physiology , Virulence/genetics , Virulence/physiology , Virus Replication/genetics , Virus Replication/physiology
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