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1.
Cell ; 180(5): 878-894.e19, 2020 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-32059783

RESUMO

Pathogenic autoantibodies arise in many autoimmune diseases, but it is not understood how the cells making them evade immune checkpoints. Here, single-cell multi-omics analysis demonstrates a shared mechanism with lymphoid malignancy in the formation of public rheumatoid factor autoantibodies responsible for mixed cryoglobulinemic vasculitis. By combining single-cell DNA and RNA sequencing with serum antibody peptide sequencing and antibody synthesis, rare circulating B lymphocytes making pathogenic autoantibodies were found to comprise clonal trees accumulating mutations. Lymphoma driver mutations in genes regulating B cell proliferation and V(D)J mutation (CARD11, TNFAIP3, CCND3, ID3, BTG2, and KLHL6) were present in rogue B cells producing the pathogenic autoantibody. Antibody V(D)J mutations conferred pathogenicity by causing the antigen-bound autoantibodies to undergo phase transition to insoluble aggregates at lower temperatures. These results reveal a pre-neoplastic stage in human lymphomagenesis and a cascade of somatic mutations leading to an iconic pathogenic autoantibody.


Assuntos
Autoanticorpos/genética , Doenças Autoimunes/genética , Linfócitos B/imunologia , Linfoma/genética , Animais , Autoanticorpos/imunologia , Doenças Autoimunes/imunologia , Doenças Autoimunes/patologia , Linfócitos B/patologia , Proteínas Adaptadoras de Sinalização CARD/genética , Proteínas de Transporte/genética , Evolução Clonal/genética , Evolução Clonal/imunologia , Ciclina D3/genética , Guanilato Ciclase/genética , Humanos , Proteínas Imediatamente Precoces/genética , Região Variável de Imunoglobulina/genética , Região Variável de Imunoglobulina/imunologia , Proteínas Inibidoras de Diferenciação/genética , Linfoma/imunologia , Linfoma/patologia , Camundongos , Mutação/genética , Mutação/imunologia , Proteínas de Neoplasias/genética , Análise de Sequência de DNA/métodos , Análise de Sequência de RNA/métodos , Análise de Célula Única/métodos , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/genética , Proteínas Supressoras de Tumor/genética , Recombinação V(D)J/genética
2.
Nature ; 605(7909): 349-356, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35477763

RESUMO

Although circumstantial evidence supports enhanced Toll-like receptor 7 (TLR7) signalling as a mechanism of human systemic autoimmune disease1-7, evidence of lupus-causing TLR7 gene variants is lacking. Here we describe human systemic lupus erythematosus caused by a TLR7 gain-of-function variant. TLR7 is a sensor of viral RNA8,9 and binds to guanosine10-12. We identified a de novo, previously undescribed missense TLR7Y264H variant in a child with severe lupus and additional variants in other patients with lupus. The TLR7Y264H variant selectively increased sensing of guanosine and 2',3'-cGMP10-12, and was sufficient to cause lupus when introduced into mice. We show that enhanced TLR7 signalling drives aberrant survival of B cell receptor (BCR)-activated B cells, and in a cell-intrinsic manner, accumulation of CD11c+ age-associated B cells and germinal centre B cells. Follicular and extrafollicular helper T cells were also increased but these phenotypes were cell-extrinsic. Deficiency of MyD88 (an adaptor protein downstream of TLR7) rescued autoimmunity, aberrant B cell survival, and all cellular and serological phenotypes. Despite prominent spontaneous germinal-centre formation in Tlr7Y264H mice, autoimmunity was not ameliorated by germinal-centre deficiency, suggesting an extrafollicular origin of pathogenic B cells. We establish the importance of TLR7 and guanosine-containing self-ligands for human lupus pathogenesis, which paves the way for therapeutic TLR7 or MyD88 inhibition.


Assuntos
Mutação com Ganho de Função , Lúpus Eritematoso Sistêmico , Receptor 7 Toll-Like , Animais , Autoimunidade/genética , Linfócitos B , GMP Cíclico/análogos & derivados , Guanosina , Humanos , Lúpus Eritematoso Sistêmico/genética , Camundongos , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Receptor 7 Toll-Like/genética , Receptor 7 Toll-Like/metabolismo
3.
Proc Natl Acad Sci U S A ; 119(36): e2202795119, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-36037362

RESUMO

Parasitic helminth infections, while a major cause of neglected tropical disease burden, negatively correlate with the incidence of immune-mediated inflammatory diseases such as inflammatory bowel diseases (IBD). To evade expulsion, helminths have developed sophisticated mechanisms to regulate their host's immune responses. Controlled experimental human helminth infections have been assessed clinically for treating inflammatory conditions; however, such a radical therapeutic modality has challenges. An alternative approach is to harness the immunomodulatory properties within the worm's excretory-secretory (ES) complement, its secretome. Here, we report a biologics discovery and validation pipeline to generate and screen in vivo a recombinant cell-free secretome library of helminth-derived immunomodulatory proteins. We successfully expressed 78 recombinant ES proteins from gastrointestinal hookworms and screened the crude in vitro translation reactions for anti-IBD properties in a mouse model of acute colitis. After statistical filtering and ranking, 20 proteins conferred significant protection against various parameters of colitis. Lead candidates from distinct protein families, including annexins, transthyretins, nematode-specific retinol-binding proteins, and SCP/TAPS were identified. Representative proteins were produced in mammalian cells and further validated, including ex vivo suppression of inflammatory cytokine secretion by T cells from IBD patient colon biopsies. Proteins identified herein offer promise as novel, safe, and mechanistically differentiated biologics for treating the globally increasing burden of inflammatory diseases.


Assuntos
Anti-Inflamatórios , Produtos Biológicos , Colite , Proteínas de Helminto , Doenças Inflamatórias Intestinais , Animais , Anti-Inflamatórios/farmacologia , Produtos Biológicos/farmacologia , Colite/tratamento farmacológico , Proteínas de Helminto/genética , Proteínas de Helminto/farmacologia , Helmintos , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/parasitologia , Camundongos
4.
Hum Genomics ; 17(1): 106, 2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-38007520

RESUMO

BACKGROUND: Past studies suggest that there are changes in peripheral blood cell gene expression in response to ischaemic stroke; however, the specific changes which occur during the acute phase are poorly characterised. The current study aimed to identify peripheral blood cell genes specifically associated with the early response to ischaemic stroke using whole blood samples collected from participants diagnosed with ischaemic stroke (n = 29) or stroke mimics (n = 27) following emergency presentation to hospital. Long non-coding RNA (lncRNA), mRNA and micro-RNA (miRNA) abundance was measured by RNA-seq, and the consensusDE package was used to identify genes which were differentially expressed between groups. A sensitivity analysis excluding two participants with metastatic disease was also conducted. RESULTS: The mean time from symptom onset to blood collection was 2.6 h. Most strokes were mild (median NIH stroke scale score 2.0). Ten mRNAs (all down-regulated in samples provided by patients experiencing ischaemic stroke) and 30 miRNAs (14 over-expressed and 16 under-expressed in participants with ischaemic stroke) were significantly different between groups in the whole cohort and sensitivity analyses. No significant over-representation of gene ontology categories by the differentially expressed genes was observed. Random forest analysis suggested a panel of differentially expressed genes (ADGRG7 and miRNAs 96, 532, 6766, 6798 and 6804) as potential ischaemic stroke biomarkers, although modelling analyses demonstrated that these genes had poor diagnostic performance. CONCLUSIONS: This study provides evidence suggesting that the early response to minor ischaemic stroke is predominantly reflected by changes in the expression of miRNAs in peripheral blood cells. Further work in independent cohorts particularly in patients with more severe stroke is needed to validate these findings and investigate their clinical relevance.


Assuntos
Isquemia Encefálica , AVC Isquêmico , MicroRNAs , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/genética , Isquemia Encefálica/genética , Isquemia Encefálica/complicações , AVC Isquêmico/diagnóstico , AVC Isquêmico/genética , AVC Isquêmico/complicações , MicroRNAs/genética , Estudos de Casos e Controles , Expressão Gênica
5.
Bioinformatics ; 38(17): 4220-4222, 2022 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-35801945

RESUMO

SUMMARY: Missense mutations that change protein stability are strongly associated with human genetic disease. With the recent availability of predicted structures for all human proteins generated using the AlphaFold2 prediction model, genome-wide assessment of the stability effects of genetic variation can, for the first time, be easily performed. This facilitates the interrogation of personal genetic variation for potentially pathogenic effects through the application of stability metrics. Here, we present a novel tool to prioritize variants predicted to cause strong instability in essential proteins. We show that by filtering by ΔΔG values and then prioritizing by StabilitySort Z-scores, we are able to more accurately discriminate pathogenic, protein-destabilizing mutations from population variation, compared with other mutation effect predictors. AVAILABILITY AND IMPLEMENTATION: StabilitySort is available as a web service (https://www.stabilitysort.org), as a data download for integration with other tools (https://www.stabilitysort.org/download) or can be deployed as a standalone system from source code (https://gitlab.com/baaron/StabilitySort). SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Genoma , Software , Humanos , Proteínas/genética , Estabilidade Proteica , Mutação , Variação Genética
6.
Nicotine Tob Res ; 25(7): 1269-1276, 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-36929415

RESUMO

INTRODUCTION: A considerable number of people successfully give up tobacco smoking. In nicotine-dependent individuals, tobacco choice is determined by greater expected drug value; however, less is known about the underlying mechanisms through which people quit smoking. AIMS AND METHODS: This study aimed to explore whether computational parameters of value-based decision-making (VBDM) characterize recovery from nicotine addiction. Using a preregistered, between-subject design, current daily smokers (n = 51) and ex-smokers who used to smoke daily (n = 51) were recruited from the local community. Participants completed a two-alternative forced choice task in which they chose between either two tobacco-related images (in one block) or tobacco-unrelated images (in a different block). During each trial, participants pressed a computer key to select the image they rated most positively during a previous task block. To estimate evidence accumulation (EA) processes and response thresholds during the different blocks, a drift-diffusion model was fitted to the reaction time and error data. RESULTS: Ex-smokers had significantly higher response thresholds when making tobacco-related decisions (p = .01, d = 0.45) compared to current smokers, although there were no significant group differences during tobacco-unrelated decisions. Furthermore, there were no significant group differences in EA rates when making tobacco or tobacco-unrelated decisions. CONCLUSIONS: Greater cautiousness when making value-based decisions about tobacco-related cues characterized recovery from nicotine addiction. IMPLICATIONS: The number of people dependent on nicotine has decreased steadily during the past decade; however, the mechanisms that underlie recovery are currently less well understood. The present study applied advances in the measurement of value-based choice. The aim was to explore whether the internal processes that underpin VBDM discriminate current daily tobacco smokers from ex-tobacco smokers who used to smoke daily. Findings revealed that recovery from nicotine addiction was characterized by higher response thresholds when making value-based decisions about tobacco-related cues; this may serve as a novel target for treatment interventions that focus on helping people to stop smoking.


Assuntos
Abandono do Hábito de Fumar , Tabagismo , Humanos , Tabagismo/terapia , Nicotina , Fumantes , Ex-Fumantes , Abandono do Hábito de Fumar/métodos
7.
Proc Natl Acad Sci U S A ; 117(34): 20848-20859, 2020 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-32778586

RESUMO

Tuberculosis (TB) claims 1.5 million lives per year. This situation is largely due to the low efficacy of the only licensed TB vaccine, Bacillus Calmette-Guérin (BCG) against pulmonary TB. The metabolic disease type 2 diabetes (T2D) is a risk factor for TB and the mechanisms underlying increased TB susceptibility in T2D are not well understood. Furthermore, it is unknown if new TB vaccines will provide protection in the context of T2D. Here we used a diet-induced murine model of T2D to investigate the underlying mechanisms of TB/T2D comorbidity and to evaluate the protective capacity of two experimental TB vaccines in comparison to conventional BCG. Our data reveal a distinct immune dysfunction that is associated with diminished recognition of mycobacterial antigens in T2D. More importantly, we provide compelling evidence that mucosal delivery of recombinant BCG strains expressing the Mycobacterium tuberculosis (Mtb) ESX-1 secretion system (BCG::RD1 and BCG::RD1 ESAT-6 ∆92-95) are safe and confer superior immunity against aerosol Mtb infection in the context of T2D. Our findings suggest that the remarkable anti-TB immunity by these recombinant BCG strains is achieved via augmenting the numbers and functional capacity of antigen presenting cells in the lungs of diabetic mice.


Assuntos
Antígenos de Bactérias/farmacologia , Proteínas de Bactérias/farmacologia , Diabetes Mellitus Tipo 2/metabolismo , Animais , Antígenos de Bactérias/imunologia , Antígenos de Bactérias/metabolismo , Vacina BCG , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/metabolismo , Diabetes Mellitus Experimental , Modelos Animais de Doenças , Pulmão/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mucosa/imunologia , Mycobacterium bovis/imunologia , Mycobacterium tuberculosis/imunologia , Tuberculose/imunologia , Vacinas contra a Tuberculose/imunologia , Vacinação
8.
J Med Internet Res ; 25: e46523, 2023 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-37707943

RESUMO

BACKGROUND: Evaluating digital interventions using remote methods enables the recruitment of large numbers of participants relatively conveniently and cheaply compared with in-person methods. However, conducting research remotely based on participant self-report with little verification is open to automated "bots" and participant deception. OBJECTIVE: This paper uses a case study of a remotely conducted trial of an alcohol reduction app to highlight and discuss (1) the issues with participant deception affecting remote research trials with financial compensation; and (2) the importance of rigorous data management to detect and address these issues. METHODS: We recruited participants on the internet from July 2020 to March 2022 for a randomized controlled trial (n=5602) evaluating the effectiveness of an alcohol reduction app, Drink Less. Follow-up occurred at 3 time points, with financial compensation offered (up to £36 [US $39.23]). Address authentication and telephone verification were used to detect 2 kinds of deception: "bots," that is, automated responses generated in clusters; and manual participant deception, that is, participants providing false information. RESULTS: Of the 1142 participants who enrolled in the first 2 months of recruitment, 75.6% (n=863) of them were identified as bots during data screening. As a result, a CAPTCHA (Completely Automated Public Turing Test to Tell Computers and Humans Apart) was added, and after this, no more bots were identified. Manual participant deception occurred throughout the study. Of the 5956 participants (excluding bots) who enrolled in the study, 298 (5%) were identified as false participants. The extent of this decreased from 110 in November 2020, to a negligible level by February 2022 including a number of months with 0. The decline occurred after we added further screening questions such as attention checks, removed the prominence of financial compensation from social media advertising, and added an additional requirement to provide a mobile phone number for identity verification. CONCLUSIONS: Data management protocols are necessary to detect automated bots and manual participant deception in remotely conducted trials. Bots and manual deception can be minimized by adding a CAPTCHA, attention checks, a requirement to provide a phone number for identity verification, and not prominently advertising financial compensation on social media. TRIAL REGISTRATION: ISRCTN Number ISRCTN64052601; https://doi.org/10.1186/ISRCTN64052601.


Assuntos
Telefone Celular , Software , Humanos , Publicidade , Gerenciamento de Dados , Etanol , Enganação
9.
Clin Microbiol Rev ; 34(4): e0034820, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34494873

RESUMO

About half of the world's population and 80% of the world's biodiversity can be found in the tropics. Many diseases are specific to the tropics, with at least 41 diseases caused by endemic bacteria, viruses, parasites, and fungi. Such diseases are of increasing concern, as the geographic range of tropical diseases is expanding due to climate change, urbanization, change in agricultural practices, deforestation, and loss of biodiversity. While traditional medicines have been used for centuries in the treatment of tropical diseases, the active natural compounds within these medicines remain largely unknown. In this review, we describe infectious diseases specific to the tropics, including their causative pathogens, modes of transmission, recent major outbreaks, and geographic locations. We further review current treatments for these tropical diseases, carefully consider the biodiscovery potential of the tropical biome, and discuss a range of technologies being used for drug development from natural resources. We provide a list of natural products with antimicrobial activity, detailing the source organisms and their effectiveness as treatment. We discuss how technological advancements, such as next-generation sequencing, are driving high-throughput natural product screening pipelines to identify compounds with therapeutic properties. This review demonstrates the impact natural products from the vast tropical biome have in the treatment of tropical infectious diseases and how high-throughput technical capacity will accelerate this discovery process.


Assuntos
Produtos Biológicos , Doenças Transmissíveis , Biodiversidade , Produtos Biológicos/uso terapêutico , Doenças Transmissíveis/tratamento farmacológico , Doenças Transmissíveis/epidemiologia , Humanos , Clima Tropical
10.
BMC Genomics ; 22(1): 188, 2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33726677

RESUMO

BACKGROUND: Basenjis are considered an ancient dog breed of central African origins that still live and hunt with tribesmen in the African Congo. Nicknamed the barkless dog, Basenjis possess unique phylogeny, geographical origins and traits, making their genome structure of great interest. The increasing number of available canid reference genomes allows us to examine the impact the choice of reference genome makes with regard to reference genome quality and breed relatedness. RESULTS: Here, we report two high quality de novo Basenji genome assemblies: a female, China (CanFam_Bas), and a male, Wags. We conduct pairwise comparisons and report structural variations between assembled genomes of three dog breeds: Basenji (CanFam_Bas), Boxer (CanFam3.1) and German Shepherd Dog (GSD) (CanFam_GSD). CanFam_Bas is superior to CanFam3.1 in terms of genome contiguity and comparable overall to the high quality CanFam_GSD assembly. By aligning short read data from 58 representative dog breeds to three reference genomes, we demonstrate how the choice of reference genome significantly impacts both read mapping and variant detection. CONCLUSIONS: The growing number of high-quality canid reference genomes means the choice of reference genome is an increasingly critical decision in subsequent canid variant analyses. The basal position of the Basenji makes it suitable for variant analysis for targeted applications of specific dog breeds. However, we believe more comprehensive analyses across the entire family of canids is more suited to a pangenome approach. Collectively this work highlights the importance the choice of reference genome makes in all variation studies.


Assuntos
Lobos , Animais , China , Cromossomos , Cães , Feminino , Genoma , Genômica , Masculino , Lobos/genética
11.
Int J Cancer ; 149(5): 1089-1099, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-33821477

RESUMO

Prostate cancer (PrCa) is highly heritable, and although rare variants contribute significantly to PrCa risk, few have been identified to date. Herein, whole-genome sequencing was performed in a large PrCa family featuring multiple affected relatives spanning several generations. A rare, predicted splice site EZH2 variant, rs78589034 (G > A), was identified as segregating with disease in all but two individuals in the family, one of whom was affected with lymphoma and bowel cancer and a female relative. This variant was significantly associated with disease risk in combined familial and sporadic PrCa datasets (n = 1551; odds ratio [OR] = 3.55, P = 1.20 × 10-5 ). Transcriptome analysis was performed on prostate tumour needle biopsies available for two rare variant carriers and two wild-type cases. Although no allele-dependent differences were detected in EZH2 transcripts, a distinct differential gene expression signature was observed when comparing prostate tissue from the rare variant carriers with the wild-type samples. The gene expression signature comprised known downstream targets of EZH2 and included the top-ranked genes, DUSP1, FOS, JUNB and EGR1, which were subsequently validated by qPCR. These data provide evidence that rs78589034 is associated with increased PrCa risk in Tasmanian men and further, that this variant may be associated with perturbed EZH2 function in prostate tissue. Disrupted EZH2 function is a driver of tumourigenesis in several cancers, including prostate, and is of significant interest as a therapeutic target.


Assuntos
Biomarcadores Tumorais/genética , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Neoplasias da Próstata/epidemiologia , Transcriptoma , Idoso , Idoso de 80 Anos ou mais , Seguimentos , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Fatores de Risco , Tasmânia/epidemiologia , Células Tumorais Cultivadas , Estados Unidos/epidemiologia
12.
Immunol Cell Biol ; 99(2): 146-156, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32623783

RESUMO

Sequencing the first human genome in 2003 took 15 years and cost $2.7 billion. Advances in sequencing technologies have since decreased costs to the point where it is now feasible to resequence a whole human genome for $1000 in a single day. These advances have allowed the generation of huge volumes of high-quality human sequence data used to construct increasingly large catalogs of both population-level and disease-causing variation. The existence of such databases, coupled with a high-quality human reference genome, means we are able to interrogate and annotate all types of genetic variation and identify pathogenic variants for many diseases. Increasingly, sequencing-based approaches are being used to elucidate the underlying genetic cause of autoimmune diseases, a group of roughly 80 polygenic diseases characterized by abnormal immune responses where healthy tissue is attacked. Although sequence data generation has become routine and affordable, significant challenges remain with no gold-standard methodology to identify pathogenic variants currently available. This review examines the latest methodologies used to identify pathogenic variants in autoimmune diseases and considers available sequencing options and subsequent bioinformatic methodologies and strategies. The development of reliable and robust sequencing and analytic workflows to detect pathogenic variants is critical to realize the potential of precision medicine programs where patient variant information is used to inform clinical practice.


Assuntos
Doenças Autoimunes , Sequenciamento de Nucleotídeos em Larga Escala , Doenças Autoimunes/genética , Biologia Computacional , Análise Mutacional de DNA , Variação Genética/genética , Humanos
13.
Mol Ecol ; 30(5): 1174-1189, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33421231

RESUMO

Population genomic approaches can characterize dispersal across a single generation through to many generations in the past, bridging the gap between individual movement and intergenerational gene flow. These approaches are particularly useful when investigating dispersal in recently altered systems, where they provide a way of inferring long-distance dispersal between newly established populations and their interactions with existing populations. Human-mediated biological invasions represent such altered systems which can be investigated with appropriate study designs and analyses. Here we apply temporally restricted sampling and a range of population genomic approaches to investigate dispersal in a 2004 invasion of Aedes albopictus (the Asian tiger mosquito) in the Torres Strait Islands (TSI) of Australia. We sampled mosquitoes from 13 TSI villages simultaneously and genotyped 373 mosquitoes at genome-wide single nucleotide polymorphisms (SNPs): 331 from the TSI, 36 from Papua New Guinea (PNG) and four incursive mosquitoes detected in uninvaded regions. Within villages, spatial genetic structure varied substantially but overall displayed isolation by distance and a neighbourhood size of 232-577. Close kin dyads revealed recent movement between islands 31-203 km apart, and deep learning inferences showed incursive Ae. albopictus had travelled to uninvaded regions from both adjacent and nonadjacent islands. Private alleles and a co-ancestry matrix indicated direct gene flow from PNG into nearby islands. Outlier analyses also detected four linked alleles introgressed from PNG, with the alleles surrounding 12 resistance-associated cytochrome P450 genes. By treating dispersal as both an intergenerational process and a set of discrete events, we describe a highly interconnected invasive system.


Assuntos
Aedes , Mosquitos Vetores , Animais , Austrália , Humanos , Ilhas , Metagenômica , Papua Nova Guiné
14.
Europace ; 23(3): 441-450, 2021 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-33200177

RESUMO

AIMS: In 2003, an Australian woman was convicted by a jury of smothering and killing her four children over a 10-year period. Each child died suddenly and unexpectedly during a sleep period, at ages ranging from 19 days to 18 months. In 2019 we were asked to investigate if a genetic cause could explain the children's deaths as part of an inquiry into the mother's convictions. METHODS AND RESULTS: Whole genomes or exomes of the mother and her four children were sequenced. Functional analysis of a novel CALM2 variant was performed by measuring Ca2+-binding affinity, interaction with calcium channels and channel function. We found two children had a novel calmodulin variant (CALM2 G114R) that was inherited maternally. Three genes (CALM1-3) encode identical calmodulin proteins. A variant in the corresponding residue of CALM3 (G114W) was recently reported in a child who died suddenly at age 4 and a sibling who suffered a cardiac arrest at age 5. We show that CALM2 G114R impairs calmodulin's ability to bind calcium and regulate two pivotal calcium channels (CaV1.2 and RyR2) involved in cardiac excitation contraction coupling. The deleterious effects of G114R are similar to those produced by G114W and N98S, which are considered arrhythmogenic and cause sudden cardiac death in children. CONCLUSION: A novel functional calmodulin variant (G114R) predicted to cause idiopathic ventricular fibrillation, catecholaminergic polymorphic ventricular tachycardia, or mild long QT syndrome was present in two children. A fatal arrhythmic event may have been triggered by their intercurrent infections. Thus, calmodulinopathy emerges as a reasonable explanation for a natural cause of their deaths.


Assuntos
Infanticídio , Taquicardia Ventricular , Arritmias Cardíacas , Austrália , Criança , Pré-Escolar , Morte Súbita Cardíaca/etiologia , Feminino , Humanos , Lactente , Canal de Liberação de Cálcio do Receptor de Rianodina , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/genética
15.
Appetite ; 157: 104986, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33039507

RESUMO

Theoretical models suggest that food-related visual attentional bias (AB) may be related to appetitive motivational states and individual differences in body weight; however, findings in this area are equivocal. We conducted a systematic review and series of meta-analyses to determine if there is a positive association between food-related AB and: (1.) body mass index (BMI) (number of effect sizes (k) = 110), (2.) hunger (k = 98), (3.) subjective craving for food (k = 35), and (4.) food intake (k = 44). Food-related AB was robustly associated with craving (r = 0.134 (95% CI 0.061, 0.208); p < .001), food intake (r = 0.085 (95% CI 0.038, 0.132); p < .001), and hunger (r = 0.048 (95% CI 0.016, 0.079); p = .003), but these correlations were small. Food-related AB was unrelated to BMI (r = 0.008 (95% CI -0.020, 0.035); p = .583) and this result was not moderated by type of food stimuli, method of AB assessment, or the subcomponent of AB that was examined. Furthermore, in a between-groups analysis (k = 22) which directly compared participants with overweight/obesity to healthy-weight control groups, there was no evidence for an effect of weight status on food-related AB (Hedge's g = 0.104, (95% CI -0.050, 0.258); p = .186). Taken together, these findings suggest that food-related AB is sensitive to changes in the motivational value of food, but is unrelated to individual differences in body weight. Our findings question the traditional view of AB as a trait-like index of preoccupation with food and have implications for novel theoretical perspectives on the role of food AB in appetite control and obesity.


Assuntos
Viés de Atenção , Peso Corporal , Sinais (Psicologia) , Humanos , Fome , Motivação
16.
Int J Mol Sci ; 22(4)2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33562731

RESUMO

The distinct properties of allo-reactive T-cell repertoires are not well understood. To investigate whether auto-reactive and allo-reactive T-cell repertoires encoded distinct properties, we used dextramer enumeration, enrichment, single-cell T-cell receptor (TCR) sequencing and multiparameter analysis. We found auto-reactive and allo-reactive T-cells differed in mean ex vivo frequency which was antigen dependent. Allo-reactive T-cells showed clear differences in TCR architecture, with enriched usage of specific T-cell receptor variable (TRBJ) genes and broader use of T-cell receptor variable joining (TRBJ) genes. Auto-reactive T-cell repertoires exhibited complementary determining regions three (CDR3) lengths using a Gaussian distribution whereas allo-reactive T-cell repertoires exhibited distorted patterns in CDR3 length. CDR3 loops from allo-reactive T-cells showed distinct physical-chemical properties, tending to encode loops that were more acidic in charge. Allo-reactive T-cell repertoires differed in diversity metrics, tending to show increased overall diversity and increased homogeneity between repertoires. Motif analysis of CDR3 loops showed allo-reactive T-cell repertoires differed in motif preference which included broader motif use. Collectively, these data conclude that allo-reactive T-cell repertoires are indeed different to auto-reactive repertoires and provide tangible metrics for further investigations and validation. Given that the antigens studied here are overexpressed on multiple cancers and that allo-reactive TCRs often show increased ligand affinity, this new TCR bank also has translational potential for adoptive cell therapy, soluble TCR-based therapy and rational TCR design.


Assuntos
Antígenos de Neoplasias/genética , Receptores de Antígenos de Linfócitos T/genética , Linfócitos T/citologia , Perfilação da Expressão Gênica , Humanos , Análise de Sequência de RNA , Análise de Célula Única/métodos , Linfócitos T/química
17.
Subst Use Misuse ; 55(1): 167-173, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31455135

RESUMO

Background: Impaired inhibitory control is thought to contribute to alcohol (mis)use. However, current definitions of inhibitory control are over-simplified by a failure to distinguish reactive inhibitory control from proactive slowing. Objectives: To distinguish "reactive" inhibitory control and proactive slowing in heavy drinkers, and characterize associations between both constructs and individual differences in alcohol consumption. Methods: Sixty heavy drinkers completed self-reported measures of alcohol consumption, followed by two modified Stop-Signal tasks and an AX-continuous performance task in a laboratory setting. Results: Heavy drinkers demonstrated proactive slowing when inhibition was more likely but individual differences in proactive slowing and reactive stopping were unrelated to individual differences in alcohol consumption. Conclusions/Importance: Within a sample of heavy drinkers, individual differences in reactive inhibitory control and proactive slowing are unrelated to individual differences in alcohol consumption.


Assuntos
Consumo de Bebidas Alcoólicas/psicologia , Função Executiva/fisiologia , Inibição Psicológica , Adolescente , Adulto , Feminino , Humanos , Individualidade , Masculino , Testes Neuropsicológicos , Adulto Jovem
18.
Appetite ; 133: 93-100, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30300670

RESUMO

Attentional biases for reward-related (e.g., food, alcohol) cues are moderated by the expectation of imminent reward availability, but the psychological mechanisms that underlie this effect are unclear. We report two studies in which we investigated if effects of reward gain anticipation are specific to the type of reward that is anticipated, and if anticipation of loss has comparable effects to anticipation of reward gain. We used an eye tracking task to investigate the effects of anticipation of gain (experiment 1) or loss (experiment 2) of alcohol and chocolate on attentional bias for alcohol and chocolate pictures using full crossover designs; the effects of uncertain outcomes were investigated in both experiments. Results indicated robust effects of anticipation of reward gain and uncertainty on attentional bias that were outcome-specific (experiment 1). However attentional bias was not influenced by loss anticipation (experiment 2). Our findings demonstrate that anticipation of reward gain increases attentional bias for the type of reward that is anticipated, but anticipation of loss does not influence attentional bias.


Assuntos
Viés de Atenção , Sinais (Psicologia) , Recompensa , Adolescente , Bebidas Alcoólicas , Chocolate , Estudos Cross-Over , Feminino , Fixação Ocular , Humanos , Masculino , Adulto Jovem
19.
Subst Use Misuse ; 54(4): 692-698, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30572780

RESUMO

BACKGROUND: Attentional bias (AB) is the tendency for substance-related stimuli to grab attention. The addiction Stroop task is widely used for measuring AB in the lab, but it has poor reliability and inconsistent predictive validity. Therefore, there is a need to improve the psychometric properties of the task. OBJECTIVES: This study contrasts the internal reliability and predictive validity of a basic (general alcohol words) and an upgraded (personalized alcohol pictures) Stroop task delivered in a neutral room on a laptop computer versus a smartphone application on participants' homes. METHODS: 120 participants recruited in 2016, completed a basic and an upgraded Stroop task. Half the participants completed the tasks on a laptop computer in a neutral university room and the remainder completed the tasks on a smartphone app in their homes. Participants also self-reported their typical alcohol consumption. RESULTS: Acceptable internal reliability was found for both basic (α = .70) and upgraded (α = .74) Stroop tasks in the home-smartphone condition, but neither had acceptable internal reliability when administered in the neutral room-computer condition (basic α = .49; upgraded α = .58). Participants showed AB toward alcohol words, but not for beer pictures, regardless of condition. None of the indices of AB was associated with individual differences in alcohol involvement, regardless of condition. CONCLUSION: The internal reliability of the alcohol Stroop was acceptable when administered on smartphones, in naturalistic settings, rather than on laptop computers, in neutral university rooms.


Assuntos
Viés de Atenção , Reprodutibilidade dos Testes , Smartphone , Teste de Stroop , Consumo de Bebidas Alcoólicas/psicologia , Computadores , Feminino , Humanos , Individualidade , Masculino , Aplicativos Móveis , Psicometria , Tempo de Reação , Adulto Jovem
20.
Molecules ; 24(8)2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30991712

RESUMO

Parasitic helminths infect billions of people, livestock, and companion animals worldwide. Recently, they have been explored as a novel therapeutic modality to treat autoimmune diseases due to their potent immunoregulatory properties. While feeding in the gut/organs/tissues, the parasitic helminths actively release excretory-secretory products (ESP) to modify their environment and promote their survival. The ESP proteins of helminths have been widely studied. However, there are only limited studies characterizing the non-protein small molecule (SM) components of helminth ESP. In this study, using GC-MS and LC-MS, we have investigated the SM ESP of tapeworm Dipylidium caninum (isolated from dogs) which accidentally infects humans via ingestion of infected cat and dog fleas that harbor the larval stage of the parasite. From this D. caninum ESP, we have identified a total of 49 SM (35 polar metabolites and 14 fatty acids) belonging to 12 different chemotaxonomic groups including amino acids, amino sugars, amino acid lactams, organic acids, sugars, sugar alcohols, sugar phosphates, glycerophosphates, phosphate esters, disaccharides, fatty acids, and fatty acid derivatives. Succinic acid was the major small molecule present in the D. caninum ESP. Based on the literature and databases searches, we found that of 49 metabolites identified, only 12 possessed known bioactivities.


Assuntos
Doenças do Gato/metabolismo , Cestoides/metabolismo , Infecções por Cestoides/metabolismo , Doenças do Cão/metabolismo , Animais , Doenças do Gato/parasitologia , Gatos , Cromatografia Líquida , Doenças do Cão/parasitologia , Cães , Humanos
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