354 research outputs found
Are genetic risk factors for psychosis also associated with dimension-specific psychotic experiences in adolescence?
Psychosis has been hypothesised to be a continuously distributed quantitative phenotype and disorders such as schizophrenia and bipolar disorder represent its extreme manifestations. Evidence suggests that common genetic variants play an important role in liability to both schizophrenia and bipolar disorder. Here we tested the hypothesis that these common variants would also influence psychotic experiences measured dimensionally in adolescents in the general population. Our aim was to test whether schizophrenia and bipolar disorder polygenic risk scores (PRS), as well as specific single nucleotide polymorphisms (SNPs) previously identified as risk variants for schizophrenia, were associated with adolescent dimension-specific psychotic experiences. Self-reported Paranoia, Hallucinations, Cognitive Disorganisation, Grandiosity, Anhedonia, and Parent-rated Negative Symptoms, as measured by the Specific Psychotic Experiences Questionnaire (SPEQ), were assessed in a community sample of 2,152 16-year-olds. Polygenic risk scores were calculated using estimates of the log of odds ratios from the Psychiatric Genomics Consortium GWAS stage-1 mega-analysis of schizophrenia and bipolar disorder. The polygenic risk analyses yielded no significant associations between schizophrenia and bipolar disorder PRS and the SPEQ measures. The analyses on the 28 individual SNPs previously associated with schizophrenia found that two SNPs in TCF4 returned a significant association with the SPEQ Paranoia dimension, rs17512836 (p-value=2.57x10-4) and rs9960767 (p-value=6.23x10-4). Replication in an independent sample of 16-year-olds (N=3,427) assessed using the Psychotic-Like Symptoms Questionnaire (PLIKS-Q), a composite measure of multiple positive psychotic experiences, failed to yield significant results. Future research with PRS derived from larger samples, as well as larger adolescent validation samples, would improve the predictive power to test these hypotheses further. The challenges of relating adult clinical diagnostic constructs such as schizophrenia to adolescent psychotic experiences at a genetic level are discussed
Melioidosis in people living with diabetes; clinical presentation, clinical course and implications for patient management
Background: Despite the well-established link between diabetes mellitus and melioidosis, the precise impact of diabetes, its complications, and its therapy on the presentation and clinical course of melioidosis is incompletely defined. The influence of glycaemic control on the diverse clinical manifestations and the clinical course of melioidosis in patients with diabetes has also not been examined in detail. Methods: We examined all cases of culture-confirmed melioidosis in Far North Queensland, Australia between October 1, 2016, and April 30, 2024. We hoped to define the impact of diabetes, its control and its therapy on the patients’ presentation and their clinical course. Results: There were 321 cases of culture-confirmed melioidosis during the study period; the patients’ median (interquartile range (IQR)) age was 57 (46–69) years, 212/321 (66 %) were male, 130/321 (41 %) identified as First Nations Australians. Diabetes was the most common risk factor for melioidosis in the cohort (163/321, 51 %); in 19/163 (12 %) this was a new diagnosis. The median (IQR)) glycosylated haemoglobin prior to presentation was 9.1 % (7.2–11.5) and 96/162 (59 %) with complete data had established macrovascular or microvascular complications. People with diabetes were more likely – than people without diabetes – to have involvement of the liver (odds ratio (OR) 95 % confidence interval (CI): 9.68 (2.21–42.46), p = 0.003), the spleen (OR (95 % CI): 7.32 (1.64–32.80), p = 0.009) or to have disseminated disease (OR (95 % CI): 2.93 (1.26–6.78), p = 0.01). However, people with diabetes were no more likely than people without diabetes to require intensive care unit admission (OR (95 % CI): 0.82 (0.47–1.42), p = 0.48) or to die before hospital discharge (12/163 (7 %) versus 19/158 (12 %), OR (95 % CI): 0.58 (0.27–1.24), p = 0.16). Only 58/163 (36 %) with diabetes had specialist endocrinology review during their hospitalisation and only 22/72 (31 %) with accessible data had good glycaemic control (glycosylated haemoglobin ≤7 %) in the 12 months after discharge, increasing their risk of subsequent diabetic complications. Of the 151 people with diabetes surviving their hospitalisation, 26 (17 %) died, at a median (IQR) of 1.0 (0.40–4.1) years after discharge. Of the individuals with diabetes who had completed five years of follow up, 21/60 (35 %) had died at a median (IQR) age of 67 (51–84) years. Conclusions: Individuals with diabetes and melioidosis are more likely to have liver and spleen abscesses and disseminated disease than individuals without diabetes, manifestations that appear to be linked directly to glycaemic control. In Australia's well-resourced health system <10 % of patients with diabetes and melioidosis will die from their infection. However, five-year all-cause mortality in individuals with diabetes who survive their melioidosis is greater than 30 %, emphasising the importance of close, holistic multidisciplinary follow-up to ensure their optimal long-term health outcomes
Differentiating founder and chronic HIV envelope sequences
This is the final version. Available from Public Library of Science via the DOI in this record.The sequence data are available in the Dryad Data Depository. Data package title: Data from: Differentiating founder and chronic HIV envelope sequences Provisional DOI: doi:10.5061/dryad.r19c2 Data files: HIV envelope sequences Seroconverter HIV subtype B envelope sequences.Significant progress has been made in characterizing broadly neutralizing antibodies against the HIV envelope glycoprotein Env, but an effective vaccine has proven elusive. Vaccine development would be facilitated if common features of early founder virus required for transmission could be identified. Here we employ a combination of bioinformatic and operations research methods to determine the most prevalent features that distinguish 78 subtype B and 55 subtype C founder Env sequences from an equal number of chronic sequences. There were a number of equivalent optimal networks (based on the fewest covarying amino acid (AA) pairs or a measure of maximal covariance) that separated founders from chronics: 13 pairs for subtype B and 75 for subtype C. Every subtype B optimal solution contained the founder pairs 178–346 Asn-Val, 232–236 Thr-Ser, 240–340 Lys-Lys, 279–315 Asp-Lys, 291–792 Ala-Ile, 322–347 Asp-Thr, 535–620 Leu-Asp, 742–837 Arg-Phe, and 750–836 Asp-Ile; the most common optimal pairs for subtype C were 644–781 Lys-Ala (74 of 75 networks), 133–287 Ala-Gln (73/75) and 307–337 Ile-Gln (73/75). No pair was present in all optimal subtype C solutions highlighting the difficulty in targeting transmission with a single vaccine strain. Relative to the size of its domain (0.35% of Env), the α4β7 binding site occurred most frequently among optimal pairs, especially for subtype C: 4.2% of optimal pairs (1.2% for subtype B). Early sequences from 5 subtype B pre-seroconverters each exhibited at least one clone containing an optimal feature 553–624 (Ser-Asn), 724–747 (Arg-Arg), or 46–293 (Arg-Glu).University of New South Wales (UNSW) Goldstar Gran
Evaluating the Impact of Functional Genetic Variation on HIV-1 Control
BACKGROUND: Previous genetic association studies of human immunodeficiency virus-1 (HIV-1) progression have focused on
common human genetic variation ascertained through genome-wide genotyping.
METHODS: We sought to systematically assess the full spectrum of functional variation in protein coding gene regions on HIV-1
progression through exome sequencing of 1327 individuals. Genetic variants were tested individually and in aggregate across genes
and gene sets for an influence on HIV-1 viral load.
RESULTS: Multiple single variants within the major histocompatibility complex (MHC) region were observed to be strongly associated
with HIV-1 outcome, consistent with the known impact of classical HLA alleles. However, no single variant or gene located
outside of the MHC region was significantly associated with HIV progression. Set-based association testing focusing on genes identified
as being essential for HIV replication in genome-wide small interfering RNA (siRNA) and clustered regularly interspaced short
palindromic repeats (CRISPR) studies did not reveal any novel associations.
CONCLUSIONS: These results suggest that exonic variants with large effect sizes are unlikely to have a major contribution to host
control of HIV infectio
Host genotype and time dependent antigen presentation of viral peptides: predictions from theory
The rate of progression of HIV infected individuals to AIDS is known to vary with the genotype of the host, and is linked to their allele of human leukocyte antigen (HLA) proteins, which present protein degradation products at the cell surface to circulating T-cells. HLA alleles are associated with Gag-specific T-cell responses that are protective against progression of the disease. While Pol is the most conserved HIV sequence, its association with immune control is not as strong. To gain a more thorough quantitative understanding of the factors that contribute to immunodominance, we have constructed a model of the recognition of HIV infection by the MHC class I pathway. Our model predicts surface presentation of HIV peptides over time, demonstrates the importance of viral protein kinetics, and provides evidence of the importance of Gag peptides in the long-term control of HIV infection. Furthermore, short-term dynamics are also predicted, with simulation of virion-derived peptides suggesting that efficient processing of Gag can lead to a 50% probability of presentation within 3 hours post-infection, as observed experimentally. In conjunction with epitope prediction algorithms, this modelling approach could be used to refine experimental targets for potential T-cell vaccines, both for HIV and other viruses
“We wouldn’t of made friends if we didn’t come to Football United”: the impacts of a football program on young people’s peer, prosocial and cross-cultural relationships
Background
Sport as a mechanism to build relationships across cultural boundaries and to build positive interactions among young people has often been promoted in the literature. However, robust evaluation of sport-for-development program impacts is limited. This study reports on an impact evaluation of a sport-for-development program in Australia, Football United®.
Methods
A quasi-experimental mixed methods design was employed using treatment partitioning (different groups compared had different levels of exposure to Football United). A survey was undertaken with 142 young people (average age of 14.7 years with 22.5% of the sample comprising girls) in four Australian schools. These schools included two Football United and two Comparison schools where Football United was not operating. The survey instrument was composed of previously validated measures, including emotional symptoms, peer problems and relationships, prosocial behaviour, other-group orientation, feelings of social inclusion and belonging and resilience. Face to face interviews were undertaken with a purposeful sample (n = 79) of those who completed the survey. The participants in the interviews were selected to provide a diversity of age, gender and cultural backgrounds.
Results
Young people who participated in Football United showed significantly higher levels of other-group orientation than a Comparison Group (who did not participate in the program). The Football United boys had significantly lower scores on the peer problem scale and significantly higher scores on the prosocial scale than boys in the Comparison Group. Treatment partitioning analyses showed positive, linear associations between other-group orientation and total participation in the Football United program. A lower score on peer problems and higher scores on prosocial behaviour in the survey were associated with regularity of attendance at Football United. These quantitative results are supported by qualitative data analysed from interviews.
Conclusions
The study provides evidence of the effects of Football United on key domains of peer and prosocial relationships for boys and other-group orientation for young people in the program sites studied. The effects on girls, and the impacts of the program on the broader school environment and at the community level, require further investigation
Nanoparticle Delivery Platforms for RNAi Therapeutics Targeting COVID-19 Disease in the Respiratory Tract.
Since December 2019, a pandemic of COVID-19 disease, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has rapidly spread across the globe. At present, the Food and Drug Administration (FDA) has issued emergency approval for the use of some antiviral drugs. However, these drugs still have limitations in the specific treatment of COVID-19, and as such, new treatment strategies urgently need to be developed. RNA-interference-based gene therapy provides a tractable target for antiviral treatment. Ensuring cell-specific targeted delivery is important to the success of gene therapy. The use of nanoparticles (NPs) as carriers for the delivery of small interfering RNA (siRNAs) to specific tissues or organs of the human body could play a crucial role in the specific therapy of severe respiratory infections, such as COVID-19. In this review, we describe a variety of novel nanocarriers, such as lipid NPs, star polymer NPs, and glycogen NPs, and summarize the pre-clinical/clinical progress of these nanoparticle platforms in siRNA delivery. We also discuss the application of various NP-capsulated siRNA as therapeutics for SARS-CoV-2 infection, the challenges with targeting these therapeutics to local delivery in the lung, and various inhalation devices used for therapeutic administration. We also discuss currently available animal models that are used for preclinical assessment of RNA-interference-based gene therapy. Advances in this field have the potential for antiviral treatments of COVID-19 disease and could be adapted to treat a range of respiratory diseases
Circulating gluten-specific, but not CMV-specific, CD39<sup>+</sup> regulatory T cells have an oligoclonal TCR repertoire
Objectives: Understanding the T cell receptor (TCR) repertoire of regulatory CD4+ T-cell (Treg) populations is important for strategies aiming to re-establish tolerance in autoimmune diseases. We studied circulating deamidated gluten-epitope-specific CD39+ Tregs in patients with coeliac disease following an oral gluten challenge, and we used cytomegalovirus (CMV)-specific CD39+ Tregs from healthy controls as a comparator population. Methods: We used the OX40 assay to isolate antigen-specific Tregs by induced surface co-expression of CD25, OX40 and CD39. RACE PCR amplification and Sanger sequencing of the TCR β chain were used to analyse repertoire diversity. Results: We found that, following oral gluten challenge, circulating gluten-specific CD39+ Tregs had an oligoclonal TCR repertoire that contained public clonotypes. Conversely, the TCR repertoire of CMV-epitope-specific CD39+ Tregs from healthy controls was polyclonal. Discussion: These data indicate that a biased TCR repertoire is not inherent to CD39+ Tregs, and, in this case, is apparently driven by the HLA-DQ2.5-restricted deamidated gluten peptide in coeliac disease patients. Conclusion: This is the first assessment of the TCR repertoire within circulating human Tregs specific for foreign antigen. These data enhance our understanding of antigen-specific CD4+ responses in the settings of chronic inflammation and infection and may help guide immunomonitoring strategies for CD4+ T cell-based therapies, particularly for coeliac disease
Most HIV DNA in PBMC is present in non-gut homing, resting memory CD4+ T cells with a ß7-CD38-CD127 high phenotype
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