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1.
Sci Total Environ ; : 176781, 2024 Oct 10.
Article in English | MEDLINE | ID: mdl-39395483

ABSTRACT

Synthetic glucocorticoids (GCs) are used to treat a wide range of human health conditions and as such are frequently detected in the aquatic environment. This, together with the highly conserved nature of the glucocorticoid system across vertebrates means that the potential for biological effects of GCs in fish is relatively high. Here, we found that exposure of zebrafish (Danio rerio) to environmentally relevant concentrations of 4 of the most widely used synthetic GCs (beclomethasone dipropionate, budesonide, fluticasone propionate, and prednisolone), from 0 to 4 days post fertilisation (dpf), resulted in no effects on embryo-larval development or bone and cartilage formation. However, after exposure to equivalents of human therapeutic plasma levels, developmental abnormalities were observed that included pericardial oedema, blood pooling and alterations in jaw cartilage. Furthermore, using a double transgenic zebrafish osteoblast and chondrocyte reporter line, exposure up to 10 dpf resulted in alterations to lower jaw cartilage and bone development for all compounds at, and above, human therapeutic plasma concentrations. In the case of beclomethasone dipropionate, a reduction in lower jaw intercranial distance was observed at the environmentally relevant concentration of 0.1 µg/L. Using further transgenic reporter lines with fluorescently tagged neutrophils and macrophages, we also show exposure of embryo-larvae (0-4 dpf) to the GCs tested resulted in altered immune cell migration, but only at relatively high exposure concentrations. Collectively, our findings show GC exposure impacts embryo-larval zebrafish development, immune function, and skeletal formation, but predominantly at concentrations greater than those currently reported for the aquatic environment. Despite this, however, it is suggested that studies with longer exposure times, and to mixtures of multiple GCs (many GCs act via the same mechanism of action) are warranted before we can confidently assert that these commonly detected contaminants do not pose a risk to fish in the wild.

2.
Sci Total Environ ; 952: 176001, 2024 Nov 20.
Article in English | MEDLINE | ID: mdl-39233069

ABSTRACT

There is growing evidence that rising global temperatures resulting from climate change may exacerbate the toxic effect of pollutants and heterotherms, including fish, in which homestatic mechanisms are directly influenced by environmental temperature will be most affected. Pharmaceuticals discharged into the environment are potentially harmful to wildlife as many of their drug targets are conserved across divergent phyla. Oxidative stress (OS) is a major mechanism by which many pharmaceutical contaminants can induce toxicity but this has received little consideration in the context of effects in wildlife. Further, these mechanisms are relatively poorly understood, particularly regarding multiple stressor interactions. We used transgenic TG(EpRE:mCherry) zebrafish, developed in our laboratory for detecting OS, as our experimental model. We show that the oxidative effects of high concentrations of pharmaceuticals from three different therapeutic classes (paracetamol, diclofenac and doxorubicin) are increased at temperatures elevated by 2-5 °C above those for zebrafish standard husbandry and relevant to their current natural environment (and predicted under the IPCC 2023 scenarios for intermediate to very high greenhouse gas emissions). These OS responses were primarily seen in the pronephros, liver, and gastrointestinal tract. The increase in OS at the increased water temperature may have resulted from the elevated temperature acting as a direct additive physiological stressor to the OS imposed by the drugs and/or via the temperature increasing the chemicals oxidative effect. For paracetamol, it appeared that the elevated responses at the higher temperature of 33 °C were in part due to an increase in uptake of the drug. Our data illustrate that risk assessments for chemicals inducing OS in fish (and likely other heterotherms) should consider the influence of temperature to ensure environmental protection in future environments.


Subject(s)
Larva , Oxidative Stress , Water Pollutants, Chemical , Zebrafish , Zebrafish/physiology , Animals , Water Pollutants, Chemical/toxicity , Larva/drug effects , Climate Change , Hot Temperature/adverse effects , Acetaminophen/toxicity , Diclofenac/toxicity , Temperature
3.
J Hepatol ; 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38986744

ABSTRACT

BACKGROUND & AIMS: An optimal HCV vaccine requires the induction of antibodies that neutralise the infectivity of many heterogenous viral isolates. In this study, we have focused on determining the optimal recombinant envelope glycoprotein component to elicit cross-neutralising antibodies against global HCV genotypes. We compared the immunoreactivity and antigenicity of the HCV genotype 1a strain H77C-derived envelope glycoprotein heterodimer gpE1/gpE2 with that of recombinant gpE2 alone. METHODS: Characterisation of the envelope glycoproteins was accomplished by determining their ability to bind to a panel of broadly cross-neutralising monoclonal antibodies. Immunogenicity was determined by testing the ability of vaccine antisera to neutralise the infectivity in vitro of a panel of pseudotyped HCV particles in which gpE1/gpE2 derived from representative isolates of the major global HCV genotypes were displayed. RESULTS: gpE1/gpE2 binds to more diverse broadly cross-neutralising antibodies than gpE2 alone and elicits a broader profile of cross-neutralising antibodies in animals, especially against more heterologous, non-1a genotypes. While not all heterologous HCV strains can be potently inhibited in vitro by gpE1/gpE2 antisera derived from a single HCV strain, the breadth of heterologous cross-neutralisation is shown to be substantial. CONCLUSIONS: Our work supports the inclusion of gpE1/gpE2 in an HCV vaccine in order to maximise the cross-neutralisation of heterogenous HCV isolates. Our data also offers future directions in formulating a cocktail of gpE1/gpE2 antigens from a small selection of HCV genotypes to further enhance cross-neutralisation of global HCV strains and hopefully advance the development of a globally effective HCV vaccine. IMPACT AND IMPLICATIONS: An HCV vaccine is urgently required to prevent the high global incidence of HCV infection and disease. Since HCV is a highly heterogeneous virus, it is desirable for a vaccine to elicit antibodies that neutralise the infectivity of most global strains. To this end, we have compared the immunoreactivity and antigenicity of recombinant H77C E1E2 heterodimer with that of H77C E2 alone and show that the former exhibits more cross-neutralising epitopes and demonstrates a broader cross-neutralisation profile in vitro. In addition, our data suggests a way to further broaden cross-neutralisation using a combination of E1E2 antigens derived from a few different HCV clades. Our work is relevant for the development of an effective global HCV vaccine.

4.
J Surg Res ; 300: 183-190, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38823268

ABSTRACT

INTRODUCTION: Literature shows failure of the outpatient clinic (OC) pathway after emergency department (ED) ultrasound diagnosis of symptomatic cholelithiasis (SC). We hypothesized SC to be more prevalent on final surgical pathology (FSP) in patients who successfully completed OC pathway. METHODS: This retrospective single-institution chart review compared OC and ED patients with right upper quadrant (RUQ) pain and cholelithiasis whom underwent cholecystectomy. Clinical evaluation was considered positive if RUQ pain >4 h, or + Murphy's sign. Ultrasound was positive if two of these three were present: sonographic Murphy's, wall thickness > 4 mm, or pericholecystic fluid. Results were compared with FSP. RESULTS: Six hundred-seven patients underwent cholecystectomy, 299 OC and 308 ED. OC was more likely to SC (23% versus 4.6%) (P < 0.0001) and ED acute cholecystitis (39.3% versus 4.7%). Chronic cholecystitis was the most common FSP in both OC (72%) and ED (56%) populations, of these, 73% of OC denied pain >4 h versus only 10% of ED (P < 0.001). Median time from evaluation to cholecystectomy was 14 d versus 14 h in the OC and ED respectively (P < 0.0001). CONCLUSIONS: While chronic cholecystitis was the most common FSP in both OC and ED, the majority of OC reported RUQ pain <4 h delineating these presentations. Duration of pain should be utilized as algorithm triage. We recommend patients with pain episode <4 h should complete OC algorithm with expedited cholecystectomy within 14 d.


Subject(s)
Ambulatory Care Facilities , Cholecystectomy , Cholelithiasis , Emergency Service, Hospital , Humans , Retrospective Studies , Female , Male , Emergency Service, Hospital/statistics & numerical data , Cholecystectomy/statistics & numerical data , Middle Aged , Adult , Cholelithiasis/surgery , Cholelithiasis/diagnosis , Cholelithiasis/complications , Cholelithiasis/diagnostic imaging , Ambulatory Care Facilities/statistics & numerical data , Ambulatory Care Facilities/organization & administration , Aged , Ultrasonography
5.
Reprod Toxicol ; 127: 108615, 2024 08.
Article in English | MEDLINE | ID: mdl-38815770

ABSTRACT

Zebrafish embryo assays are used by pharmaceutical and chemical companies as new approach methodologies (NAMs) in developmental toxicity screening. Despite an overall high concordance of zebrafish embryo assays with in vivo mammalian studies, false negative and false positive results have been reported. False negative results in risk assessment models are of particular concern for human safety, as developmental anomalies may be missed. Interestingly, for several chemicals and drugs that were reported to be false negative in zebrafish, skeletal findings were noted in the in vivo studies. As the number of skeletal endpoints assessed in zebrafish is very limited compared to the in vivo mammalian studies, the aim of this study was to investigate whether the sensitivity could be increased by including a skeletal staining method. Three staining methods were tested on zebrafish embryos that were exposed to four teratogens that caused skeletal anomalies in rats and/or rabbits and were false negative in zebrafish embryo assays. These methods included a fixed alizarin red-alcian blue staining, a calcein staining, and a live alizarin red staining. The results showed a high variability in staining intensity of larvae exposed to mammalian skeletal teratogens, as well as variability between control larvae originating from the same clutch of zebrafish. Hence, biological variability in (onset of) bone development in zebrafish hampers the detection of (subtle) treatment-related bone effects that are not picked-up by gross morphology. In conclusion, the used skeletal staining methods did not increase the sensitivity of zebrafish embryo developmental toxicity assays.


Subject(s)
Embryo, Nonmammalian , Teratogens , Toxicity Tests , Zebrafish , Animals , Zebrafish/embryology , Teratogens/toxicity , Embryo, Nonmammalian/drug effects , Toxicity Tests/methods , Staining and Labeling , Bone and Bones/drug effects , Bone and Bones/abnormalities , Embryonic Development/drug effects , Fluoresceins/toxicity , Anthraquinones/toxicity
7.
PLoS Pathog ; 20(1): e1011911, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38206964

ABSTRACT

The discrepancy between short- and long-term rate estimates, known as the time-dependent rate phenomenon (TDRP), poses a challenge to extrapolating evolutionary rates over time and reconstructing evolutionary history of viruses. The TDRP reveals a decline in evolutionary rate estimates with the measurement timescale, explained empirically by a power-law rate decay, notably observed in animal and human viruses. A mechanistic evolutionary model, the Prisoner of War (PoW) model, has been proposed to address TDRP in viruses. Although TDRP has been studied in animal viruses, its impact on plant virus evolutionary history remains largely unexplored. Here, we investigated the consequences of TDRP in plant viruses by applying the PoW model to reconstruct the evolutionary history of sobemoviruses, plant pathogens with significant importance due to their impact on agriculture and plant health. Our analysis showed that the Sobemovirus genus dates back over four million years, indicating an ancient origin. We found evidence that supports deep host jumps to Poaceae, Fabaceae, and Solanaceae occurring between tens to hundreds of thousand years ago, followed by specialization. Remarkably, the TDRP-corrected evolutionary history of sobemoviruses was extended far beyond previous estimates that had suggested their emergence nearly 9,000 years ago, a time coinciding with the Neolithic period in the Near East. By incorporating sequences collected through metagenomic analyses, the resulting phylogenetic tree showcases increased genetic diversity, reflecting a deep history of sobemovirus species. We identified major radiation events beginning between 4,600 to 2,000 years ago, which aligns with the Neolithic period in various regions, suggesting a period of rapid diversification from then to the present. Our findings make a case for the possibility of deep evolutionary origins of plant viruses.


Subject(s)
Plant Viruses , RNA Viruses , Animals , Humans , Phylogeny , Biological Evolution , RNA Viruses/genetics , Plant Viruses/genetics , Plants , Evolution, Molecular
8.
Thorax ; 79(1): 75-82, 2023 12 15.
Article in English | MEDLINE | ID: mdl-37657925

ABSTRACT

BACKGROUND: Invasive pulmonary aspergillosis is a complication of severe COVID-19, with regional variation in reported incidence and mortality. We describe the incidence, risk factors and mortality associated with COVID-19-associated pulmonary aspergillosis (CAPA) in a prospective, multicentre UK cohort. METHODS: From March 2020 to March 2021, 266 mechanically ventilated adults with COVID-19 were enrolled across 5 UK hospital intensive care units (ICUs). CAPA was defined using European Confederation for Medical Mycology and the International Society for Human and Animal Mycology criteria and fungal diagnostics performed on respiratory and serum samples. RESULTS: Twenty-nine of 266 patients (10.9%) had probable CAPA, 14 (5.2%) possible CAPA and none proven CAPA. Probable CAPA was diagnosed a median of 9 (IQR 7-16) days after ICU admission. Factors associated with probable CAPA after multivariable logistic regression were cumulative steroid dose given within 28 days prior to ICU admission (adjusted OR (aOR) 1.16; 95% CI 1.01 to 1.43 per 100 mg prednisolone-equivalent), receipt of an interleukin (IL)-6 inhibitor (aOR 2.79; 95% CI 1.22 to 6.48) and chronic obstructive pulmonary disease (COPD) (aOR 4.78; 95% CI 1.13 to 18.13). Mortality in patients with probable CAPA was 55%, vs 46% in those without. After adjustment for immortal time bias, CAPA was associated with an increased risk of 90-day mortality (HR 1.85; 95% CI 1.07 to 3.19); however, this association did not remain statistically significant after further adjustment for confounders (adjusted HR 1.57; 95% CI 0.88 to 2.80). There was no difference in mortality between patients with CAPA prescribed antifungals (9 of 17; 53%) and those who were not (7 of 12; 58%) (p=0.77). INTERPRETATION: In this first prospective UK study, probable CAPA was associated with corticosteroid use, receipt of IL-6 inhibitors and pre-existing COPD. CAPA did not impact mortality following adjustment for prognostic variables.


Subject(s)
COVID-19 , Pulmonary Aspergillosis , Pulmonary Disease, Chronic Obstructive , Adult , Animals , Humans , COVID-19/complications , Prospective Studies , Respiration, Artificial/adverse effects , Pulmonary Aspergillosis/epidemiology , United Kingdom/epidemiology
9.
J Spinal Cord Med ; : 1-8, 2023 Sep 14.
Article in English | MEDLINE | ID: mdl-37707355

ABSTRACT

INTRODUCTION: Interventions provided in the early phases after spinal cord injury (SCI) may improve neurological recovery and provide for best possible functional outcomes. Knowing this relies on early and clear documentation of the level and grade of the spinal cord injury. Guidelines advocate for early documentation of neurological status within 72 h of injury to allow early prognostication and to help guide initial management. It is unclear whether this is current practice in New South Wales (NSW). METHODS: Patients with acute SCI who were admitted to two SCI referral centers during 2018-2019 in NSW were included. Data relating to documentation of neurological status, timing of imaging, surgery and transfer to spinal cord injury center were collected and summarized using descriptive statistics. RESULTS: Only 18 percent of patients had an acceptable neurological examination according to the International Standards for Classification of Spinal Cord Injury (ISNCSCI) within 72 h of injury (either not done, or unable to determine the neurological level of injury). At the first neurological examination, the neurological level of injury and grade was unable to be determined in 26.8% of patients and 29.9% of patients respectively. At discharge from acute care and transfer to rehabilitation, the neurological level was undetermined in 28.9% of patients and grade undetermined in 26.8%. ISNCSCI examination was most commonly performed by spinal rehabilitation doctors after patients were discharged from the intensive care unit (ICU). CONCLUSIONS: Documentation of neurological level and grade of SCI within 72 h of injury is not being performed in the large majority of this cohort, which may impede evaluation of neurological improvement in response to acute treatment, and hinder prognostication.

10.
Am J Surg ; 226(6): 835-839, 2023 12.
Article in English | MEDLINE | ID: mdl-37481409

ABSTRACT

BACKGROUND: The majority of final surgical pathology (FSP) from both emergency department (ED) and outpatient clinic (OC) patients is chronic cholecystitis. We aimed to differentiate these presentations and identify disparities associated with ED utilization and OC failure. METHODS: Retrospective chart review of single institution ED and OC cholecystectomies for cholelithiasis. Clinical presentation, FSP, demographics, and zip code poverty (ZCP) levels were evaluated. Data analysis by summary statistics, bivariate comparisons, and logistic regression. RESULTS: Of 299 OC and 308 ED patients, OC was more likely to be Caucasian (78% vs 46%, p < 0.0001) and insured (89% vs. 32%, p < 0.0001). 71.8% of OC with ZCP <10% had insurance versus only 32.5% in ZCP >20%. Uninsured ED OR was 13.1 (95% CI 8.7-22.9). CONCLUSION: Uninsured ED patients are vulnerable to fail the outpatient algorithm, especially when misdiagnosed by US. Clinical diagnosis of cholecystitis in this population should warrant offering of urgent cholecystectomy.


Subject(s)
Cholecystitis , Outpatients , Humans , Retrospective Studies , Cholecystitis/diagnosis , Cholecystitis/surgery , Cholecystectomy , Emergency Service, Hospital
11.
J Surg Educ ; 80(11): 1682-1686, 2023 11.
Article in English | MEDLINE | ID: mdl-37357106

ABSTRACT

PURPOSE: Emergency department (ED) wait times and ED length of stay (LOS) have a significant impact on patient morbidity and mortality and patient satisfaction. Consultation-to-decision time can contribute to increased wait times and LOS in the ED. Up to 40% of patients presenting to the ED require consultation from subspecialty services. We hypothesize that in surgical patients, completion of workup prior to consultation will decrease consultation-to-decision time, ED wait times, and LOS in the ED. METHODS: A retrospective review was conducted at a single site including all overnight general surgery consultations from the ED over 2-months. Data collected included wait times, LOS, and workup completed prior to consultation. Summary statistics were calculated and bivariate tests were performed using t-tests for continuous variables. RESULTS: Time to final surgical plan and LOS in ED were evaluated for 137 patients comparing "complete" and "incomplete" workups at time of consultation. It was considered a "complete" workup if labs and imaging were resulted prior to time of consult. If any baseline tests were not ordered prior to time of consult, it was considered an "incomplete" workup. Analysis demonstrated an average time of 4.9 and 2.5 hours for consultation-to-decision time for "incomplete" and "complete" workups respectively (p < 0.0001). For LOS in ED, there was an average of 11.4 and 7.9 hours for "incomplete" and "complete" workups respectively (p < 0.0001). CONCLUSIONS: There is a significant difference in consultation-to-decision time and LOS in the ED when consultation is performed following a complete versus incomplete workup for surgical patients independent of inherent wait times for testing to result and the need for additional testing requested from consulting services. Developing strategies to optimize workups from the ED prior to surgical consultation, including the development of care pathways, could significantly decrease patient wait times and LOS in the ED.


Subject(s)
Emergency Service, Hospital , Referral and Consultation , Humans , Prospective Studies , Retrospective Studies , Length of Stay
12.
Proc Natl Acad Sci U S A ; 120(24): e2220294120, 2023 06 13.
Article in English | MEDLINE | ID: mdl-37276424

ABSTRACT

A hepatitis C virus (HCV) vaccine is urgently needed. Vaccine development has been hindered by HCV's genetic diversity, particularly within the immunodominant hypervariable region 1 (HVR1). Here, we developed a strategy to elicit broadly neutralizing antibodies to HVR1, which had previously been considered infeasible. We first applied a unique information theory-based measure of genetic distance to evaluate phenotypic relatedness between HVR1 variants. These distances were used to model the structure of HVR1's sequence space, which was found to have five major clusters. Variants from each cluster were used to immunize mice individually, and as a pentavalent mixture. Sera obtained following immunization neutralized every variant in a diverse HCVpp panel (n = 10), including those resistant to monovalent immunization, and at higher mean titers (1/ID50 = 435) than a glycoprotein E2 (1/ID50 = 205) vaccine. This synergistic immune response offers a unique approach to overcoming antigenic variability and may be applicable to other highly mutable viruses.


Subject(s)
Hepacivirus , Hepatitis C , Animals , Mice , Viral Envelope Proteins/genetics , Immunization , Immunity , Hepatitis C Antibodies , Antibodies, Neutralizing
13.
IJID Reg ; 6: 171-176, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36915800

ABSTRACT

Background: Arboviruses are endemic in Uganda; however, little is known about their epidemiology, seasonality and spatiotemporal distribution. Our study sought to provide information on arbovirus outbreaks from acute clinical presentations. Methods: Immunoglobulin M (IgM) and confirmatory Plaque Reduction Neutralisation Test (PRNT) results for arbovirus diagnosis of samples collected from patients attending sentinel sites from 2016-19 were analysed retrospectively. Demographic data were analysed with SaTScan and SPSS software to determine the epidemiology and spatiotemporal distribution of arboviruses. Results: Arbovirus activity peaked consistently during March-May rainy seasons. Overall, arbovirus seroprevalence was 9.5%. Of 137 IgM positives, 52.6% were confirmed by PRNT, of which 73.6% cases were observed in central Uganda with Yellow Fever Virus had the highest prevalence (27.8%). The 5-14 age group were four times more likely to be infected with an arbovirus p=0.003, 4.1 (95% CI 1.3-12.3). Significant arboviral activity was observed among outdoor workers(p=0.05) . Spatiotemporal analysis indicated arboviral activity in 23 of the 85 districts analysed.. Interpretation: Our study shows that arbovirus activity peaks during the March-May rainy season and highlights the need for YFV mass vaccination to reduce the clinical burden of arboviruses transmitted within the region.

15.
J Med Virol ; 95(1): e28178, 2023 01.
Article in English | MEDLINE | ID: mdl-36168235

ABSTRACT

BACKGROUND AND AIMS: The newly developed direct-acting antivirals have revolutionized the treatment of chronic hepatitis C virus (HCV), with cure rates as high as 98% in some cohorts. Although genome sequencing has demonstrated that some subtypes of HCV naturally harbor drug resistance associated substitutions (RAS), these are often overlooked as "rarities." Furthermore, commercial subtyping assays and associated epidemiological findings are skewed towards Western cohorts and whole-genome sequencing can be problematic to deploy without significant infrastructure and training support. We thus aimed to develop a simple, robust and accurate HCV subtyping pipeline, to optimize and streamline molecular detection and sequence-based typing of diverse RAS-containing subtypes. METHODS: HCV serum derived from 146 individuals, whose likely source of infection was from sub-Saharan Africa (SSA) was investigated with a novel panel of single round polymerase chain reaction (PCR) assays targeting NS5B and NS5A genomic regions. Virus subtype assignments were determined by pairwise-distance analysis and compared to both diagnostic laboratory assignments and free-to-use online typing tools. RESULTS: Partial NS5A and NS5B sequences were respectively obtained from 131 to 135 HCV-positive patients born in 19 different countries from SSA but attending clinics in the UK. We determined that routine clinical diagnostic methods incorrectly subtyped 59.0% of samples, with a further 6.8% incorrectly genotyped. Of five commonly used online tools, Geno2Pheno performed most effectively in determining a subtype in agreement with pairwise distance analysis. CONCLUSION: This study provides a simple low-cost pathway to accurately subtype in SSA, guide regional therapeutic choice and assist global surveillance and elimination initiatives.


Subject(s)
Hepatitis C, Chronic , Hepatitis C , Humans , Hepatitis C, Chronic/diagnosis , Hepatitis C, Chronic/drug therapy , Hepatitis C, Chronic/epidemiology , Antiviral Agents/therapeutic use , Antiviral Agents/pharmacology , Viral Nonstructural Proteins/genetics , Hepatitis C/diagnosis , Hepatitis C/drug therapy , Hepatitis C/epidemiology , Hepacivirus/genetics , Genotype , Africa South of the Sahara/epidemiology , United Kingdom/epidemiology , Drug Resistance, Viral/genetics
16.
J Med Virol ; 95(1): e28331, 2023 01.
Article in English | MEDLINE | ID: mdl-36415047

ABSTRACT

Analysis of host genetic polymorphisms is an increasingly important tool for understanding and predicting pathogenesis and treatment response of viral diseases. The gene locus of scavenger receptor class B type I (SR-BI), encoding a cell entry factor and receptor for hepatitis C virus (HCV), contains several genetic polymorphisms. We applied a probe extension assay to determine the frequency of six single nucleotide polymorphisms (SNPs) within the SR-BI gene locus in 374 individuals with history of HCV infection. In addition, SR-BI messenger RNA (mRNA) levels were analyzed in liver biopsy specimens of chronically infected HCV subjects. The rs5888 variant allele T was present at a higher frequency in subjects with advanced fibrosis (χ2 , p = 0.016) and after adjusting for age, duration of infection and alcohol intake as confounding factors. Haplotype analysis of SNP frequencies showed that a haplotype consisting of rs61932577 variant allele C and rs5888 variant allele T was associated with an increased risk of advanced liver fibrosis (defined by an Ishak score 4-6) (adjusted odds ratio 2.81; 95% confidence interval 1.06-7.46. p = 0.038). Carriers of the rs5888 variant allele T displayed reduced SR-BI mRNA expression in liver biopsy specimens. In conclusion the rs5888 polymorphism variant is associated with decreased SR-BI expression and an increased risk of development of advanced fibrosis in chronic HCV infection. These findings provide further evidence for a role of SR-BI in HCV pathogenesis and provides a genetic marker for prediction of those infected individuals at greater risk of developing severe disease.


Subject(s)
Hepatitis C, Chronic , Scavenger Receptors, Class B , Humans , Hepacivirus/metabolism , Hepatitis C, Chronic/complications , Hepatitis C, Chronic/genetics , Patient Acuity , RNA, Messenger/metabolism , Scavenger Receptors, Class B/metabolism
17.
J Gen Virol ; 103(11)2022 11.
Article in English | MEDLINE | ID: mdl-36399377

ABSTRACT

A better understanding of the antibody response during natural infection and the effect on disease progression and reinfection is necessary for the development of a protective hepatitis C virus (HCV) vaccine. The HCV pseudoparticle (HCVpp) system enables the study of viral entry and inhibition by antibody neutralization. A robust and comparable neutralization assay is crucial for the development and evaluation of experimental vaccines.With the aim of optimizing the HCVpp-murine leukaemia virus (MLV) system, we tested the neutralization of HCVpp-harbouring E1E2 from 21 HCV isolates representing 6 different genotypes by several monoclonal antibodies (mAbs). HCVpps are generated by expressing functional envelope glycoproteins (E1E2) onto pseudoparticles derived from env-deleted MLV. Adjustments of E1E2, gag-pol and luciferase plasmid ratios resulted in increased yields for most HCVpps and recovery of one non-infectious HCVpp. We simplified and improved the protocol to achieve higher signal/noise ratios and minimized the amount of HCVpps and mAbs needed for the detection of neutralization. Using our optimized protocol, we demonstrated comparable results to previously reported data with both diluted and freeze-thawed HCVpps.In conclusion, we successfully established a simplified and reproducible HCVpp neutralization protocol for studying a wide range of HCV variants. This simplified protocol provides highly consistent results and could be easily adopted by others to evaluate precious biological material. This will contribute to a better understanding of the antibody response during natural infection and help evaluate experimental HCV vaccines.


Subject(s)
Hepatitis C , Vaccines , Animals , Mice , Hepacivirus , Antibodies, Neutralizing , Hepatitis C Antibodies , Neutralization Tests , Viral Envelope Proteins/genetics , Hepatitis C/genetics , Antibodies, Monoclonal
18.
Article in English | MEDLINE | ID: mdl-36231764

ABSTRACT

The aim of the study was to explore workforce experiences of the rapid implementation of a SARS-CoV-2 asymptomatic testing service (ATS) in a higher education setting during the COVID-19 pandemic. The setting was a multi-campus university in the UK, which hosted a testing service for employees and students over two years. Qualitative semi-structured videoconference interviews were conducted. We contacted 58 participants and 25 were interviewed (43% response rate). Data were analysed thematically. The analysis produced four overarching themes: (1) feelings relating to their involvement in the service, (2) perceptions of teamwork, (3) perceptions of ATS leadership, (4) valuing the opportunity for career development. Agile and inclusive leadership style created psychological safety and team cohesion, which facilitated participants in the implementation of a rapid mitigation service, at pace and scale. Specific features of the ATS (shared vision, collaboration, networking, skills acquisition) instilled self-confidence, value and belonging, meaningfully impacting on professional development and career opportunities. This is the first qualitative study to explore the experiences of university employees engaged in the rapid deployment of a service as part of a pandemic outbreak and mitigation strategy within a higher education setting. Despite pressures and challenges of the task, professional growth and advancement were universal. This has implications for workforce engagement and creating workplaces across the sector that are well-prepared to respond to future pandemics and other disruptive events.


Subject(s)
COVID-19 , SARS-CoV-2 , COVID-19/diagnosis , COVID-19/epidemiology , Humans , Pandemics , Qualitative Research , Workforce
20.
Article in English | MEDLINE | ID: mdl-36293719

ABSTRACT

Asymptomatic testing for SARS-CoV-2 RNA has been used to prevent and manage COVID-19 outbreaks in university settings, but few studies have explored their implementation. The aim of the study was to evaluate how an accredited asymptomatic SARS-CoV-2 testing service (ATS) was implemented at the University of Nottingham, a multi-campus university in England, to identify barriers and enablers of implementation and to draw out lessons for implementing pandemic response initiatives in higher education settings. A qualitative interview study was conducted with 25 ATS personnel between May and July 2022. Interviews were conducted online, audio-recorded, and transcribed. Participants were asked about their experience of the ATS, barriers and enablers of implementation. Transcripts were thematically analysed. There were four overarching themes: (1) social responsibility and innovation, (2) when, how and why people accessed testing, (3) impact of the ATS on the spread of COVID-19, and (4) lessons learned for the future. In establishing the service, the institution was seen to be valuing its community and socially responsible. The service was viewed to be broadly successful as a COVID-19 mitigation approach. Challenges to service implementation were the rapidly changing pandemic situation and government advice, delays in service accreditation and rollout to staff, ambivalence towards testing and isolating in the target population, and an inability to provide follow-up support for positive cases within the service. Facilitators included service visibility, reduction in organisational bureaucracy and red tape, inclusive leadership, collaborative working with regular feedback on service status, flexibility in service delivery approaches and simplicity of saliva testing. The ATS instilled a perception of early 'return to normality' and impacted positively on staff feelings of safety and wellbeing, with wider benefits for healthcare services and local communities. In conclusion, we identified common themes that have facilitated or hindered the implementation of a SARS-CoV-2 testing service at a university in England. Lessons learned from ATS implementation will inform future pandemic response interventions in higher education settings.


Subject(s)
COVID-19 , Humans , COVID-19/diagnosis , COVID-19/epidemiology , COVID-19/prevention & control , SARS-CoV-2 , COVID-19 Testing , RNA, Viral , England/epidemiology
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