312 research outputs found
International biological reference preparations for epidemic infectious diseases
Recent years have seen unprecedented investment in research and development for countermeasures for high-threat pathogens, including specific and ambitious objectives for development of diagnostics, therapeutics, and vaccines. The inadequate availability of biological reference materials for these pathogens poses a genuine obstacle in pursuit of these objectives, and the lack of a comprehensive and equitable framework for developing reference materials is a weakness. We outline the need for internationally standardized biological materials for high-threat pathogens as a core element of global health security. We also outline the key components of a framework for addressing this deficiency
Neuroblastoma in monozygotic twins – a case of probable twin-to-twin metastasis
Concordance for neuroblastoma in monozygotic twins has been reported only rarely, and the cause of the shared pathology has not been established. We describe a case of infant monozygotic twins developing tumours that were morphologically, clinically and molecularly indistinguishable, but with a delay of 6 months between times of presentation. Both tumours were metastatic and had amplification of MYCN and deletion at 1p36. Twin 1, who developed neuroblastoma first, had constitutional karyotype abnormalities in at least 5% of peripheral blood mononuclear cells involving 1p and 3p, and a deletion of 1q44 in 21% of cells. Twin 2 had a normal constitutional karyotype and lacked rearrangement or deletion of these regions. We propose an acquired neuroblastoma predisposition specific for twin 1, and in utero metastatic spread of tumour cells to twin 2 via the shared placental circulation. © 2001 Cancer Research Campaign http://www.bjcancer.co
The presence of Y674/Y675 phosphorylated NTRK1 via TP53 repression of PTPN6 expression as a potential prognostic marker in neuroblastoma
The tumor suppressor TP53 promotes nerve growth factor receptor (NTRK1) -Y674/Y675 phosphorylation (NTRK1-pY674/pY675) via repression of the NTRK1 phosphatase PTPN6 in a ligand-independent manner, resulting in suppression of breast cancer cell proliferation. Moreover, NTRK1-pY674/pY675 together with low levels of PTPN6 and TP53 expression is associated with favorable disease-free survival of breast cancer patients. We determined whether in neuroblastoma this protein expression pattern impacts relapse-free survival (RFS). NTRK1-pY674/pY675, PTPN6, and TP53 expression was assessed in 98 neuroblastoma samples by immunohistochemistry. Association between expression levels and RFS was investigated by multivariate and Kaplan-Meier analysis. Mutant or wild-type TP53 was identified by sequencing tumor DNA. Tumors expressing NTRK1-pY674/pY675 and low or undetectable levels of PTPN6 and TP53 were significantly associated with 5-year RFS (P = .014) when the dataset was stratified by MYCN amplification, segmental chromosomal abnormalities and histology. Similar results were observed with tumors expressing wild-type TP53, NTRK1-pY674/pY675 and low or undetectable levels of PTPN6. Kaplan-Meier analysis demonstrated a significant correlation (P = .004), with a 50% probability of RFS (median survival 4.73 years) when present compared with 19.51% (median survival 11.63 months) when absent. Similar results were seen with non-amplified MYCN or unfavorable/undifferentiating samples and tumors from patients aged 18 months or less. Importantly, NTRK1-pY674/pY675 is an independent predictor of improved RFS. These results strongly suggest that NTRK1-pY674/pY675 together with wild-type TP53 and undetectable or low levels of PTPN6 expression is a potential biomarker of improved RFS of neuroblastoma patients. The predictive value of NTRK1-pY674/pY675 together with wild-type TP53 and low PTPN6 expression could contribute to neuroblastoma patient prognosis
Nosocomial Transmission of Coronavirus Disease 2019: A Retrospective Study of 66 Hospital-acquired Cases in a London Teaching Hospital
COVID-19 can cause deadly healthcare-associated outbreaks. In a major London teaching hospital, 66/435 (15%) of COVID-19 inpatient cases between 2 March and 12 April 2020 were definitely or probably hospital-acquired, through varied transmission routes. The case fatality was 36%. Nosocomial infection rates fell following comprehensive infection prevention and control measures
Systematic evaluation and external validation of 22 prognostic models among hospitalised adults with COVID-19: An observational cohort study
Background: The number of proposed prognostic models for COVID-19 is growing rapidly, but it is unknown whether any are suitable for widespread clinical implementation. /
Methods: We independently externally validated the performance candidate prognostic models, identified through a living systematic review, among consecutive adults admitted to hospital with a final diagnosis of COVID-19. We reconstructed candidate models as per original descriptions and evaluated performance for their original intended outcomes using predictors measured at admission. We assessed discrimination, calibration and net benefit, compared to the default strategies of treating all and no patients, and against the most discriminating predictor in univariable analyses. /
Results: We tested 22 candidate prognostic models among 411 participants with COVID-19, of whom 180 (43.8%) and 115 (28.0%) met the endpoints of clinical deterioration and mortality, respectively. Highest areas under receiver operating characteristic (AUROC) curves were achieved by the NEWS2 score for prediction of deterioration over 24 h (0.78; 95% CI 0.73–0.83), and a novel model for prediction of deterioration <14 days from admission (0.78; 0.74–0.82). The most discriminating univariable predictors were admission oxygen saturation on room air for in-hospital deterioration (AUROC 0.76; 0.71–0.81), and age for in-hospital mortality (AUROC 0.76; 0.71–0.81). No prognostic model demonstrated consistently higher net benefit than these univariable predictors, across a range of threshold probabilities. /
Conclusions: Admission oxygen saturation on room air and patient age are strong predictors of deterioration and mortality among hospitalised adults with COVID-19, respectively. None of the prognostic models evaluated here offered incremental value for patient stratification to these univariable predictors
Anti-inflammatory therapy with nebulised dornase alfa in patients with severe COVID-19 pneumonia A Randomised Clinical Trial
BACKGROUND:
SARS-CoV2 infection causes severe, life-threatening pneumonia. Hyper-inflammation, coagulopathy and lymphopenia are associated with pathology and poor outcomes in these patients. Cell-free (cf) DNA is prominent in COVID-19 patients, amplifies inflammation and promotes coagulopathy and immune dysfunction. We hypothesized that cf-DNA clearance by nebulised dornase alfa may reduce inflammation and improve disease outcomes. Here, we evaluated the efficacy of nebulized dornase alfa in patients hospitalised with severe COVID-19 pneumonia.
METHODS:
In this randomised controlled single-centre phase 2 proof-of-concept trial, we recruited adult patients admitted to hospital that exhibited stable oxygen saturation (≥94%) on supplementary oxygen and a C-reactive protein (CRP) level ≥30mg/L post dexamethasone treatment. Participants were randomized at a 3:1 ratio to receive twice-daily nebulised dornase alfa in addition to best available care (BAC) or BAC alone for seven days or until hospital discharge. A 2:1 ratio of historical controls to treated individuals (HC, 2:1) were included as the primary endpoint comparators. The primary outcome was a reduction in systemic inflammation measured by blood CRP levels over 7 days post-randomisation, or to discharge if sooner. Secondary and exploratory outcomes included time to discharge, time on oxygen, D-dimer levels, lymphocyte counts and levels of circulating cf-DNA.
RESULTS:
We screened 75 patients and enrolled 39 participants out of which 30 in dornase alfa arm, and 9 in BAC group. We also matched the recruited patients in the treated group (N=30) to historical controls in the BAC group (N=60). For the the primary outcome, 30 patients in the dornase alfa were compared to 69 patients in the BAC group. Dornase alfa treatment reduced CRP by 33% compared to the BAC group at 7-days (P=0.01). The dornase alfa group least squares mean CRP was 23.23 mg/L (95% CI 17.71 to 30.46) and the BAC group 34.82 mg/L (95% CI 28.55 to 42.47). A significant difference was also observed when only randomised participants were compared. Furthermore, compared to the BAC group, the chance of live discharge was increased by 63% in the dornase alfa group (HR 1.63, 95% CI 1.01 to 2.61, P=0.03), lymphocyte counts were improved (least-square mean: 1.08 vs 0.87, P=0.02) and markers of coagulopathy such as D-dimer were diminished (least-square mean: 570.78 vs 1656.96μg/mL, P=0.004). Moreover, the dornase alfa group exhibited lower circulating cf-DNA levels that correlated with CRP changes over the course of treatment. No differences were recorded in the rates and length of stay in the ICU or the time on oxygen between the groups. Dornase alfa was well-tolerated with no serious adverse events reported.
CONCLUSION:
In this proof-of-concept study in patients with severe COVID-19 pneumonia, treatment with nebulised dornase alfa resulted in a significant reduction in inflammation, markers of immune pathology and time to discharge. The effectiveness of dornase alfa in patients with acute respiratory infection and inflammation should be investigated further in larger trials
Monkeypox virus-infected individuals mount comparable humoral immune responses as Smallpox-vaccinated individuals
In early 2022, a cluster of monkeypox virus (MPXV) infection (mpox) cases were identified within the UK with no prior travel history to MPXV-endemic regions. Subsequently, case numbers exceeding 80,000 were reported worldwide, primarily affecting gay, bisexual, and other men who have sex with men (GBMSM). Public health agencies worldwide have offered the IMVANEX Smallpox vaccination to these individuals at high-risk to provide protection and limit the spread of MPXV. We have developed a comprehensive array of ELISAs to study poxvirus-induced antibodies, utilising 24 MPXV and 3 Vaccinia virus (VACV) recombinant antigens. Panels of serum samples from individuals with differing Smallpox-vaccine doses and those with prior MPXV infection were tested on these assays, where we observed that one dose of Smallpox vaccination induces a low number of antibodies to a limited number of MPXV antigens but increasing with further vaccination doses. MPXV infection induced similar antibody responses to diverse poxvirus antigens observed in Smallpox-vaccinated individuals. We identify MPXV A27 as a serological marker of MPXV-infection, whilst MPXV M1 (VACV L1) is likely IMVANEX-specific. Here, we demonstrate analogous humoral antigen recognition between both MPXV-infected or Smallpox-vaccinated individuals, with binding to diverse yet core set of poxvirus antigens, providing opportunities for future vaccine (e.g., mRNA) and therapeutic (e.g., mAbs) design
Low seropositivity and suboptimal neutralisation rates in patients fully vaccinated against COVID-19 with B-cell malignancies
Generation and Clinical Application of Gene-Modified Autologous Epidermal Sheets in Netherton Syndrome: Lessons Learned from a Phase 1 Trial
Netherton Syndrome (NS) is a rare autosomal recessive skin disorder caused by mutations in SPINK5. It is a debilitating condition with notable mortality in the early years of life. There is no curative treatment. We undertook a non-randomized, open-label, feasibility and safety study using autologous keratinocytes transduced with a lentiviral vector encoding SPINK5 under the control of the human involucrin promoter. Six NS subjects were recruited and gene-modified epithelial sheets were successfully generated in three out of five subjects. The sheets exhibited expression of correctly sized LEKTI protein after modification. One subject was grafted with a 20cm2 gene-modified graft on the left anterior thigh without any adverse complications and was monitored by serial sampling for 12 months. Recovery within the graft area were compared against an area outside by morphology, pro-viral copy number and expression of the SPINK5 encoded protein, LEKTI, and its down-stream target kallikrein 5, which exhibited transient functional correction. The study confirmed the feasibility of generating lentiviral gene-modified epidermal sheets for inherited skin diseases such as NS, but sustained LEKTI expression is likely to require the identification, targeting and engraftment of long-lived keratinocyte stem cell populations for durable therapeutic effects. Important learning points for the application of gene modified epidermal sheets are discussed
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