47 research outputs found
Adenovirus DNA in Guthrie cards from children who develop acute lymphoblastic leukaemia (ALL)
Aims: The aim of this thesis was to increase understanding of how molecular processes influence
the development and risk assessment of childhood leukemia. Studies I and II investigates whether a
specific virus infection in utero could be involved in a “first hit” in leukemogenesis. Studies III and
IV examine whether alterations in protein expression from cell cycle regulating genes may predict
a relapse in children with myeloid malignancies undergoing hematopoietic stem cell
transplantation (HSCT).
Background: Genetic alterations, analyzed at time of diagnosis in children who develop leukemia,
have been traced back to neonatal dried blood spots (DBS). This suggests that the majority of
chromosome translocations occur in utero during fetal hematopoiesis, generating a “first hit”. A
“second hit” is then required to generate a leukemic clone. Today, experiments in vitro, animal
models, and clinical observations have revealed that several viruses are oncogenic and capable of
initiating a genetic alteration. Smith M postulated the theory that an in utero infection might be the
“first hit”, causing genetic aberrations that could later lead to the development of the leukemic
clone, which is supported by the early age of onset and space-time clustering data, based on time,
place of birth, and diagnosis.
Leukemia develops as a result of hematopoietic or lymphoid tissue with uncontrolled cell division.
Normally cell division is controlled by the cell cycle, the network of which is complex with
numerous regulating proteins both up and down stream, but also containing several feedback
loops. The important regulators of this process are tumor suppressor genes, essential for normal
cell proliferation and differentiation as well as for controlling DNA integrity. Errors in these genes
or their protein expression affect the ability of the cell to check for DNA damage, thus tumors may
occur. Proteins from these genes could serve as prognostic markers and predict relapse.
Methods: In studies I and II we investigated neonatal DBS by PCR for the presence of adenovirus
DNA (243 samples) and the three newly discovered polyomaviruses (50 samples) from children
who later developed leukemia but also from controls (486 and 100 samples respectively). In
studies III and IV we explored the expression of one (p53) respectively four (p53, p21, p16 and
PTEN) cell cycle regulating proteins in bone marrow at diagnosis as well as pre and post HSCT in
myeloid malignancies in children. We retrospectively collected clinical data and bone marrow
samples from 33 children diagnosed with chronic myeloid malignancies (MDS, JMML and CML),
34 children diagnosed with AML as well as 55 controls. The samples were prepared by tissue
micro array (TMA) as well as immunohistochemistry and examined for protein expression in a
light microscope.
Results: In study I we detected adenovirus DNA in only two patients who later developed
leukemia, but in none of the controls. In study II all the samples were negative for KIPyV, WUPyV
and MCPyV DNA in both patients and controls. In study III we found an overexpression of p53
protein at diagnosis that significantly predicted relapse after HSCT in children with rare chronic
myeloid malignancies. In study IV a significantly higher p53 expression was found in the relapse
compared to the non-relapse group at six months post HSCT in children with AML, suggesting
that p53 may be used as prognostic markers for predicting a relapse. In addition, the calculated cut
off level for p53 at diagnosis (study III) and at six months (study IV) post HSCT was
approximately 20%, which indicates that a p53 expression over 20% may predict relapse in
children with myeloid malignancies.
Conclusion: Although we did not find an association between adenoviruses or the three newly
discovered polyomaviruses and the development of childhood leukemia, a virus could still be
involved in this process; the virus may have escaped detection, other new viruses could be
involved or a virus could precipitate the “second hit”.
We suggest that evaluation of p53 protein expression may be used as a supplement to regular
prognostic markers both pre and post HSCT. To further evaluate this, a prospective multicenter
study has been started
The production of hydroxyapatite prototypes from solid bodies of gypsum/polyvinyl alcohol composites
Abatacept in individuals at high risk of rheumatoid arthritis (APIPPRA): a randomised, double-blind, multicentre, parallel, placebo-controlled, phase 2b clinical trial
\ua9 2024 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Background: Individuals with serum antibodies to citrullinated protein antigens (ACPA), rheumatoid factor, and symptoms, such as inflammatory joint pain, are at high risk of developing rheumatoid arthritis. In the arthritis prevention in the pre-clinical phase of rheumatoid arthritis with abatacept (APIPPRA) trial, we aimed to evaluate the feasibility, efficacy, and acceptability of treating high risk individuals with the T-cell co-stimulation modulator abatacept. Methods: The APIPPRA study was a randomised, double-blind, multicentre, parallel, placebo-controlled, phase 2b clinical trial done in 28 hospital-based early arthritis clinics in the UK and three in the Netherlands. Participants (aged ≥18 years) at risk of rheumatoid arthritis positive for ACPA and rheumatoid factor with inflammatory joint pain were recruited. Exclusion criteria included previous episodes of clinical synovitis and previous use of corticosteroids or disease-modifying antirheumatic drugs. Participants were randomly assigned (1:1) using a computer-generated permuted block randomisation (block sizes of 2 and 4) stratified by sex, smoking, and country, to 125 mg abatacept subcutaneous injections weekly or placebo for 12 months, and then followed up for 12 months. Masking was achieved by providing four kits (identical in appearance and packaging) with pre-filled syringes with coded labels of abatacept or placebo every 3 months. The primary endpoint was the time to development of clinical synovitis in three or more joints or rheumatoid arthritis according to American College of Rheumatology and European Alliance of Associations for Rheumatology 2010 criteria, whichever was met first. Synovitis was confirmed by ultrasonography. Follow-up was completed on Jan 13, 2021. All participants meeting the intention-to-treat principle were included in the analysis. This trial was registered with EudraCT (2013–003413–18). Findings: Between Dec 22, 2014, and Jan 14, 2019, 280 individuals were evaluated for eligibility and, of 213 participants, 110 were randomly assigned to abatacept and 103 to placebo. During the treatment period, seven (6%) of 110 participants in the abatacept group and 30 (29%) of 103 participants in the placebo group met the primary endpoint. At 24 months, 27 (25%) of 110 participants in the abatacept group had progressed to rheumatoid arthritis, compared with 38 (37%) of 103 in the placebo group. The estimated proportion of participants remaining arthritis-free at 12 months was 92\ub78% (SE 2\ub76) in the abatacept group and 69\ub72% (4\ub77) in the placebo group. Kaplan–Meier arthritis-free survival plots over 24 months favoured abatacept (log-rank test p=0\ub7044). The difference in restricted mean survival time between groups was 53 days (95% CI 28–78; p<0\ub70001) at 12 months and 99 days (95% CI 38–161; p=0\ub70016) at 24 months in favour of abatacept. During treatment, abatacept was associated with improvements in pain scores, functional wellbeing, and quality-of-life measurements, as well as low scores of subclinical synovitis by ultrasonography, compared with placebo. However, the effects were not sustained at 24 months. Seven serious adverse events occurred in the abatacept group and 11 in the placebo group, including one death in each group deemed unrelated to treatment. Interpretation: Therapeutic intervention during the at-risk phase of rheumatoid arthritis is feasible, with acceptable safety profiles. T-cell co-stimulation modulation with abatacept for 12 months reduces progression to rheumatoid arthritis, with evidence of sustained efficacy beyond the treatment period, and with no new safety signals. Funding: Bristol Myers Squibb
Non-classical forms of pemphigus: pemphigus herpetiformis, IgA pemphigus, paraneoplastic pemphigus and IgG/IgA pemphigus
The pemphigus group comprises the autoimmune intraepidermal blistering diseases classically divided into two major types: pemphigus vulgaris and pemphigus foliaceous. Pemphigus herpetiformis, IgA pemphigus, paraneoplastic pemphigus and IgG/IgA pemphigus are rarer forms that present some clinical, histological and immunopathological characteristics that are different from the classical types. These are reviewed in this article. Future research may help definitively to locate the position of these forms in the pemphigus group, especially with regard to pemphigus herpetiformis and the IgG/ IgA pemphigus.Universidade Federal de São Paulo (UNIFESP), Escola Paulista de Medicina (EPM) Dermatology DepartmentUniversidade Federal de São Paulo (UNIFESP), Escola Paulista de Medicina (EPM) Dermatology and Pathology DepartmentsUNIFESP, EPM, Dermatology DepartmentUNIFESP, EPM, Dermatology and Pathology DepartmentsSciEL
Recommended from our members
Future-proofing and maximizing the utility of metadata: The PHA4GE SARS-CoV-2 contextual data specification package.
BACKGROUND: The Public Health Alliance for Genomic Epidemiology (PHA4GE) (https://pha4ge.org) is a global coalition that is actively working to establish consensus standards, document and share best practices, improve the availability of critical bioinformatics tools and resources, and advocate for greater openness, interoperability, accessibility, and reproducibility in public health microbial bioinformatics. In the face of the current pandemic, PHA4GE has identified a need for a fit-for-purpose, open-source SARS-CoV-2 contextual data standard. RESULTS: As such, we have developed a SARS-CoV-2 contextual data specification package based on harmonizable, publicly available community standards. The specification can be implemented via a collection template, as well as an array of protocols and tools to support both the harmonization and submission of sequence data and contextual information to public biorepositories. CONCLUSIONS: Well-structured, rich contextual data add value, promote reuse, and enable aggregation and integration of disparate datasets. Adoption of the proposed standard and practices will better enable interoperability between datasets and systems, improve the consistency and utility of generated data, and ultimately facilitate novel insights and discoveries in SARS-CoV-2 and COVID-19. The package is now supported by the NCBI's BioSample database