109 research outputs found
A multicenter, prospective cohort study
Organ transplant recipients (OTRs) have a 100âfold increased risk of cutaneous
squamous cell carcinoma (cSCC). We prospectively evaluated the association
between β genus human papillomaviruses (βPV) and keratinocyte carcinoma in
OTRs. Two OTR cohorts without cSCC were assembled: cohort 1 was transplanted
in 2003â2006 (n = 274) and cohort 2 was transplanted in 1986â2002 (n = 352).
Participants were followed until death or cessation of followâup in 2016. βPV
infection was assessed in eyebrow hair by using polymerase chain
reactionâbased methods. βPV IgG seroresponses were determined with multiplex
serology. A competing risk model with delayed entry was used to estimate
cumulative incidence of histologically proven cSCC and the effect of βPV by
using a multivariable Cox regression model. Results are reported as adjusted
hazard ratios (HRs). OTRs with 5 or more different βPV types in eyebrow hair
had 1.7 times the risk of cSCC vs OTRs with 0 to 4 different types (HR 1.7,
95% confidence interval 1.1â2.6). A similar risk was seen with high βPV loads
(HR 1.8, 95% confidence interval 1.2â2.8). No significant associations were
seen between serum antibodies and cSCC or between βPV and basal cell
carcinoma. The diversity and load of βPV types in eyebrow hair are associated
with cSCC risk in OTRs, providing evidence that βPV is associated with cSCC
carcinogenesis and may present a target for future preventive strategies
\u3cem\u3eTrichodysplasia Spinulosa\u3c/em\u3e-Associated Polyomavirus Uses a Displaced Binding Site on VP1 to Engage Sialylated Glycolipids
Trichodysplasia spinulosa-associated Polyomavirus (TSPyV) was isolated from a patient suffering from trichodysplasia spinulosa, a skin disease that can appear in severely immunocompromised patients. While TSPyV is one of the five members of the polyomavirus family that are directly linked to a human disease, details about molecular recognition events, the viral entry pathway, and intracellular trafficking events during TSPyV infection remain unknown. Here we have used a structure-function approach to shed light on the first steps of TSPyV infection. We established by cell binding and pseudovirus infection studies that TSPyV interacts with sialic acids during attachment and/or entry. Subsequently, we solved high-resolution X-ray structures of the major capsid protein VP1 of TSPyV in complex with three different glycans, the branched GM1 glycan, and the linear trisaccharides Îą2,3- and Îą2,6-sialyllactose. The terminal sialic acid of all three glycans is engaged in a unique binding site on TSPyV VP1, which is positioned about 18 Ă
from established sialic acid binding sites of other polyomaviruses. Structure-based mutagenesis of sialic acid-binding residues leads to reduction in cell attachment and pseudovirus infection, demonstrating the physiological relevance of the TSPyV VP1-glycan interaction. Furthermore, treatments of cells with inhibitors of N-, O-linked glycosylation, and glycosphingolipid synthesis suggest that glycolipids play an important role during TSPyV infection. Our findings elucidate the first molecular recognition events of cellular infection with TSPyV and demonstrate that receptor recognition by polyomaviruses is highly variable not only in interactions with sialic acid itself, but also in the location of the binding site
The Role of Human Papillomaviruses and Polyomaviruses in BRAF-Inhibitor Induced Cutaneous Squamous Cell Carcinoma and Benign Squamoproliferative Lesions
Background: Human papillomavirus (HPV) has long been proposed as a cofactor in the pathogenesis of cutaneous squamous cell carcinoma (cSCC). More recently, the striking clinico-pathological features of cSCCs that complicate treatment of metastatic melanoma with inhibitors targeting BRAF mutations (BRAFi) has prompted speculation concerning a pathogenic role for oncogenic viruses. Here, we investigate HPV and human polyomaviruses (HPyV) and correlate with clinical, histologic, and genetic features in BRAFi-associated cSCC.
Materials and Methods: Patients receiving BRAFi treatment were recruited at Barts Health NHS Trust. HPV DNA was detected in microdissected frozen samples using reverse line probe technology and degenerate and nested PCR. HPV immunohistochemistry was performed in a subset of samples. Quantitative PCR was performed to determine the presence and viral load of HPyVs with affinity for the skin (HPyV6, HPyV7, HPyV9, MCPyV, and TSPyV). These data were correlated with previous genetic mutational analysis of H, K and NRAS, NOTCH1/2, TP53, CDKN2A, CARD11, CREBBP, TGFBR1/2. Chromosomal aberrations were profiled using single nucleotide polymorphism (SNP) arrays.
Results: Forty-five skin lesions from seven patients treated with single agent vemurafenib in 2012â2013 were analyzed: 12 cSCC, 19 viral warts (VW), 2 actinic keratosis (AK), 5 verrucous keratosis/other squamoproliferative (VK/SP) lesions, one melanocytic lesion and 6 normal skin samples. Significant histologic features of viral infection were seen in 10/12 (83%) cSCC. HPV DNA was detected in 18/19 (95%) VW/SP, 9/12 (75%) cSCC, 4/5 (80%) SP, and 3/6 (50%) normal skin samples and in 1/12 cases assessed by immunohistochemistry. HPyV was co-detected in 22/30 (73%) of samples, usually at low viral load, with MCPyV and HPyV7 the most common. SNP arrays confirmed low levels of chromosomal abnormality and there was no significant correlation between HPV or HPyV detection and individual gene mutations or overall mutational burden.
Conclusion: Despite supportive clinicopathologic evidence, the role for HPV and HPyV infection in the pathogenesis of BRAFi-induced squamoproliferative lesions remains uncertain. Synergistic oncogenic mechanisms are plausible although speculative. Nonetheless, with the prospect of a significant increase in the adjuvant use of these drugs, further research is justified and may provide insight into the pathogenesis of other BRAFi-associated malignancies
Trabalho infantil : uma anålise das tentativas de sua erradicação no Brasil
Orientadora: ProfÂŞ DrÂŞ Silvia Maria P. AraĂşjoDissertaçao (mestrado) - Universidade Federal do ParanĂĄ, Setor de Ciencias Humanas, Letras e Artes, Programa de PĂłs-Graduaçao em Sociologia. Defesa: Curitiba, 22/12/2003Inclui bibliografiaResumo: Esta dissertação pretende analisar a problemĂĄtica da erradicação do trabalho infantil a partir dos discursos que se produziram ao longo da histĂłria moderna, relativos Ă s descriçþes de infância e dos contextos que separam o mundo adulto do mundo infantil, ou, ao retrato da construção social do que representa a infância: o mundo do trabalho como retrato do universo adulto e a educação formal (escola) como sĂntese da vida em formação. Os pressupostos da educação formal e do trabalho norteiam as discussĂľes que embasam os discursos a partir dos quais, a reprodução de valores inerentes ao sistema capitalista e suas contradiçþes, evidenciam a necessidade de se elaborar um problema social, o qual necessita de descrição, avaliação e intervenção. Ao trazer a problemĂĄtica da construção do trabalho infantil como problema social, esta pesquisa pretende analisar o processo histĂłrico da construção da problemĂĄtica do trabalho infantil retratado como um problema que deve ser exterminado, segundo os discursos, tendo como base categorias trabalho e infância. Pretende ainda, compreender o contexto histĂłrico e socioeconĂ´mico no qual o trabalho infantil passou a ser combatido como um problema social, mais precisamente no Brasil, por meio de polĂticas pĂşblicas, bem como, identificar no processo do que se denomina de erradicação, a garantia do controle da formação de mĂŁo-de-obra, atravĂŠs dos programas voltados aos jovens e Ă s crianças pobres e vulnerĂĄveis. Por fim, esta pesquisa lança uma reflexĂŁo sobre a necessidade de participação das crianças na elaboração de documentos ou iniciativas, que garantam os direitos da infância e da adolescĂŞncia e que as mesmas possam escolher dentro de suas respectivas realidades, como traçar seus destinos. A pesquisa tem como base a coleta de dados documentais que evidenciam o pressuposto de trabalho infantil como um problema social, bem como, as contradiçþes no discurso da erradicação, contemplando documentos do PETI (Programa de Erradicação do Trabalho Infantil), do FĂłrum Nacional de Prevenção e Erradicação do Trabalho Infantil e do ECA (Estatuto da Criança e do Adolescente), alĂŠm de participaçþes nas reuniĂľes do FĂłrum, em Curitiba, na Procuradoria Regional do Trabalho, durante o ano de 2002
Communion by extension : discrepancies between policy and practice
The growing practice of Communion by Extension was given formal authorisation by the Church of England General Synod in 2000 with the expectation that it would be used in particular circumstances, including explicitly the rural multi-church benefice. This paper reviews the historical origins of the practice of Communion by Extension and clarifies the intentions of the authorisation given in 2000. Then the intentions of the 2000 authorisation are compared and contrasted with current parochial practice within one English diocese. Considerable divergence is found. Five main themes are identified and discussed: the relationship between worship and mission; the pressures on clerical time; sacramental self-sufficiency; the value given to familiarity; and the choice between reservation and congregationalism
Primary Polyomavirus Infection, Not Reactivation, as the Cause of Trichodysplasia Spinulosa in Immunocompromised Patients
Classic human polyomaviruses (JC and BK viruses) become pathogenic when reactivating from latency. For the rare skin disease trichodysplasia spinulosa, we show that manifestations of the causative polyomavirus (TSPyV) occur during primary infection of the immunosuppressed host. High TSPyV loads in blood and cerebrospinal fluid, sometimes coinciding with cerebral lesions and neuroendocrine symptoms, marked the acute phase of trichodysplasia spinulosa, whereas initiation and maturation of TSPyV seroresponses occurred in the convalescent phase. TSPyV genomes lacked the rearrangements typical for reactivating polyomaviruses. These findings demonstrate the clinical importance of primary infection with this rapidly expanding group of human viruses and explain the rarity of some novel polyomavirus-associated diseases.Peer reviewe
The respiratory virome and exacerbations in patients with chronic obstructive pulmonary disease
Introduction Exacerbations are major contributors to morbidity and mortality in patients with chronic obstructive pulmonary disease (COPD), and respiratory bacterial and viral infections are an important trigger. However, using conventional diagnostic techniques, a causative agent is not always found. Metagenomic next-generation sequencing (mNGS) allows analysis of the complete virome, but has not yet been applied in COPD exacerbations. Objectives To study the respiratory virome in nasopharyngeal samples during COPD exacerbations using mNGS. Study design 88 nasopharyngeal swabs from 63 patients from the Bergen COPD Exacerbation Study (2006-2010) were analysed by mNGS and in-house qPCR for respiratory viruses. Both DNA and RNA were sequenced simultaneously using an Illumina library preparation protocol with in-house adaptations. Results By mNGS, 24/88 samples tested positive. Sensitivity and specificity, as compared with PCR, were 96% and 98% for diagnostic targets (23/24 and 1093/1120, respectively). Additional viral pathogens detected by mNGS were herpes simplex virus type 1 and coronavirus OC43. A positive correlation was found between Cq value and mNGS viral normalized species reads (log value) (p = 0.002). Patients with viral pathogens had lower percentages of bacteriophages (p<0.001). No correlation was found between viral reads and clinical markers. Conclusions The mNGS protocol used was highly sensitive and specific for semi-quantitative detection of respiratory viruses. Excellent negative predictive value implicates the power of mNGS to exclude any pathogenic respiratory viral infectious cause in one test, with consequences for clinical decision making. Reduced abundance of bacteriophages in COPD patients with viral pathogens implicates skewing of the virome during infection, with potential consequences for the bacterial populations, during infection
Recommendations for the introduction of metagenomic high-throughput sequencing in clinical virology, part I:Wet lab procedure
Metagenomic high-throughput sequencing (mHTS) is a hypothesis-free, universal pathogen detection technique for determination of the DNA/RNA sequences in a variety of sample types and infectious syndromes. mHTS is still in its early stages of translating into clinical application. To support the development, implementation and standardization of mHTS procedures for virus diagnostics, the European Society for Clinical Virology (ESCV) Network on Next-Generation Sequencing (ENNGS) has been established. The aim of ENNGS is to bring together professionals involved in mHTS for viral diagnostics to share methodologies and experiences, and to develop application recommendations. This manuscript aims to provide practical recommendations for the wet lab procedures necessary for implementation of mHTS for virus diagnostics and to give recommendations for development and validation of laboratory methods, including mHTS quality assurance, control and quality assessment protocols
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Interpreting Cancer Genomes Using Systematic Host Perturbations by Tumour Virus Proteins
Genotypic differences greatly influence susceptibility and resistance to disease. Understanding genotype-phenotype relationships requires that phenotypes be viewed as manifestations of network properties, rather than simply as the result of individual genomic variations. Genome sequencing efforts have identified numerous germline mutations associated with cancer predisposition and large numbers of somatic genomic alterations. However, it remains challenging to distinguish between background, or âpassengerâ and causal, or âdriverâ cancer mutations in these datasets. Human viruses intrinsically depend on their host cell during the course of infection and can elicit pathological phenotypes similar to those arising from mutations. To test the hypothesis that genomic variations and tumour viruses may cause cancer via related mechanisms, we systematically examined host interactome and transcriptome network perturbations caused by DNA tumour virus proteins. The resulting integrated viral perturbation data reflects rewiring of the host cell networks, and highlights pathways that go awry in cancer, such as Notch signalling and apoptosis. We show that systematic analyses of host targets of viral proteins can identify cancer genes with a success rate on par with their identification through functional genomics and large-scale cataloguing of tumour mutations. Together, these complementary approaches result in increased specificity for cancer gene identification. Combining systems-level studies of pathogen-encoded gene products with genomic approaches will facilitate prioritization of cancer-causing driver genes so as to advance understanding of the genetic basis of human cancer
Discovery of a New Human Polyomavirus Associated with Trichodysplasia Spinulosa in an Immunocompromized Patient
The Polyomaviridae constitute a family of small DNA viruses infecting a variety of hosts. In humans, polyomaviruses can cause infections of the central nervous system, urinary tract, skin, and possibly the respiratory tract. Here we report the identification of a new human polyomavirus in plucked facial spines of a heart transplant patient with trichodysplasia spinulosa, a rare skin disease exclusively seen in immunocompromized patients. The trichodysplasia spinulosa-associated polyomavirus (TSV) genome was amplified through rolling-circle amplification and consists of a 5232-nucleotide circular DNA organized similarly to known polyomaviruses. Two putative âearlyâ (small and large T antigen) and three putative âlateâ (VP1, VP2, VP3) genes were identified. The TSV large T antigen contains several domains (e.g. J-domain) and motifs (e.g. HPDKGG, pRb family-binding, zinc finger) described for other polyomaviruses and potentially involved in cellular transformation. Phylogenetic analysis revealed a close relationship of TSV with the Bornean orangutan polyomavirus and, more distantly, the Merkel cell polyomavirus that is found integrated in Merkel cell carcinomas of the skin. The presence of TSV in the affected patient's skin was confirmed by newly designed quantitative TSV-specific PCR, indicative of a viral load of 105 copies per cell. After topical cidofovir treatment, the lesions largely resolved coinciding with a reduction in TSV load. PCR screening demonstrated a 4% prevalence of TSV in an unrelated group of immunosuppressed transplant recipients without apparent disease. In conclusion, a new human polyomavirus was discovered and identified as the possible cause of trichodysplasia spinulosa in immunocompromized patients. The presence of TSV also in clinically unaffected individuals suggests frequent virus transmission causing subclinical, probably latent infections. Further studies have to reveal the impact of TSV infection in relation to other populations and diseases
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