Search results for "Research"
showing 10 items of 25967 documents
Could formaldehyde induce mutagenic and cytotoxic effects in buccal epithelial cells during anatomy classes?
2017
Background Due to increased formaldehyde exposure, carcinogenic to humans, several researches have been studying the potential toxicity and the safe levels for human beings. The aim of this study was to investigate mutagenicity and cytotoxicity in buccal epithelial exfoliated cells (BEC) of students subjected to formaldehyde (FA) during anatomy classes. Material and Methods BEC were collected periodically from 17 volunteers of undergraduate programs, who had participated in practical anatomy classes, before and after FA exposure. Cells were stained according to Feulgen method and then micronucleus test was applied. A total of 1,500 cells were assessed per individual in this study for the mi…
Patient-Derived Xenograft Models Reveal Intratumor Heterogeneity and Temporal Stability in Neuroblastoma.
2018
Patient-derived xenografts (PDX) and the Avatar, a single PDX mirroring an individual patient, are emerging tools in preclinical cancer research. However, the consequences of intratumor heterogeneity for PDX modeling of biomarkers, target identification, and treatment decisions remain under-explored. In this study, we undertook serial passaging and comprehensive molecular analysis of neuroblastoma orthotopic PDXs, which revealed strong intrinsic genetic, transcriptional, and phenotypic stability for more than 2 years. The PDXs showed preserved neuroblastoma-associated gene signatures that correlated with poor clinical outcome in a large cohort of patients with neuroblastoma. Furthermore, we…
Lamivudine/Adefovir Treatment Increases the Rate of Spontaneous Mutation of Hepatitis B Virus in Patients.
2016
The high levels of genetic diversity shown by hepatitis B virus (HBV) are commonly attributed to the low fidelity of its polymerase. However, the rate of spontaneous mutation of human HBV in vivo is currently unknown. Here, based on the evolutionary principle that the population frequency of lethal mutations equals the rate at which they are produced, we have estimated the mutation rate of HBV in vivo by scoring premature stop codons in 621 publicly available, full-length, molecular clone sequences derived from patients. This yielded an estimate of 8.7 × 10-5 spontaneous mutations per nucleotide per cell infection in untreated patients, which should be taken as an upper limit estimate becau…
Case-based surveillance of measles in Sicily during 2012-2017: The changing molecular epidemiology and implications for vaccine strategies.
2018
Following the indication of the World Health Organization, a national plan for the elimination of measles was approved in Italy and this included the improvement of the molecular surveil- lance of measles viruses and the interruption of indigenous transmission of the disease. Nevertheless, large outbreaks continue to occur in almost all regions of the country, includ- ing Sicily. Here we describe the epidemiology and molecular dynamics of measles viruses as a result of the measles surveillance activity carried out by the “Reference Laboratory for Measles and Rubella” in Sicily over a 5-year period. Biological samples of 259 suspected measles cases were tested for viral RNA detection and a t…
Field evaluation of a rapid antigen test (Panbio™ COVID-19 Ag Rapid Test Device) for COVID-19 diagnosis in primary healthcare centres.
2021
Abstract Objectives To our knowledge no previous study has assessed the performance of a rapid antigen diagnostic immunoassay (RAD) conducted at the point of care (POC). We evaluated the Panbio™ COVID-19 Ag Rapid Test Device for diagnosis of coronavirus 2019 disease (COVID-19) in symptomatic patients (n = 412) attending primary healthcare centres. Methods RAD was performed immediately after sampling following the manufacturer's instructions (reading at 15 min). RT-PCRs were carried out within 24 h of specimen collection. Samples displaying discordant results were processed for culture in Vero E6 cells. Presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in cell cultures…
miRNA92a targets KLF2 and the phosphatase PTEN signaling to promote human T follicular helper precursors in T1D islet autoimmunity.
2016
Aberrant immune activation mediated by T effector cell populations is pivotal in the onset of autoimmunity in type 1 diabetes (T1D). T follicular helper (TFH) cells are essential in the induction of high-affinity antibodies, and their precursor memory compartment circulates in the blood. The role of TFH precursors in the onset of islet autoimmunity and signaling pathways regulating their differentiation is incompletely understood. Here, we provide direct evidence that during onset of islet autoimmunity, the insulin-specific target T-cell population is enriched with a C-X-C chemokine receptor type 5 (CXCR5)(+)CD4(+) TFH precursor phenotype. During onset of islet autoimmunity, the frequency o…
Microenvironment in neuroblastoma: isolation and characterization of tumor-derived mesenchymal stromal cells
2018
Background It has been proposed that mesenchymal stromal cells (MSCs) promote tumor progression by interacting with tumor cells and other stroma cells in the complex network of the tumor microenvironment. We characterized MSCs isolated and expanded from tumor tissues of pediatric patients diagnosed with neuroblastomas (NB-MSCs) to define interactions with the tumor microenvironment. Methods Specimens were obtained from 7 pediatric patients diagnosed with neuroblastoma (NB). Morphology, immunophenotype, differentiation capacity, proliferative growth, expression of stemness and neural differentiation markers were evaluated. Moreover, the ability of cells to modulate the immune response, i.e. …
DNA methylation changes and somatic mutations as tumorigenic events in Lynch syndrome-associated adenomas retaining mismatch repair protein expression
2018
Background: DNA mismatch repair (MMR) defects are a major factor in colorectal tumorigenesis in Lynch syndrome (LS) and 15% of sporadic cases. Some adenomas from carriers of inherited MMR gene mutations have intact MMR protein expression implying other mechanisms accelerating tumorigenesis. We determined roles of DNA methylation changes and somatic mutations in cancer-associated genes as tumorigenic events in LS-associated colorectal adenomas with intact MMR. Methods: We investigated 122 archival colorectal specimens of normal mucosae, adenomas and carcinomas from 57 LS patients. MMR-deficient (MMR-D, n 49) and MMR-proficient (MMR-P, n 18) adenomas were of particular interest and were inter…
DRH1 - a novel blood-based HPV tumour marker.
2020
Abstract Background To date, no studies have successfully shown that a highly specific, blood-based tumour marker to detect clinically relevant HPV-induced disease could be used for screening, monitoring therapy response or early detection of recurrence. This study aims to assess the clinical performance of a newly developed HPV16-L1 DRH1 epitope-specific serological assay. Methods In a multi-centre study sera of 1486 patients (301 Head and Neck Squamous Cell Carcinoma (HNSCC) patients, 12 HIV+ anal cancer patients, 80 HIV-positive patients, 29 Gardasil-9-vaccinees, 1064 healthy controls) were tested for human HPV16-L1 DRH1 antibodies. Analytical specificity was determined using WHO referen…
Longitudinal Analysis of Serum Autoantibody-Reactivities in Patients with Primary Open Angle Glaucoma and Optic Disc Hemorrhage.
2015
Background The aim of our current investigation was to analyze the autoantibody-reactivities of primary open angle glaucoma patients with optic disc hemorrhage as possibly correlated to disease progression by means of a protein microarray approach. Methods Sera of patients with primary open angle glaucoma and optic disc hemorrhage (n = 16) were collected directly after study inclusion (0 weeks) and after 2 weeks, 4 weeks and 12 weeks. As a control group patients with primary open angle glaucoma (n = 18) were used (0 weeks and 12 weeks). Microarrays were incubated and occurring antibody-antigen-reactions were visualized with fluorescence labeled anti-human-IgG secondary antibodies. To detect…