Publications by authors named "Alexandros Zafiropoulos"

The goal of this study is to test a novel device and methodology based on the "Pebble" platform and real-time quantitative colorimetric loop-mediated isothermal amplification (qcLAMP) during SARS-CoV-2 detection using crude samples and extracted RNA. The new method employs an inexpensive lightweight device aimed toward rapid point-of-care testing. An extensive evaluation was performed consisting of 1,693 clinical samples across five independent clinical testing centers.

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The circulation of certain SARS-CoV-2 variants may have a great impact on the epidemiological status of a geographical area; therefore, it is important that their presence is monitored. Currently, the gold standard method used to identify newly emerged variants is sequencing of either genes or whole genomes. However, since this method is relatively expensive and has a long turnaround time, other rapid strategies should also be employed.

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Background: Rapid and accurate diagnostics of patients with suspected seasonal influenza or pathogens of the upper respiratory tract is crucial. Fast detection is important especially for influenza A/B virus, so that isolation measures should be taken to prevent the spread of the virus.

Methods: We compared the performance of two syndromic testing methodologies (QIAstat-Dx RP, BioFire RP2plus) against the Alere™ i as the comparator method.

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The SARS-CoV-2 pandemic led to an urgent need for rapid diagnostic testing in order to inform timely patients' management. This study aimed to assess the performance of the STANDARD™ M10 SARS-CoV-2 assay as a diagnostic tool for COVID-19. A total of 400 nasopharyngeal or oropharyngeal swabs were tested against a reference real-time RT-PCR, including 200 positive samples spanning the full range of observed Ct values.

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Purpose: In the present study, we sought to investigate the presence of Parvovirus B19 in both abnormal and normal adjacent thyroid tissue specimens after total thyroidectomy as well as the extent that this phenomenon occurs in a population group referred to a tertiary surgical oncology department.

Methods: We detected Parvovirus B19 by Real-Time PCR in both abnormal and normal adjacent thyroid tissue specimens from 41 patients who underwent total thyroidectomy for thyroid disease (cancerous or benign). Hashimoto's thyroiditis, thyroid gland weight, maximum size of the predominant thyroid nodule as well as sex and age of the patients were also evaluated in respect to the Parvovirus B19 presence.

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The worldwide COVID-19 pandemic outburst has caused a serious public health issue with increasing needs of accurate and rapid diagnostic and screening testing. This situation requires an optimized management of the chemical reagents, the consumables, and the human resources, in order to respond accurately and effectively, controlling the spread of the disease. Testing on pooled samples maximizes the number of tested samples, by minimizing the time and the lab supplies needed.

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Intervertebral disc (IVD) degeneration has a complex multifactorial origin and it is tightly associated with changes in the secretion of proteoglycans and collagen of the Nucleus Pulposus (NP) extracellular matrix. Chronic infection by Herpes virus has been previously associated with disc degeneration after detection of Herpes Simplex Virus type-1 (HSV-1) and CMV DNA in human excised disc samples. The aim of the present study was to assess the effect of HSV-1 infection on proteoglycan synthesis employing human Nucleus Pulposus (HNPCs) cells as a model of intervertebral disc degeneration.

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Implantation failure is a major problem in human assisted reproduction, which persists regardless the optimization of endometrial receptivity and selection of genetically and morphologically healthy embryos. Since embryo-endometrium interaction depends on cell junctional, cell adhesion and cell-substratum adhesion molecules, the present study inquired whether in vitro growing murine embryos display similar to the in vivo growing embryos patterns of adhesion molecules. To this extend aVb3 expression and distribution in zygotes and 2-cell stage embryos were studied.

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Objective: To examine whether the levels of MCP-1, RANTES and MCP-3 in the peritoneal fluid correlate with endometriosis.

Study Design: Patients with endometriosis were compared with controls.

Setting: Department of Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine, New Haven, CT, USA.

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Background: The asymptomatic phase of HIV-1 infection is characterized by a progressive depletion of uninfected peripheral effector/memory CD4+ T cells that subsequently leads to immune dysfunction and AIDS symptoms. We have previously demonstrated that the presence of specific gp120/V3 peptides during antigen presentation can modify the activation of normal T-cells leading to altered immune function. The aim of the present study was to map the specific transcriptional profile invoked by an HIV-1/V3 epitope in uninfected T cells during antigen presentation.

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Paraoxonases and cytochromes P450 constitute two major classes of xenobiotic-metabolizing enzymes involved in the detoxification of pesticide chemicals. In this study, we examined the distribution of two common genetic polymorphisms of the paraoxonase 1 gene and one common polymorphism of the CYP1A1 gene, in relation to pathological diseases occurring in a rural population. Blood and hair samples were collected from 220 participants of an agricultural cohort in the south of Greece for genotype and pesticide analysis.

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Serum paraoxonase 1 (PON1) function has been associated with human cardiovascular disease. The projected mechanism postulates interaction of PON1 with lipoproteins and insulin signaling resulting in alterations in lipid homeostasis. Recently, PON2 was shown to directly regulate triglyceride accumulation in macrophages and PON1 was detected in the interstitial space of adipocytes.

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Estrogens are related with the growth and development of target tissues and play a critical role in breast cancer progression. The effects of estrogens are mediated by the estrogen receptors ERalpha and ERbeta, which are members of the nuclear steroid receptor superfamily. To date, it is not known how these hormones elicit many of their effects on extracellular matrix molecules and how these effects can be connected with ER expression.

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Fibrosarcoma is an uncommon soft tissue tumor with a complex cell microenvironment, particularly rich in glycosaminoglycans/proteoglycans (GAGs/PGs). Chondroitin sulfate proteoglycans (CSPGs) participate in the modulation of various cellular functions, including adhesion and migration. The role of chondroitin sulfate (CS) chains on adhesion, chemotaxis and migration of poorly differentiated fibrosarcoma B6FS cell was studied, utilizing exogenous CS treatment and chondroitinase digestions as well as specific modulators of CS synthesis.

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Decorin is a multifunctional molecule of the extracellular matrix. Among the multitude of assigned functions the most intriguing is the ability to inhibit the growth and the metastasis of a wide range of cancer cells in vitro. Decorin was established to directly interact with EGFR and erb2, inducing protracted receptor internalization, which results in attenuation of the receptor-mediated intacellular signaling and induction of apoptosis.

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Platelet derived growth factor (PDGF) is involved in the autocrine growth stimulation of normal and malignant cells, the stimulation of angiogenesis, and the recruitment and regulation of tumor fibroblasts. PDGF has been shown to physically interact with glycosaminoglycans which are abundant in the extracellular microenvironment. The present review discusses the effects of glycosaminoglycans on the functions mediated by the PDGF on cells of mesenchymal origin.

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Decorin is an established natural oncosuppressive factor whose action is being studied in detail. Recently, decorin gene therapy formulations using adenoviral vectors have been shown in several animal models with very promising results. The present study describes the first exception to the established oncosuppression model using human osteosarcoma cells.

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Osteosarcoma is the most common primary bone tumour associated with childhood and adolescence. The possible role of the small leucine-rich proteoglycan, lumican, in the growth and metastasis of various cancer types has recently been investigated. In this study, the expression of lumican was examined in moderately differentiated (MG-63) and well-differentiated (Saos 2) human osteosarcoma cell lines of high and low metastatic capability, respectively.

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Background: The chemokine receptor polymorphisms CCR5Delta32, CXCL12 3'A, CCR2-64I and CCR5-59029 G/A have been demonstrated to affect HIV-1 infection and progression.

Objective: We studied the impact of the above polymorphisms on the effectiveness of a 30-month treatment with highly active antiretroviral therapy (HAART) in 149 HIV-1 patients.

Study Design: We stratified the patients according to CD4 CDC criteria and applied Kaplan-Meier analysis using the following end-point criteria: (a) the time from HAART initiation to undetectable viral load (VL) counts (VL<50 copies/ml), (b) the duration of undetectable VL status and (c) the time required for CD4+ T-cell counts to pass over the 500 cells/ml threshold.

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Human carcinogenesis is a multistep process involving complicated genetic events in which several onco-genes and oncosuppressor genes are implicated. The role of ras oncogenes in cellular transformation and apoptosis has been extensively examined and the dual role of ras as oncogene and oncosuppressor gene has been supported. Activation of ras occurs either by genomic alterations such as point mutations or by modulation of Ras protein expression.

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Angiogenesis is a complex procedure induced by the secretion of numerous growth factors from endothelial cells. Vascular endothelial growth factor (VEGF), basic fibroblastic growth factor (FGF2), transforming growth factor-beta1, 2, 3 (TGFB1, 2, 3), and transforming growth factor-beta receptors (TGFBR1, 2, 3) mRNA expression pattern was evaluated in tissue samples with cervical intraepithelial neoplasia (CIN) and cervical cancer, compared to that of normal cervical tissues, and correlated to the clinical stage of the disease. Transcript levels of the above genes were assessed by RT-PCR analysis in a total of 44 cervical specimens.

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It is well documented that inflammation plays a major role in the establishment and progression of atherosclerosis. Endothelial cells, vascular smooth muscle cells and monocytes/macrophages are involved in this process by expressing inflammatory factors. The aim of the present study was to evaluate potential association and risk of VEGF-A and TGF-beta1 in human coronary atherosclerotic lesions.

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ND10 structures are disrupted during herpes simplex virus type 1 (HSV-1) infection by viral regulatory protein ICP0. The significance of this effect remains controversial, partly because of a report that high-level expression of the major ND10 promyelocytic leukemia (PML) protein precludes ND10 disruption yet does not inhibit HSV-1 infection. Here we demonstrate dramatic reorganization of ND10 during HSV-1 infection by live-cell microscopy, even in the presence of overexpressed PML.

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Objective: Overexpression of p21 protein has been detected in human cervical cancer. However, to date, there are no data on the differential activation of the three ras genes at the transcriptional level in cervical lesions. The purpose of this study was to evaluate the quantitative and qualitative changes of expression of the ras family genes in the development of human cervical cancer.

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BACKGROUND: Macrophages can produce vascular endothelial growth factor (VEGF) in response to hypoxia, transforming growth factor beta1 (TGF-beta1), angiotensin II, basic fibroblast growth factor (bFGF), and interleukin-1. These factors have been found in the serum of coronary artery disease (CAD) patients as well as in atherosclerotic lesions. The aim of the present study was to test the hypothesis that the expression of VEGF, TGF-beta1 and bFGF in peripheral monocytes and lymphocytes is related to CAD.

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